Abstract:
A new method for the identification of useful promoters is disclosed. The method is capable of identifying bacterial promoters sensitive to a particular cellular insult and may be modified to identify promoters sensitive to herbicides and crop protection chemicals. Constructs comprising promoters upstream of a luminescent reporter genes are placed in transformed hosts. Transformants grown in liquid media to a predetermined growth stage and contacted with a cellular insult are assessed for regulatory region activity by measurement of the resulting change in bioluminescence. The method is able to identify promoters undetectable by standard methods.

Description:
This is a division of application Ser. No. 08/735,545 field Oct. 23, 1996, now U.S. Pat. No. 6,025,131. 
    
    
     FIELD OF INVENTION 
     The invention relates to the discovery and characterization of regulated promoters aided by use of reporter gene fusions. More specifically the invention creates gene fusion comprising bioluminescent reporter genes in transformed hosts grown in liquid media to identify regulated promoters. 
     BACKGROUND OF THE INVENTION 
     Technological advances within the chemical arts supporting the agrochemical, pharmaceutical and environmental industries have made possible the synthesis of vast arrays of chemical compounds. The utility of these compounds is modeled on various structure-function relationships. Compound utility of often confirmed through screening methods designed to associate these compounds with desired known activities. Currently, methods of synthesis are capable of producing far more compounds than can be reasonably screened. A need exists for the development of rapid high-throughput screens that are able to analyze vast numbers of compounds for putative agrochemical, environmental, or pharmaceutical activities. 
     Current screening methods are often costly, time intensive, and lacking in specificity where the screens must rely on studies in whole plants and animals. A variety of methods have been developed using engineered microorganisms to detect and characterize compound activity. One such test is the Ames test (McCann et al.  Mutat. Res.  (1984), 134(1), 1-47) where Salmonella sp. are used to characterize compounds as mutagenic or pro-mutagenic. The Ames test relies on the unique enzymatic properties of  S. typhimurium  to characterize xenobiotics as mutagens or pro-mutagens. Other microorganism-based systems for the characterization of compounds have relied on the specificity of gene promoters or regulatory regions to identify potential compound activity. For example, Orser et al. ( In Vitro Toxicol.  (1995), 8(1):71-85) utilizes a stress promoter fused to a promoterless lacZ structural gene to screen compounds for environmental toxicity, Molders et al. (WO 9008836) teaches the use of recombinant bacteria to detect the presence of mercury using a gene complex consisting of a mer regulatory region that is hypersensitive to induction by mercury and Burlage et al. ( J. Bacteriol,  172 (9):4749-4757 (1990)) recites a method using a naphthalene sensitive regulatory region from plasmid NAH7 to detect naphthalene-like compounds. 
     Microbiological methods such as these hold great promise for the screening of compounds for specific activities; however they are impeded by the lack of a facile reporting system and by the difficulty in identifying regulatory regions specific for the activities to be screened for. A rapid method for the identification of new, compound sensitive regulatory regions combined with a facile reporting gene would represent a significance advance in the art of compound screens. Genes responsible for bacterial bioluminescence are gaining increasing interest as facile reporters and offer a partial solution to the development of rapid high-throughput screens for new compound activities. 
     Bioluminescent bacteria are found in marine and terrestrial environments. The lux gene products from marine organisms often exhibit thermolability such that they do not function well at typical growth temperatures for other bacteria (Szittner and Meighen,  J. Biol. Chem.,  265:16581-16587 (1990); Rupani et al.,  Biotechnol Prog,  12:387-392 (1996); Hill et al.,  Biotechnol Appl Biochem,  17:3-14 (1993)). In contrast, the lux gene products from the terrestrial microorganism  Photorhabdus luminescens  (formerly called  Xenorhabdus luminescens ) are stable at temperatures up to 45° C. (Szittner and Meighen,  J. Biol. Chem.,  265:16581-16587 (1990)). Therefore, the advantage of the thermostable lux genes is that a larger range of assay temperatures are available for use. 
     Recent advances in recombinant DNA technology have made it possible to express the luciferase (lux) gene complex as heterologous gene products. This is generally accomplished by placing the lux structural gene complex under the control of a host promoter. So, for example, cDNA encoding firefly luciferase has been expressed in  E. coli  under the control of the lacZ promoter. (Tatsumi et al.,  Biochem. Biophys Acta.,  1131, 2:161-165, (1992)), and the luxAB fusion gene has been expressed in Bacillus at levels comparable to those achievable in  E. coli  by placing it under the control of the powerful Pxyn promoter (Jacobs et al.,  Mol. Gen. Genet.,  230(1-2):251-256, (1991)). 
     Stress genes are found in all cells and are defined as those genes activated as a result of any type of insults that might alter the normal cellular metabolism. Environmental insults often induce synthesis of an overlapping set of proteins. The most well recognized class of stress genes are the heat shock genes encoding a set of cellular proteins thought to have roles in refolding, recycling and resynthesis of proteins. The heat shock phenomenon was first described as a response to an increased temperature. Subsequent work has shown that exposure to a variety of insults including phage infection, macrophage envelopment, as well as the presence of organic molecules and heavy metals can also trigger the heat shock response. The common theme of the inducing agents may be unfolding of some proteins within the cell. (LaRossa et al.,  Mol. Micriobiol.,  5(3):529-523, (1991)). Thus the response may integrate and report a wide range of environmental insults. VanBogelen et al., ( J. Bacteriol.,  169(1):26-32, (1987)) have demonstrated that a variety of chemicals are able to induce the heat shock genes in  E. coli , including CdCl 2 , H 2 O 2 , ethanol, puromycin and nalidixic acid. Blom et al., ( Appl. Environ. Microbiol.,  58(1):331-334, (1992)) teach that the exposure of  E. coli  cultures to benzene, CdCl 2 , chlorpyrivos, 2,4-dichloraniline, dioctylphtalate, hexachlorobenzene, pentachlorophenol, trichlorethylene, and tetrapropylbenzosulfonate leads to the induction of up to 39 different stress proteins, as analyzed by two dimensional gel electrophoresis. LaRossa et al. (PCT International Application WO 94/13831) have transformed  E. coli  with a construct comprised of luxCDABE operably linked to a variety of stress promoters. They have used the microorganisms to detect a variety of environmental insults such as ethanol, CdCl 2 , and toluene. The presence of a sublethal concentration of the insult is indicated by an increase in bioluminescence. The detector organism described in WO 94/13831 was also used in a lyophilized form to detect similar environmental stresses by an increase in bioluminescence (Van Dyk, T. and Wagner, W., International Application No. PCT/US 95/15224. 
     Since the cell attempts to maintain a steady state, stress responses are activated well below the minimal inhibitory concentration for any condition that serves as a triggering factor. It would be useful to identify complete sets of promoters induced by any particular stress. 
     Thus, genes responsible for bacterial bioluminescence offer a partial solution to the need for a microorganism-based screening method for compound activity. Still needed, however, is a rapid method for the identification of useful regulatory regions. 
     Various methods of screening for bacterial promoter activity and for regulatory regions affected by various conditions are known. It is very common to use reporter genes for such a task. For example, transposons which can be inserted throughout the genome can be engineered to have reporter genes that require an external promoter sequence to be expressed and hence activity of the reporter gene is indicative of transcription initiated at the upstream chromosomal promoter sequences. A classic example of this approach is the work of Kenyon and Walker in discovering genes induced by DNA damage (Kenyon and Walker,  Proc. Natl. Acad. Sci. U.S.A.,  77:2819-2823 (1980)). Many such transposons are available and have been recently reviewed (Berg and Berg,  Transposable element tools for microbial genetics, in Escherichia coli and Salmonella Cellular and Molecular Biology , p.2588-2612, F. C. Neidhardt, Editor. 1996, ASM Press: Washington, D.C.). Alternatively, plasmids with reporter genes lacking promoter activity have also been used to discover promoters, such as the vectors described by Simons et al.,  Gene,  53:85-96 (1987)). These plasmids have a multiple cloning site (MCS) upstream of the lacZYA operon that lacks its normal promoter. Just upstream of the MCS were placed multiple transcription terminators so that transcription initiated at other places on the plasmid would terminate prior to the lacZ reporter gene. 
     One of the reporters of transcriptional activity frequency used in transposons and plasmids are the bacterial lux genes (Engebrecht et al.,  Science,  227:1345-1347 (1985)). The lux reporter is distinct because the reporter gene products&#39; activity, light production, can be measured without disruptin the cell. Furthermore, if the five gene luxCDABE reporter system is used, continuous monitoring of light production is possible without adding substrate exogenously. However, previous use of lux reporters for discovery of promoters have not taken advantage of such continuous monitoring and have, in general, qualitatively estimated promoter activity by the light production on petri plates (Carmi, O. A., et al.,  J. Bacteriol.,  169:2165-2170 (1987); Guzzo and DuBow,  Arch. Microbial.,  156:444-448 (1991); Guzzo et al.,  Appl. Environ. Microbiol.,  57:2255-2259 (1991); Guzzo and DuBow,  Mol. Gen. Genet.,  242:455-460 (1994); Kragelund et al.,  FEMS Microbiol. Ecol.,  17:95-106 (1995); Waterfield et al.,  Gene,  165:9-15 (1995)). 
     These previously used methods of screening for lux reporter activity on petri plates have been limited by being restricted to growth conditions and averaged stages of growth of bacterial cells within colonies on solidified medium. It was also not possibly to apply a stress condition and quickly visualize changes in gene expression. 
     The problem to be overcome, therefore is a method for the identification of gene regulatory regions, responsive to a particular cellular stress, such as that produced by herbicides or crop protection chemicals. Applicants have solved the stated problem by randomly fusing regulatory regions to a bacterial luminescent gene complex where contacting the fusion in a suitable host with a cellular insult producing a cellular stress results in detection of that cellular stress by an increase in cellular luminescence. Applicants methods of screening in liquid medium has the additional advantage of being able to detect regulatory regions that cannot be discovered by current methods, which are restricted to screening on the basis of colony formation on solid medium. The versatility of being able to screen for stress or chemical responsive regulatory regions rapidly and in a growth phase of the investigators choice represents a clear advance in the art. 
     SUMMARY OF THE INVENTION 
     Applicants have provided a method for identifying regulatory regions modulated by a cellular insult in a specific gene pool having the steps: 
     (i) creating a library of gene fusions to a luminescent reporter gene complex in suitable bacteria to create fusion-containing strains; 
     (ii) culturing individual gene fusion-containing strains in liquid media; 
     (iii) contacting the fusion-containing strains at a particular growth phase with a cellular insult for which the fusion-containing strain is known to be sensitive; and 
     (iv) analyzing the fusion-containing strain for a change in luminescence relative to a baseline luminescence, said change in luminescence indicating that the regulatory region is modulated by the cellular insult. 
     In particular, the method permits recovering the fusion-containing strains containing a regulatory region modulated by the cellular insult. 
     The method uses a luminescent reporter gene complex selected from the group consisting of a bacterial lux gene complex, a gene complex encoding luciferase from Renella species, and a luc gene complex, and more particularly, a thermostable lux gene complex or a lux CDABE gene complex. 
     The method can be used with any cellular insult, more particularly, with a crop protection chemical such as sulfometuron methyl (SM), one member of the class of N-(heterocyclicaminocarbonyl)sulfonamide-containing herbicidal chemical compounds. 
     Particular embodiments of the invention include 1) an  E. coli  1.9 kb genomic segment containing an SM-responsive regulatory region, said genomic segment bounded by SEQ ID NO: 1 and SEQ ID NO: 2; 2) an  E. coli  1.4 kb genomic segment containing an SM-responsive regulatory region, said genomic segment bounded by SEQ ID NO: 15 and SEQ ID NO: 16; 3) an  E. coli  1.8 kb genomic segment containing an SM-responsive regulatory region, said genomic segment bounded by SEQ ID NO: 11 and SEQ ID NO: 12; and 4) an  E. coli  1.6 kb genomic segment containing an SM-responsive regulatory region, said genomic segment bounded by SEQ ID NO: 19 and SEQ ID NO: 20. 
     The invention also encompasses plasmids containing: 
     (i) an  E. coli  genomic segment containing an SM-responsive regulatory region operably linked to a thermostable luxCDABE gene complex; and 
     (ii) a transcription terminator region upstream of said promoter. 
     The particular plasmids have an  E. coli  genomic segment bounded by unique pairs of DNA fragments selected from the group consisting of SEQ ID NOS: 1 and 2, SEQ ID NOS: 3 and 4, SEQ ID NOS: 5 and 6, SEQ ID NOS: 7 and 8, SEQ ID NOS: 9 and 10, SEQ ID NOS: 11 and 12, SEQ ID NOS: 13 and 14, SEQ ID NOS: 15 and 16, SEQ ID NOS: 17 and 18, SEQ ID NOS: 19 and 20, SEQ ID NOS: 21 and 22, SEQ ID NOS: 23 and 24, and SEQ ID NOS: 25 and 26. 
     The invention also encompasses transformants comprising a suitable host cell and the disclosed plasmid wherein the transformant is sensitive to SM. 
     The suitable host cell used in the transformant is a bacteria classified in the Family Enterobacteriaceae, and particularly preferred is  Escherichia coli.    
     A further embodiment of the invention is a method to detect chemical compounds potentially useful as a crop protection chemical having the steps: 
     (i) contacting the chemical compound with a detector organism containing a genomic segment comprising a responsive regulatory region operably linked to a luminescent reporter gene complex; 
     (ii) measuring an increase in bioluminescence in the detector organism, the increase in bioluminescent indicating that the chemical compound is potentially useful as a crop protection chemical. 
     The genomic segments useful in the invention are selected from the group consisting of a) an  E. coli  1.9 kb genomic segment containing an SM-responsive regulatory region, said segment bounded by SEQ ID NO: 1 and SEQ ID NO: 2; b) an  E. coli  1.4 kb genomic segment containing an SM-responsive regulatory region, said segment bounded by SEQ ID NO: 3 and SEQ ID NO: 4; c) an  E. coli  1.9 kb genomic segment containing an SM-responsive regulatory region, said segment bounded by SEQ ID NO: 5 and SEQ ID NO: 6; d) an  E. coli  1.3 kb genomic segment containing an SM-responsive regulatory region, said segment bounded by SEQ ID NO: 7 and SEQ ID NO: 8; e) an  E. coli  2.5 kb genomic segment containing an SM-responsive regulatory region, said segment bounded by SEQ ID NO: 9 and SEQ ID NO: 10; f) an  E. coli  1.8 kb genomic segment containing an SM-responsive regulatory region, said segment bounded by SEQ ID NO: 11 and SEQ ID NO: 12; g) an  E. coli  1.2 kb genomic segment containing an SM-responsive regulatory region, said segment bounded by SEQ ID NO: 13 and SEQ ID NO: 14; h) an  E. coli  1.4 kb genomic segment containing an SM-responsive regulatory region, said segment bounded by SEQ ID NO: 15 and SEQ ID NO: 16; i) an  E. coli  1.3 kb genomic segment containing an SM-responsive regulatory region, said segment bounded by SEQ ID NO: 17 and SEQ ID NO: 18; j) an  E. coli  1.6 kb genomic segment containing an SM-responsive regulatory region, said segment bounded by SEQ ID NO: 19 and SEQ ID NO: 20; k) an  E. coli  1.9 kb genomic segment containing an SM-responsive regulatory region, said segment bounded by SEQ ID NO: 21 and SEQ ID NO: 22; l) an  E. coli  1.0 kb genomic segment containing an SM-responsive regulatory region, said segment bounded by SEQ ID NO: 23 and SEQ ID NO: 24; and m) an  E. coli  2.0 kb genomic segment containing an SM-responsive regulatory region, said segment bounded by SEQ ID NO: 25 and SEQ ID NO: 26. 
     Gene fusions useful in the invention include those a) comprising the SM-responsive regulatory region contained within the  E. coli  1.9 kb genomic segment of claim  13 , the SM-responsive regulatory region operably linked to a luminescent reporter gene complex; b) comprising the SM responsive regulatory region contained within the genomic segment bounded by SEQ ID NO: 3 and SEQ ID NO: 4, the regulatory region operably linked to a luminescent reporter gene complex; c) comprising the SM-responsive regulatory region contained within the genomic segment bounded by SEQ ID NO: 5 and SEQ ID NO: 6, the regulatory region operably linked to a luminescent reporter gene complex; d) comprising the SM-responsive regulatory region contained within the genomic segment bounded by SEQ ID NO: 7 and SEQ ID NO: 8, said regulatory region operably linked to a luminescent reporter gene complex; e) comprising the SM responsive regulatory region contains within the genomic segment bounded by SEQ ID NO: 9 and SEQ ID NO: 10, the regulatory region operably linked to a luminescent reporter gene complex; f) comprising the SM-responsive regulatory region contained within the  E. coli  1.8 kb genomic segment of claim  15 , the regulatory region operably linked to a luminescent reporter gene complex; g) comprising the SM-responsive regulatory region contained within the genomic segment bounded by SEQ ID NO: 13 and SEQ ID NO: 14, said regulatory region operably linked to a luminescent reporter gene complex; h) comprising the SM-responsive regulatory region contained within the  E. coli  1.4 kb genomic segment of claim  14 , the regulatory region operably linked to a luminescent reporter gene complex; i) comprising the SM-responsive regulatory region contained within the genomic segment bounded by SEQ ID NO: 17 and SEQ ID NO: 18, the regulatory region operably linked to a luminescent reporter gene complex; j) comprising the SM-responsive regulatory region contained within the  E. coli  1.7 kb genomic segment of claim  16 , the regulation region operably linked to a luminescent reporter gene complex; k) comprising the SM-responsive regulatory region contained within the genomic segment bounded by SEQ ID NO: 21 and SEQ ID NO: 22the regulatory region operably linked to a luminescent reporter gene complex; l) comprising the SM-responsive regulatory region contained within the genomic segment bounded by SEQ ID NO: 23 and SEQ ID NO: 24, the regulatory region operably linked to a luminescent reporter gene complex; and m) comprising the SM-responsive regulatory region contained within the genomic segment bounded by SEQ ID NO: 25 and SEQ ID NO: 26, the regulatory region operably linked to a luminescent reporter gene complex. 
    
    
     BRIEF DESCRIPTION OF DRAWINGS, BIOLOGICAL DEPOSITS, AND SEQUENCE LISTING 
     The file of this patent contains at least one drawing executed in color. Copies of this patent with color drawing will be provided by the Patent and Trademark Office upon request and payment of the necessary fee. 
     FIG. 1 shows the restriction sites and genes of plasmid pDEW201, a promoter probe vector. 
     FIGS. 2 and 3 show graphically light production as a function of insert size for individual transformants of Library A and Library B, respectively. 
     FIG. 4 shows graphically the induction of bioluminescence of transformant DPD2088 by sulfometuron methyl. 
     FIG. 5 shows graphically patterns of bioluminescence induction in transformants DPD3509, DPD2087, and DPD2081 by various herbicidal compounds. 
     FIG. 6 is a color-enhanced, electronic image of an X-ray film comparing bioluminescence of transformants DPD2084, DPD2081, DPD2088, DPD3512, and DPD2092 that were cultured on plates with and without sulfometuron methyl induction. 
    
    
     Applicants have made the following biological deposits under the terms of the Budapest Treaty of the International Recognition of the Deposit of Microorganisms for the Purposes of Patent Procedure: 
     
       
         
               
               
               
             
           
               
                   
               
               
                 Depositor Identification 
                 Int‘l. Depository 
                   
               
               
                 Reference 
                 Designation 
                 Date of Deposit 
               
               
                   
               
             
             
               
                   Escherichia coli  DPD2083 
                 ATCC 98227 
                 Oct. 16, 1996 
               
               
                 (host strain DPD1675 
               
               
                 containing plasmid PDEW201) 
               
               
                   
               
             
          
         
       
     
     “ATCC” refers to the American Type Culture Collection international depository located at 6801 University Blvd., Manassas, Va. 20110-2209, U.S.A. The designations refer to the accession number of the deposited material. 
     Applicants have provided 28 sequences in conformity with Rules for the Standard Representation of Nucleotide and Amino Acid Sequences in Patent Applications (Annexes I and II to the Decision of the President of the EPO, published in Supplement No. 2 to OJ EPO, 12/1992), and with 37 C.F.R. 1.821-1.825 and Appendices A and B (Requirements for Application Disclosures Containing Nucleotides and/or Amino Acid Sequences). 
     DETAILED DESCRIPTION OF THE INVENTION 
     Applicants have solved the significant problem of how to identify regulatory regions affected by cellular stress such as that created to crop protection chemicals in cells growing in a specified growth phase in a liquid medium. The solution involves analyzing luminescence and changes in luminescence following stress of cells grown to a specified growth phase in liquid medium. Using this method, promoters encompassing &gt;1000-fold range of activity were readily found, which is far greater than the range of promoter activities found by previously used methods. For example, Waterfield et al (Waterfield, et al.,  Gene,  165:9-15 (1995)) using standard colony formation methods found promoters in  Lactococcus lactis  encompassing only a 71-fold range of activity. Furthermore, several genetic fusions to previously uncharacterized or known genes of  E. coli  were found by this method. Thus the instant method is able to detect promoters or stress responsive regulatory regions undetectable by current methods. 
     Utility Statement 
     The present invention provides a method of discovery and characterization of promoter regions using probe vectors that use a bioluminescent reporter gene complex. Isolated chromosomal DNA is digested with a restriction enzyme to give overlapping fragments, which are subsequently ligated upstream of the reporter genes. Those DNA sequences containing promoters will result in transcription and subsequent translation of the reporter gene products and hence light production from cells containing the fusion plasmid. Quantitation of this bioluminescence results in identification of sequences with promoter activity. 
     The following definitions are used herein and should be referred to for claim interpretation. 
     The term “bioluminescence” refers to the phenomenon of light emission from any living organism. 
     The term “baseline bioluminescence” refers to light emission of a microorganism in the absence of stress. 
     The term “lux” refers to the lux structural gene which include luxA, luxB, luxC, luxD and luxE and which are responsible for the phenomenon of bacterial bioluminescence. A lux gene complex might include all of the independent lux genes, acting in concert, or any subset of the lux structural genes so long as luxA and luxB are part of the complex. 
     The term “stress” or “cellular stres” refers to the condition produced in a cell as the result of exposure to a cellular insult. A “cellular insult” may be any substance or change in the cellular environment that results in an alteration of normal cellular metabolism in a bacterial cell or population of cells. Such cellular insults may include, but are not limited to, chemicals (such as herbicides, crop protection chemicals, environmental pollutants, heavy metals), physical treatments such as changes in temperature, changes in pH, agents producing oxidative damage or DNA damage (such as from UV exposure), anaerobiosis, biological insults such as the introduction of other life forms (viruses, bacteria, etc.) into the bacterial culture, or changes in nutrient availability. 
     A “luminescent reporter gene complex” means any reporter gene or genes the products of which result in light production, such as the bacterial lux genes, the firefly (for example,  Photinus pyralis ), or click beetle (for example,  Pyrophorus plagiophthalamus ) luciferase genes (luc), or the gene encoding the luciferase for the sea pansy,  Renilla reniformis.    
     “Host cell sensitivity” is a characteristic of a bacterial strain such that its metabolic activity is inhibited by addition of a chemical compound, biological entity, or physical treatment. 
     The term “multiple cloning site” (MCS) refers to a genetic element in which multiple sites of restriction endonuclease cleavage are embedded. 
     The terms “promoter” and “promoter region” refer to a sequence of DNA, usually upstream of (5′ to) the protein coding sequence of a structural gene, which controls the expression of the coding region by providing the recognition for RNA polymerase and/or other factors required for transcription to start at the correct site. Promoter sequences are necessary but not always sufficient to drive the expression of the gene. In this method, promoters are defined by their ability to result in expression of the reporter gene complex when cloned upstream of the reporter genes. Furthermore, activation of the promoter by a stress is defined as an increase of activity of the reporter gene complex following application of the stress. 
     A “fragment” constitutes a fraction of the DNA sequence of the particular region. 
     “Gene fusion” is a hybrid DNA fragment comprising a regulatory signal essential for transcription (referred to as a promoter) fused to at least one structural gene sequence coding for a specific polypeptide. 
     The term “genomic segment” refers to a DNA fragment containing a gene regulatory region. Genomic segments of the present invention are typically derived from the  E. coli  genome and contain regulatory regions responsive to a variety of cellular insults including those produced by contact with crop protection chemicals and herbicides. 
     The term “regulatory region” refers to a DNA fragment containing any of the genetic elements responsible for directing gene transcription and translation, including promoter or initiation control regions, coding regions, open reading frames (ORF) and transcriptional termination regions. Regulatory regions may be positively activated by a variety of stimuli resulting in up-regulation of genes and an increase in transcription. “Regulation” and “regulate” refer to the modulation of gene expression controlled by DNA sequence elements located primarily, but not exclusively upstream of (5′ to) the transcription start of a gene. Regulation may result in an all-or-none response to a stimulation, or it may result in variations in the level of gene expression. In the context of the present invention, regulatory regions activated by or responsive to sulfometuron methyl (“SM-responsive”) were identified. For a review of regulation of bacterial genes see  Escherichia coli and Salmonella Cellular and Molecular Biology , (1225-1309), F. C. Neidhardt, Editor. 1996, ASM Press: Washington, D.C.). 
     The term “coding sequence” refers to that portion of a gene encoding a protein, polypeptide, or a portion thereof, and usually excluding the regulatory sequences which drive the initiation of transcription. A coding sequence may be one normally found in the cell or it may be one not normally found in a cellular location, but one that is instead introduced, in which case it is termed a heterologous gene. The coding sequence may be a composite of fragments derived from different sources, naturally occurring or synthetic. 
     The term “operably linked” refers to the fusion of two fragments of DNA in a proper orientation to be transcribed into functional RNA. 
     The term “expression” refers to the transcription and translation to gene product from a gene coding for the sequence of the gene product. In the expression, a DNA chain coding for the sequence of gene product is first transcribed to a complimentary RNA which is often a messenger RNA and, then, the thus transcribed messenger RNA is translated into the above-mentioned gene product if the gene product is a protein. 
     The term “plasmid” or “vector” as used herein refers to an extra chromosomal element often carrying genes which are not part of the central metabolism of the cell, and usually in the form of circular double-stranded DNA molecules. Such elements may be autonomously replicating sequences, genome integrating sequences, phage or nucleotide sequences, linear or circular, of a single- or double-stranded DNA or RNA, derived from any source, in which a number of nucleotide sequences have been joined or recombined into a unique construction which is capable of introducing a promoter fragment and DNA sequence for a selected gene product along with appropriate 3′ untranslated sequence into a cell. Plasmid pDEW201 has the unique features of carrying the  Photorhabdus luminescens  luxCDABE genes without a promoter, upstream of which are transcription terminator sequences and a MCS. The derivatives of pDEW201 described herein contain  E. coli  chromosomal DNA cloned into the MCS. 
     The term “restriction endonuclease” or “restriction enzyme” refers to an enzyme which binds and cuts within a specific nucleotide sequence within double-stranded DNA. 
     “Liquid media” refers to microbial growth medium that is not solidified, such as by addition of agar. 
     “Growth phase” refers to stages of bacterial cell growth of the cells in liquid medium which allows for a uniform population of cells to be produced. Examples of growth phases include such as early log phase, mid log phase, late log phase or stationary phase. 
     The term “log phase” or “log phase growth” refers to cell cultures of detector organisms growing under conditions permitting the exponential multiplication of the detector cell number. 
     The term “Relative Light Unit” is abbreviated “RLU” and refers to a measure of light emission as measured by a luminometer, calibrated against an internal standard unique to the luminometer being used. 
     The term “crop protection chemical” or “CPC” refers to compounds having toxic or repellent effect on insects, plant pathogens, or crop-completing plant species known to damage crop plants. CPC includes pesticides (paraquat, copper sulfate, metidathion), anti-pathogenic compounds such as fungicides (chlorothalonil) or responsible for insect behavior modulation (pheromones, allomones and kairomones), and herbicides referring to compounds having specific or general toxicity to plant species. Typical herbicides include but are not limited to the class of sulfonylurea herbicides and sulfonanilide herbicides (chlorsulfuron, triasulfuron, metsulfuron-methyl), auxin herbicides (e.g. dicamba, 2-methyl-4-chlorophenoxyacetic acid, picloram, quinclorac, quinmerac), pre-emergence herbicideds (metribuzin), and post-emergence herbicides (Clethodim Pendimethalin, oryzalin, dithiopyr, oxadiazon, prodiamine, 2-4-D). 
     “Sulfonylurea herbicides” are defined as N-(heterocyclicaminocarbonyl)-arylsulfonamide-containing herbicidal compounds that inhibit the enzyme acetolactate synthase, such as sulfometuron methyl. 
     The term “sulfometuron methyl” refers to 2-[[[[(4,6-dimethyl-2-pyrimidinyl)amino]carbonyl]amino]sulfonyl]benzoic acid, methyl ester (CAS registry number 74222-97-2), and is abbreviated as “SM”. 
     The term “sulfometuron methyl inducible promoter” is a promoter that is activated by the presence of sulfometuron methyl. 
     The term “detector organism” refers to an organism which contains a gene fusion consisting of a promoter fused to a structural gene and which is capable of expressing the lux gene products in response to cellular stress. Typical detector organisms include but are not limited to bacteria. 
     “Enteric bacteria” are members of the family Enterobacteriaceae, and include such members as Escherichia, Salmonella, and Shigella. They are gram-negative straight rods, 0.3-1.0×1.0-6.0 μm, motile by peritrichous flagella, except for Tatumella, or nonmotile. They grow in the presence and absence of oxygen and grow well on peptone, meat extract, and (usually) MacConkey&#39;s media. Some grown on D-glucose as the sole source of carbon, whereas others require vitamins and/or mineral(s). They are chemoorganotrophic with respiratory and fermentative metabolism but are not halophilic. Acid and often visible gas is produced during fermentation of D-glucose, other carbohydrates, and polyhydroxyl alcohols. They are oxidase negative and, with the exception of  Shigella dysenteriae  0 group 1 and  Xenorhabdus nematophilus , catalase positive. Nitrate is reduced to nitrite except by some strains of Erwinia and Yersina. The G+C content of DNA is 38-60 mol % (T m , Bd). DNAs from species from species within most genera are at least 20% related to one another and to  Escherichia coli , the type species of the family. Notable exceptions are species of Yersina, Proteus, Providenica, Hafnia and Edwardsiella, whose DNAs are 10-20% related to those of species from other genera. Except for  Erwinia chrysanthemi  all species tested contain the enterobacterial common antigen (Bergy&#39;s Manual of Systematic Bacteriology, D. H. Bergy, et al., Baltimore: Williams and Wilkins, 1984). 
     The term “transformation” refers to the stable acquisition of new genes in a cell following incorporation of nucleic acid. 
     “Transformant” refers to the strain that results from transformation. 
     Reporter genes 
     The preferred reporter gene for the present invention is the lux gene complex, responsible for bacterial bioluminescence and isolated from the bacteria  Photorhabdus luminescens . Bacterial bioluminescence is the phenomenon in which the products of 5 structural genes (luxA, luxB, luxC, luxD and luxE) work in concert to produce light. The luxD product generates a C 14  fatty acid from a precursor. The C 14  fatty acid is activated in an ATP dependent reaction to an acyl-enzyme conjugate through the action of the luxE product which couples bacterial bioluminescence to the cellular energetic state. The acyl-enzyme (luxE product) serves as a transfer agent, donating the acyl group to the luxC product. The acyl-LuxC binary complex is then reduced in a reaction in which NADPH serves as an electron pair and proton donor reducing the acyl conjugate to the C 14  aldehyde. This reaction couples the reducing power of the cell to bacterial light emission. The light production reaction, catalyzed by luciferase (the product of luxA and luxB), generates light. The energy for light emission is provided by the aldehyde to fatty acid conversion and FMNH 2  oxidation, providing another couple between light production and the cellular energy state. 
     The source of the bacteria lux complex was the pJT205 plasmid (formerly called pCGLS205) containing the  Photorhabdus luminescens  luxCDABE gene complex, fully described by (Rosson, R. A.,  PCT International Application WO  93/03179 (1993)). 
     Other reporter genes or gene complexes could also be used. Examples include but are not limited to the lux genes from marine microorganisms such as  Vibrio fischeri, Vibrio harveyi , or  Photobacterium phosphoreum , or the genes encoding luciferases from insects such as  Photinus pyralis  or  Pyrophorus plagiophthalamus  or the sea pansy,  Renilla reniformis.    
     Vectors 
     The invention provides a transformation vector containing a lux gene fusion, capable of transforming a bacterial host cell for the expression of the Lux proteins. A variety of transformation vectors may be used, however, those capable of transforming  E. coli  are preferred. pDEW201 is a specific example of a suitable transformation vector whose construction is given in detail in the following text. This vector represents only a sample of the total number of vectors created for the purpose of introducing promoter-lux reporter fusions into host cells. However, it will be readily apparent to one of skill in the art of molecular biology that the methods and materials used in their construction are representative of all other vectors described. 
     Transformation vectors such as these are common and construction of a suitable vector may be accomplished by means well known in the art. The preferred source of the lux genes is a pre-existing plasmid containing a promoterless lux gene complex. 
     Methods of creating gene fusions 
     The present invention provides a method for creating gene fusions where a gene regulatory region (typically comprising a promoter) is responsive to some cellular stress, is fused to a luminescent reporter gene complex. Fusions of the present invention may be created by a variety of methods in including partial restriction digests of genomic DNA, PCR, LCR or strand displacement amplification of known regions of the genome or by in vitro transposition. 
     Restriction Digests 
     The preferred method of generating gene fusions is isolation of chromosomal DNA from a bacterial species, partial digestion of that chromosomal DNA yielding overlapping fragments with a restriction enzyme such that compatible sticky ends to a site in the MCS of the plasmid vector are generated, size separation by agarose gel electrophoresis, isolation of the digested chromosomal DNA in particular size ranges, and ligation into the plasmid vector which had been digested with a restriction enzyme that cuts uniquely in the MCS. Any restriction enzyme or enzymes may be used that are specific to the genomic DNA employed and will give fragments of suitable size and having compatible ends for cloning into the appropriate vector. Restriction enzymes suitable for restriction of enteric bacterial are well known in the art (Sambrook, supra) and include AluI, AvrI, ValI, BamHI, AclI, BglI, ClaI, EcoRI, EcoRV, FokI, HaeII, HaeIII, HincII, HindIII, KnpI, MboI, MboII, NciI, NcoI, NdeI, NheI, NotI, PstI, PvuI, SacI, SacII, Sau3AI, Sau96I, SfiI, SmaI, XbaI, and XhoI. 
     PCR—primer directed methods 
     Gene fusions may alternatively be generated by methods of primer directed amplification if some or all of the sequence of the desired promoter or gene is known. Methods of primer directed amplification are well known in the art and include polymerase chain reaction (PCR), ligase chain reaction (LCR) or Strand Displacement Amplification (SDA). If PCR methodology is selected, the replication composition would include for example, nucleotide triphosphates, two primers with appropriate sequences, DNA or RNA polymerase and proteins. These reagents and details describing procedures for their use in amplifying nucleic acids are provided in U.S. Pat. No. 4,683,202 (1987, Mullis et al.) and U.S. Pat. No. 4,683,195 (1986, Mullis et al.). If LCR methodology is selected, then the nucleic acid replication compositions would comprise, for example, a thermostable ligase, e.g.,  T. aquaticus  ligase, two sets of adjacent oligonucleotides wherein one member of each set is complementary to each of the target strands, Tris HCl buffer, KCl, EDTA, NAD, dithiothreitol and salmon sperm DNA. (See, for example, Tabor, S. and Richardson, C. C. (1985)  Proc. Acad. Sci. USA  82, 1074-1078.). If the SDA methodology is used, amplification may be accomplished using either one or two short primers containing a site for HincII digestion, an exonuclease deficient DNA polymerase, HincII restriction enzyme and the bases dGTP, dCTP, dTTP and deoxyadenosine 5′[α-thio]triphosphate (dATP[αS]. The SDA protocol including the necessary materials is outlined in Walker et al. ( Proc. Natl. Acad. Sci. U.S.A.,  89:392 (1992)). 
     PCR methods could also be used to generate random segments of DNA if random primers are used with bacterial chromosomal DNA as the template. Such randomly amplified DNA segments (RAPD) would then be ligated into the MCS of the desired plasmid vector. 
     Transposons 
     Transposons may also be used to generate collections of gene fusions, using a process of in vivo transposition. Many transposable elements are available that have reporter genes lacking promoter sequences (Berg and Berg,  Transposable element tools for microbial genetics, in Escherichia coli and Salmonella Cellular and Molecular Biology , (2588-1612), F. C. Neidhardt, Editor. 1996, ASM Press: Washington, D.C.). Insertion of such transposons randomly throughout a bacterial chromosome will result in chromosomal promoters driving the expression of the reporter gene of the transposon. 
     Transformation of Suitable Hosts 
     Once suitable plasmids are constructed they are used to transform appropriate host cells. Introduction of the plasmid into the host cell may be accomplished by known procedures such as by transformation, e.g., using calcium-permeabilized cells, electroporation, transduction, or by transfection using a recombinant phage virus. (Sambrook et al., supra) 
     In the present invention, plasmid pDEW201 containing random chromosomal DNA was used to transform the  E. coli  DPD1675 as fully described in the GENERAL METHODS and EXAMPLES. 
     Transformed hosts—Detector organisms 
     Detector organisms may include a variety of both prokaryotic and eukaryotic organisms. Preferred are enteric bacteria; most preferred is  E. coli.    
     A suitable bacterial strain with which to test the effects of a chemical is one whose growth is affected by that chemical. Hence, the chemical of interest must be able to enter the cell, be retained in the cell, and interact with target molecules of the cellular machinery. Various mutations of  E. coli  are known to affect permeation into and accumulation within the cell. Strains carrying mutant alleles of rfa (Ames et al.,  Proc. Nat. Acad. Sci. USA,  70(3):782-786 (1973)), envA (Young and Silver,  J. Bacteriol.,  173:3609-3614 (1991)), imp (Sampson et al.,  Genetics,  122:491-501 (1989)), lpp (Giam et al.  J. Biol. Chem., ( 259):5601-5605 (1984) or surA (Tormo et al.,  J. Bacteriol., ( 172)4339-4347 (1990)) have increased sensitivity to a variety of chemicals. Destruction of efflux pumps, with mutations such as emr (Ma et al.,  Mol. Microbial.,  16:45-55 (1995)), or acrAB (Paulsen et al.,  Mol. Micro.,  19:1167-1175 (1996)), or the channels they use, with mutations such as tolC (Schnaitman et al.,  J. Bacteriol.,  172(9):5511-5513, (1990)), also result in increased chemical sensitivity. In some instances, the target macromolecule of a chemical may be intrinsically resistant to the action of that chemical. For example,  E. coli  has two isozymes of the enzyme acetolactate synthase (ALS), one of which has a poor binding affinity for the sulfonylurea herbicides. Mutations which destroy the functions of ilvBN, encoding the resistant isozyme, result in a strain with greatly increased susceptibility to growth inhibition by sulfonylurea herbicides that target acetolactate synthase (LaRossa and Smulski,  J. Bacteriol.,  160:391:394 (1984)). An appropriate host strain of  E. coli  or other bacteria may be constructed to carry a known mutation or combinations of mutations. Furthermore, an appropriately sensitive strain may also be found by screening for growth inhibition following mutagenesis by transposon insertion or chemical or physical treatments. 
     The present invention further provides a transformed host cell capable of increased luminescence in the presence of a cellular insult. Many suitable hosts are available where  E. coli  is preferred and the  E. coli  strain DPD1675 (ilvB2101 ara thi Δ(pro-lac)tolC::miniTn10) is most preferred. DPD1675 was derived by phage P1 mediated generalized transduction using a lysate growth on strain DE112 (strR, galK2, lac Δ74 tolC::miniTn10) as a donor and strain CU847 (ilvB2101 ara thi Δ(pro-lac)) as a recipient. Resultant tetracycline resistance transductants were screened for hypersensitivity to the hydrophobic compound crystal violet. 
     Cellular stress—Cellular Insults 
     The present invention provides a method for the detection of bacterial regulator elements responsive to a variety of cellular stresses (produced by cellular insults) such as those produced when a cell contacts chemicals, such as herbicides, crop protection chemicals, environmental pollutants, heavy metals, changes in temperature, changes in pH, agents producing oxidative damage, insults causing DNA damage, insults causing anaerobiosis, and biological insults such as the pathogenic life forms (viruses, bacteria, etc.). Preferred regulatory regions will be responsive to chemicals used in the agrochemical industry such as CPC&#39;s including herbicides. The regulatory regions identified include those responsive to sulfonylurea herbicides and sulfonanilide herbicides (chlorsulfuron, triasulfuron, metsulfuron-methyl) and glyphosate, phosphinothricin, asulam, and quizalofop. It is contemplated that regulatory regions responsive to other agrochemicals may also be identified by the present method including but not limited to pesticides (paraquat, copper sulfate, metidathion), anti-pathogenic compounds such as fungicides (chlorothalonil), chemicals responsible for insect behavior modulation (pheromones, allomonese and kairomones), auxin herbicides (e.g. dicamba, 2-methyl-4-chlorophenoxyacetic acid, picloram, quinclorac, quinmerac), pre-emergence herbicides (metribuzin), and post-emergence herbicides (Clethodim Pendimethalin, oryzalin, dithiopyr, oxadiazon, prodiamine, 2-4-D). 
     Culture Conditions 
     Typically cells are grown at 37° C. in appropriate media. Preferred growth media in the present invention are common defined media such as Vogel-Bonner medium (Davis et al.,  Advanced Bacterial Genetics  1980, Cold Spring Harbor, N.Y.:Cold Spring Harbor Laboratory). Other defined or synthetic growth media may also be used and the appropriate medium for growth of the particular microorganism will be known by someone skilled in the art of microbiology or fermentation process. 
     Suitable pH ranges for bacterial growth are between pH 5.0 to pH 9.0, where pH 6.0 to pH 8.0 is preferred as the initial condition. 
     Growth of the bacterial cells in liquid medium allows a uniform population of cells to be stressed at various growth phases such as early log phase, mid log phase, late log phase or stationary phase. Stress if the condition produced in a cell as the result of exposure to a cellular insult. This cellular insult may be caused by any substance or change in the cellular environment that results in an alteration of normal cellular metabolism in a bacterial cell or population of cells. The addition of chemicals such as herbicides, crop protection chemicals, environmental pollutants, or heavy metals to the growth media can cause such an insult. Additionally, changes in temperature, changes in pH, agents producing oxidative damage or DNA damage (such as from UV exposure), anaerobiosis, or changes in nitrate availability may cause insult as well. 
     Identification of regulatory regions 
     Genomic segments containing regulatory regions responsive to an cellular insult are identified by screening for altered luminescence following application of the cellular insult to individual isolates of the transformed host cells containing random chromosomal DNA fragments. A genomic segment is identified as containing a regulatory region it its presence upstream of the reporter gene(s) results in increased or decreased activity of the reporter gene(s) after application of the cellular insult to cells containing the genetic fusion. The genomic segment present in a particular plasmid is identified by the sequence of the ends of the chromosomal DNA fragment. The regulatory region, therefore, is a genomic segment located between those ends. Smaller genomic segments within that originally defined region will also likely be sufficient to function as the regulatory region. These smaller segments are identified by the altered activity of a reporter gene(s) following application of the environmental insult to cells containing a genetic fusion of the regulatory region to a reporter gene(s). The regulatory region may also be identified as the region responsible for altered messenger RNA or protein synthesis from the stress gene following application of the environmental insult to cells. 
     The application of the invention to discovery of  E. coli  genomic segments containing regulatory regions responsive to the herbicide sulfometuron methyl and 2,4-dichlorophenoxyacetic acid are described in detail in the GENERAL METHODS and EXAMPLES. A number of previously unidentified regulatory regions were discovered. These regulatory regions are contained within the chromosomal DNA fragment cloned into the multiple cloning site of pDEW201. However, it is likely that smaller segments of chromosomal DNA would be sufficient to function as the regulatory region. These are identified as the genomic segment responsible for increased transcription of the stress gene, which may be quantitated by increased activity of a reporter gene(s) in a genetic fusion, increased messenger RNA synthesis or increased protein synthesis. 
     Genomic segments containing regulatory regions responsive to other chemicals are found by this method also. In particular, it is expected to be useful to discover such segments responsive to crop protection chemicals that are known to inhibit metabolic processes that are in common to bacteria and plants. These would include, but are not limited to, glyphosate, an inhibitor of ESPS synthase (5-enolpyruvyl-shikimicacid-3-phosphate synthase)( Biochem. Biophys. Res. Commun.  94:1207-12 (1980)), phosphinothricin, an inhibitor of glutamate synthase (Baron et al.,  Plant Physiol. Biochem. (Paris)( 1994), 32(4):555-60), asulam (Kidd et al.,  Plant Sci. Lett.  (1982), 26(2-3), 211-17), a folate biosynthesis inhibitor, and quizalofop-ethyl, an inhibitor of acetyl CoA carboxylase (Dehaye et al.,  Eur. J. Biochem.  225:1113-23 (1994). 
     Discussion of the Preferred Embodiments 
     The data shown in FIGS. 2 and 3 demonstrate a key feature of this method: promoters of a wide range of activity are readily detected and quantitated by the resultant light production. An advantage of this method is that promoters of varied activities may all be measured with the same conditions at the same time. Furthermore, the activity of collections of such promoters can be screened for changes following cellular stress. An example, the SM induction of a strain identified by this method, is shown in FIG.  4 . It is not likely that this strain or others would have been identified by screening on plates, as typically done. This is shown in FIG. 6 where the bioluminescence of several strains identified by this method was recorded following growth on plates containing SM. Increases of bioluminescence on the SM-containing plates were not detected. This is may be in part because of the decreased amount of growth in the presence of the chemical. In fact, higher concentrations of SM (≧3 μg/mL) that were useful for characterizing fusion-containing strains in liquid medium could not be used on the plates because little to no growth resulted. 
     FIG. 6 shows another aspect of this invention. Various herbicidal chemicals were used to stress SM-inducible fusion containing strains identified by this method. A pattern of induction for each herbicidal chemical was observed. It was noted that two chemicals, SM and glyphosate, gave very similar patterns of induction. Thus, these fusion-containing strains may be useful as screens for compounds that will be effective herbicides. Furthermore, these fusion containing strains also may be useful for characterizing the modes of action of herbidcides or potential herbicides. 
     The present invention is further defined in the following Examples. It should be understood that these Examples, while indicating preferred embodiments of the invention, are given by way of illustration only. From the above discussion and these Examples, one skilled in the art can ascertain the essential characteristics of this invention, and without departing from the spirit and scope thereof, can make various changes and modifications of the invention to adapt it to various usages and conditions. 
     EXAMPLES 
     General Methods 
     Procedures for phosphorylations, ligation and transformations are well known in the art. Techniques suitable for use in the following examples may be found in Sambrook et al.,  Molecular Cloning: A Laboratory Manual,  Second Edition, Cold Spring Harbor Laboratory Press (1989). 
     Materials and methods suitable for the maintenance and growth of bacterial cultures are well known in the art. Techniques suitable for use in the following examples may be found in  Manual of Methods for General Bacteriology  (Phillipp Gerhardt, R. G. E. Murray, Ralph N. Costilow, Eugene W. Nester, Willis A. Wood, Noel R. Krieg and G. Briggs Phillips, eds), American Society for Microbiology, Washington, D.C. (1994) or Thomas D. Brock in  Biotechnology: A Textbook of Industrial Microbiology,  Second Edition (1989) Sinauer Associates, Inc., Sunderland, Mass. All reagents and materials used for the growth and maintenance of bacterial cells were obtained from Aldrich Chemicals (Milwaukee, Wis.), DIFCO Laboratories (Detroit, Mich.), GIBCO/BRL (Gaithersburg, Md.), or Sigma Chemical Company (St. Louis, Mo.) unless otherwise specified. 
     The meaning of abbreviations is as follows: “h” means hour(s), “min” means minute(s), “sec” means second(s), “d” means day(s), “mL” means milliliters, “L” means liters, μL means microliters, and μg means micrograms. 
     Example 
     1. Construction of a Promoter Probe Vector 
     Plasmid pDEW201 was made by replacing the promoterless lacZ gene of pRS415 (Simons et al.,  Gene,  53:85-96 (1987)) with the promoterless  Photorhabdus luminescens luxCDABE  from pJT205 (Rosson, PCT International Application WO 93/03179, 57 pp., (1993)). Plasmid pRS415 contains an origin of replication from pBR322, a bla gene and four tandem transcription terminators from phage T1 upstream of a multiple cloning site (MCS). This plasmid DNA was digested with BamH I, Nru I and EcoR V and ligated with pJT205 DNA that had been digested with BamH I, Pvu II and Pst I. The ligation mixture was used to transform  E. coli  strain DH5, selecting for ampicillin resistance. Light production from overnight cultures of transformant colonies that had been grown in LB medium containing 150 μg/mL of ampicillin was quantitated in a ML3000 luminometer in the presence and absence of 0.0033% nonanal. Plasmid DNA was isolated from three transformants that had very low levels of light production (0.0022 to 0.0029 RLU) in the absence of nonanal and moderate light production (0.91 to 0.97 RLU) in the presence of nonanal. Restriction digestion analysis with various enzymes and combinations of enzymes showed that each of these three plasmids had the expected structure except that a portion (c.a. 900 bp) near the 3′ terminus of the luxCDABE operon containing an EcoR I site was deleted. One of these plasmids was saved and named pDEW201. The entire luxCDABE operon is known to remain intact in pDEW201 because placement of DNA with promoter activity in the multiple cloning site results in light production in the absence of exogenously added aldehyde. Furthermore, DNA sequence analysis of the 3′ region of the lux operon in pDEW201 showed that the join point of the sequences derived from pJT205 to sequences derived from pRS415 was one nucleotide beyond the termination codon of luxE. 
     A map of plasmid pDEW201 is shown in FIG.  1 . Features of this plasmid include: (1) unique EcoR I, BamH I, Kpn I and Sac I sites in the multiple cloning site; (2) promoterless  Photorhabdus luminescence luxCDABE  genes downstream of the multiple cloning site; (3) transcription terminators upstream of the multiple cloning site resulting in a very low level of read-through transcription and hence very low light production in the absence of promoter DNA cloned into the multiple cloning site from cells containing this plasmid; (4) ampicillin resistance selection for maintenance of the plasmid; and (5) moderate copy number due to the replication origin from pBR322. 
     2. Construction of Libraries 
     Chromosomal DNA isolated from  E. coli  W3110 was partially digested with restriction enzyme Sau3 A1 and size fractionated on agarose gels. Fractions of three size ranges (average sizes of approximately 700, 1800 or 2500 basepairs) were ligated to pDEW201 that had previously been digested with restriction enzyme BamHI and treated with calf intestinal alkaline phosphatase. The ligation products were used to transform ultracompetent  E. coli  XL2Blue (Stratagene) to Amp R  (ampicillin resistant). Pooled transformants were cryogenically preserved and used to isolate plasmid DNA. 
     3. Characterization of Libraries of Cloned Random DNA Upstream of lux 
     Single ampicillin resistant transformants of  E. coli  XL2Blue were toothpicked from transformation plate to wells of a white microtiter plate containing 100 μl of LB medium (Miller,  Experiments in Molecular Genetics,  1972, Cold Spring Harbor, N.Y.: Cold Spring Harbor Laboratory). Light production was quantitated in an ML 3000 luminometer and compared with control pDEW201 transformants. Those with greater light production than the control were scored Lux + . The results are shown in Table I. 
     
       
         
               
               
               
               
             
           
               
                 TABLE I 
               
               
                   
               
               
                 Library 
                 approx. size of inserted DNA 
                 #Lux + /total picked 
                 % Lux +   
               
               
                   
               
             
             
               
                 Z 
                  500-2000 
                 21/88 
                 24% 
               
               
                 A 
                  900-3000 
                 49/88 
                 56% 
               
               
                 B 
                 1500-4500 
                 60/88 
                 68% 
               
               
                   
               
             
          
         
       
     
     As expected, there were a greater percentage of cloned fragments with promoter activity, hence light production, as the size of inserted DNA was increased. 
     Light production and insert size from 16 random individual transformants of libraries A and Z grown overnight in LB medium containing 150 μg/mL ampicillin was characterized. Bioluminescence from two 100 μL samples was quantitated, averaged and compared with the bioluminescence of pDEW201 transformants. The remaining 4.8 mL of the overnight culture was used to isolated plasmid DNA, which was subsequently digested with restriction enzymes EcoRI and SacI to release the fragment inserted into the MCS. Table II below summarizes the findings. 
     
       
         
               
               
               
               
               
               
             
           
               
                 TABLE II 
               
               
                   
               
               
                   
                   
                 range 
                   
                 Insert size 
                 Avg. 
               
               
                 Library 
                 Lux + /total 
                 of RLU 
                 Insert + /total 
                 range, kbp 
                 insert size 
               
               
                   
               
             
             
               
                 Z 
                  9/16 (56%) 
                 0.001-3.0 
                 16/16 
                 0.1-1.5 
                 0.7 kbp 
               
               
                   
                   
                   
                 (100%) 
               
               
                 A 
                 11/16 (69%) 
                 0.015-27 
                 16/16 
                 0.9-3.0 
                 1.8 kbp 
               
               
                   
                   
                   
                 (100%) 
               
               
                   
               
             
          
         
       
     
     FIGS. 2 and 3 display the light production as a function of insert size for these transformants. The large range of light production indicates that promoters of many strengths are present in the libraries. Furthermore, it demonstrates the advantages of the large dynamic range of the lux reporter in that these varied plasmids containing promoters of varied activities could all be measured with the same conditions at the same time. 
     4. Identification of Appropriate  E. coli  Host Strains 
     To discover the effects of chemicals on the cell without presupposition concerning the nature of those effects, the host strain should be as close to wild type as possible. Nevertheless, certain features are important. In order for the growth of  E. coli  to be inhibited by the sulfonylureas, such as sulfometuron methyl (SM), the SM-resistant ALS I must be eliminated by an ilvB −  mutation. Another desirable feature is increased sensitivity to chemicals.  E. coli  strains mutated in tolC lack the outer membrane channel for an hydrophobic compound efflux pump and thus are sensitive to growth inhibition at reduced chemical concentrations. The  E. coli  strain DPD1675 [ilvB2101 ara thi Δ(p{dot over (r)}o-lac) tolC::miniTn10], has both an ilvB −  mutation and a tolC −  mutation with few other mutations. 
     5. Screening for SM-inducible Promoters 
     Plasmid library A was used to obtain AmpR transformants of  E. coli  DPD1675. These transformants, each of which contained random, individual plasmids with  E. coli  DNA fused to the lux reporter, were toothpicked to wells of a microtiter plate. Each well contained 100 μL of Vogel-Bonner (Davis et al.,  Advanced Bacterial Genetics,  (1980), Cold Spring Harbor, N.Y.: Cold Spring Harbor Laboratory) with glucose as a carbon source and supplemented with thiamine, uracil, proline and 25 μg/mL ampicillin. Following overnight growth at 37° C., these pure cultures were used for both permanent storage (Menzel,  Anal. Biochem.,  181:40-50 (1989)) and dilution and regrowth to exponential phase in the same medium except containing 10 μg/mL ampicillin. These actively growing cultures were tested for the effects of SM addition by adding 50 μL to 50 μL of fresh medium lacking ampicillin but containing 4 μg/mL SM (E. I. du Pont de Nemours, Wilmington, Del.). The final SM concentration, 2 μg/mL, resulted in partial (25%) inhibition of  E. coli  DPD1675 growth rate. Light production was quantitated in a ML3000 luminometer at 0, 90, and 180 min of incubation at 37° C. after addition of cell cultures to chemical. The criteria of Table III were used to identify putative SM-inducible fusions. 
     
       
         
               
               
             
           
               
                 TABLE III 
               
               
                   
               
               
                 RLU (SM treated) − RLU (control) 
                 RLU (SM treated)/RLU (control) 
               
               
                   
               
             
             
               
                 ΔRLU 0.02 → 0.1 
                 Ratio ≧ 1.50 
               
               
                 ΔRLU 0.1 → 1.0 
                 Ratio ≧ 1.35 
               
               
                 ΔRLU 1.0 → 10.0 
                 Ratio ≧ 1.25 
               
               
                 ΔRLU &gt; 10.0 
                 Ratio ≧ 1.20 
               
               
                   
               
             
          
         
       
     
     Putative transformants were reisolated from the appropriate wells of the duplicate cultures stored at −80° C. and retested under the same conditions as above. Those that showed SM-induced increased bioluminescence in the second test were tested at third time at a variety of SM concentrations and for a longer extent of time. An example of induction of bioluminescence from one of these fusions is shown in FIG.  6 . Strains that continued to show good SM induction were selected for further analysis including DNA sequencing to identify the inserted DNA in the plasmid. Of the 8066 random fusion containing transformants that were screened, twenty were selected for DNA sequence analysis. 
     6. DNA Sequence Analysis 
     The DNA sequence information from both ends of the inserted DNA was analyzed by comparison with the  E. coli  chromosomal sequence using the ECDC database (Kröger and Wahl,  Nucleic Acids Res.: 24:29-31 (1996 )). A summary of the identities of the twenty inducible fusions is shown in Table IV. In all cases where the sequence was identified, the promoter closest to the lux reporter genes was situated such that the transcription initiated at that promoter would drive lux expression. The 17 single insert fusions represent 13 unique fusions of DNA with promoter activity to luxCDA{dot over (B)}E. 
     Sequence data was obtained by automated DNA sequencing. For those sequences labeled “upper” the primer, GGATCGGAATTCCCGGGGAT (SEQ ID NO: 27), from just upstream of the MCS of pDEW201 was used. For those sequences labeled “lower”, the primer, CTGGCCGTTAATAATGAATG (SEQ ID NO: 28), from the luxC region of pDEW201 was used. The sequences listed are those used for comparison with the  E. coli  sequence database. For the upper sequences, it starts about 30 bases into the sequence and continues to the first ambiguous base (N). For the lower sequences, it starts immediately after the BamHI site and continues to the first ambiguous base (N). In some cases, a few ambiguous bases (N) may be included. All sequences are shown 5′ to 3′. 
     
       
         
               
             
               
               
               
               
             
           
               
                 TABLE IV 
               
             
             
               
                   
               
               
                 DNA Sequence Analysis of 20 SM-Inducible Genes 
               
             
          
           
               
                   
                 Sub- 
                   
                 Other 
               
               
                 Total 
                 fusions 
                 Categories 
                 Information 
               
               
                   
               
               
                 3 
                 — 
                 Double insert =&gt; 
                   
               
               
                   
                   
                 No further analysis 
                   
               
               
                   
                   
                 (3 of 3 fusions) 
               
               
                 3 
                 — 
                 No hits to database 
               
               
                   
                   
                 (3 of 3 fusions) 
               
               
                   
                   
                 Unique (1 of 3 
               
               
                   
                   
                 fusions) Identical 
               
               
                   
                   
                 to each other (2 of 3 
               
               
                   
                   
                 fusions) 
               
               
                 4 
                 — 
                 Hit at one end only 
                 Downstream of ack 
               
               
                   
                   
                 (4 of 4 fusions) 
                 Downstream of glk 
               
               
                   
                   
                 (upper primer 
               
               
                   
                   
                 sequence) 
               
               
                   
                   
                 51.49 min  
               
               
                   
                   
                 (1 of 4 fusion) 
               
               
                   
                   
                 52.31 min 
               
               
                   
                   
                 (3 or 4 fusions) 
               
               
                 6 “unknown” orfs 
               
               
                   
                 1 ldcH 
                 4.5 min 
                 Predicted function: 
               
               
                   
                   
                   
                 lysine decarboxylase 
               
               
                   
                 1 yciG 
                 28.2 min 
                 Predicted function: 
               
               
                   
                   
                   
                 unknown 
               
               
                   
                 2 yohF 
                 47.4 min 
                 Predicted function: 
               
               
                   
                   
                   
                 dehydrogenase 
               
               
                   
                 1 yiaB 
                 80.3 min 
                 Predicted function: 
               
               
                   
                   
                   
                 unknown 
               
               
                   
                 1 frvx 
                 88.1 min 
                 Predicted function: 
               
               
                   
                   
                   
                 unknown 
               
               
                 4 known genes 
               
               
                   
                 1 poxB 
                 19.6 min 
                 Pyruvate oxidase 
               
               
                   
                   
                   
                 Regulated by rpoS 
               
               
                   
                 1 inaA 
                 50.0 min 
                 Function: not known 
               
               
                   
                   
                   
                 Induced by acid shock 
               
               
                   
                   
                   
                 and other environ- 
               
               
                   
                   
                   
                 mental insults Reg- 
               
               
                   
                   
                   
                 ulated by soxRS and 
               
               
                   
                   
                   
                 mar 
               
               
                   
                 1 sohA 
                 70.6 min 
                 Activation of the Lon 
               
               
                   
                   
                   
                 protease Auto 
               
               
                   
                   
                 a.k.a. prlF 
                 regulated 
               
               
                   
                 1 osmY 
                 99.3 min 
                 Periplasmic protein 
               
               
                   
                   
                   
                 induced by hyper- 
               
               
                   
                   
                   
                 osmotic insult 
               
               
                   
                   
                   
                 Regulated by rpoS, 
               
               
                   
                   
                   
                 lrp, cAMP, and IHF 
               
               
                   
               
             
          
         
       
     
     7. Functional Grouping of Fusion Containing Strains 
     Each of the 13 unique single insert fusion strains was characterized by testing actively growing cells in Vogel-Bonner medium with glucose as the carbon source supplemented with thiamine, proline and uracil challenged with final concentration of chemicals: 3 or 8 μg/mL SM or 5 mM salicylate, a weak, membrane-permeant acid. Bioluminescence was quantitated for ≧1000 min in an ML3000 luminometer at 37° C. in plates covered with acetate seals. Data from plots of RLU vs. time were analyzed calculating “very early” induction ratios and “peak” response ratios. The ratio of the RLU from treated samples (with SM 3 μg/mL or Salicylate 5 mM) at the 90 min time point to the control RLU at the 90 min time point was the “very early” induction ratio; the fusion was considered induced if this ratio was &gt;1.3. The ratio of the peak RLU of treated cells (with SM 8 μg/mL or Salicylate 5 mM) at any time point in the experiment to the peak RLU at any time point of the control cells was the “peak” response ratio; the fusion was considered induced if this ratio was &gt;1.5. Also calculated was the ratio of the RLU peak of the untreated cells to the RLU of the untreated cells at the second cycle (1000 sec) of the experiment. Table V shows the classes of fusions from this data. 
     
       
         
               
             
               
               
               
               
               
               
             
               
             
               
               
               
               
               
               
             
               
             
               
               
               
               
               
               
             
               
             
               
               
               
               
               
               
             
               
             
               
               
               
               
               
               
             
               
             
               
               
               
               
               
             
           
               
                 TABLE V 
               
               
                   
               
               
                 Classes of fusion strains 
               
               
                   
               
             
             
               
                 “Class 1” Stationary phase inducible (and putatives) 
               
             
          
           
               
                   
                   
                 SM 
                 Salicylate 
                 Overnight 
                 Genomic 
               
               
                   
                   
                 induction 
                 induction 
                 peak/initial 
                 Segment 
               
               
                   
                   
                 RLU (SM)/ 
                 RLU (Sal.)/ 
                 RLU (second 
                 bounded by 
               
               
                 Strain 
                 Fusion 
                 RLU control 
                 RLU control 
                 cycle) 
                 SEQ ID NOS: 
               
               
                   
               
               
                 DPD3509 
                 poxB′::lux 
                 Very early only: 
                 Very early only: 
                 17/0.5 = 34X 
                 23 and 24 
               
               
                   
                 (pyruvate oxidase) 
                 1.9/1.3 = 1.5 X 
                 2.9/1.3 = 2.2X 
               
               
                 DPD2090 
                 osmY′::lux 
                 Very early only: 
                 Very early only: 
                 1.6/0.05 = 32X 
                 13 and 14 
               
               
                   
                 (outer membrane 
                 0.12/0.08 = 1.5X 
                 0.12/0.08 = 1.5X 
               
               
                   
                 protein) 
               
               
                 DPD2088 
                 yohF′::lux 
                 Very early: 
                 Very early only: 
                 4.3/0.2 = 22X 
                 9 and 10 
               
               
                   
                 (putative dehydro- 
                 0.6/0.3 = 2X 
                 0.6/0.3 = 2X 
               
               
                   
                 genase) 
                 Late (slight): 
               
               
                   
                   
                 7.4/4.3 = 1.7X 
               
               
                 DPD3505 
                 unmapped 
                 Very early only: 
                 Not induced 
                 7.2/0.35 = 21X 
                 19 and 20 
               
               
                   
                 (no clues from 
                 1.1/0.7 = 1.6X 
               
               
                   
                 protein database) 
               
               
                   
               
             
          
           
               
                 “Class 2” Acid inducible (and putatives) 
               
             
          
           
               
                   
                   
                   
                   
                 Overnight 
                 Genomic 
               
               
                   
                   
                   
                   
                 peak/initial 
                 Segment 
               
               
                   
                   
                 SM 
                 Salicylate 
                 RLU (second 
                 bounded by 
               
               
                 Strain 
                 Fusion 
                 induction 
                 induction 
                 cycle) 
                 SEQ ID NOS: 
               
               
                   
               
               
                 DPD2087 
                 inaA′::lux 
                   
                 Very early 
                 90/10 = 9X 
                 7 and 8 
               
               
                   
                 (acid inducible, 
                   
                 (strong): 
               
               
                   
                 unknown func.) 
                 Moderate late: 
                 130/25 = 5.2X 
               
               
                   
                   
                 200/90 = 2.2X 
                 Late: 
               
               
                   
                   
                   
                 325/90 = 3.6X 
               
               
                 DPD3507 
                 sohA′::lux 
                   
                 Very early: 
                 80/10.5 = 7.6X 
                 21 and 22 
               
               
                   
                 (Lon activator) 
                   
                 42/22 = 1.9X 
               
               
                   
                   
                 Moderate late: 
                 Late (Slight): 
               
               
                   
                   
                 160/80 = 2X 
                 155/80 = 1.9X 
               
               
                 DPD3501 
                 frvX′::lux 
                   
                 Very early: 
                 10/1.2 = 8.3X 
                 17 and 18 
               
               
                   
                 (unknown function) 
                   
                 4/2.6 = 1.5X 
               
               
                   
                   
                 Moderate late: 
                 Late (Slight): 
               
               
                   
                   
                 24/10 = 2.4X 
                 17.5/10 = 1.8X 
               
               
                 DPD2089 
                 unmapped 
                 Very early: 
                 Very early: 
                 18/6 = 3X 
                 11 and 12 
               
               
                   
                 (no clues from 
                 11.0/7.5 = 1.5X 
                 19.5/7.5 = 2.6X 
               
               
                   
                 protein database) 
                 Moderate late: 
                 Late (Slight): 
               
               
                   
                   
                 55/18 = 3.1X 
                 30/18 = 1.7X 
               
               
                 DPD3512 
                 ldcH′::lux 
                 Very early: 
                 Very early: 
                 2.5/0.38 = 6.6X 
                 25 and 26 
               
               
                   
                 (putative lysine 
                 1.2/0.6 = 2X 
                 1.05/0.6 = 1.8X 
               
               
                   
                 decarboxylase) 
                 Moderate late: 
                 Late (Slight): 
               
               
                   
                   
                 10.2/2.5 = 4.1X 
                 4.5/2.5 = 1.8X 
               
               
                   
               
             
          
           
               
                 “Class 3” Stationary phase (very strong) and acid inducible (putative) 
               
             
          
           
               
                   
                   
                   
                   
                 Overnight 
                 Genomic 
               
               
                   
                   
                   
                   
                 peak/initial 
                 Segment 
               
               
                   
                   
                 SM 
                 Salicylate 
                 RLU (second 
                 bounded by 
               
               
                 Strain 
                 Fusion 
                 induction 
                 induction 
                 cycle) 
                 SEQ ID NOS: 
               
               
                   
               
               
                 DPD2092 
                 downst. of ack 
                 Very early: 
                   
                 15/0.06 = 250 
                 15 and 16 
               
               
                   
                 (putative 
                 0.99/0.72 = 1.4X 
               
               
                   
                 transmembrane 
                 Late: 
                 Late only: 
               
               
                   
                 protein) 
                 130/15 = 8.7X 
                 50/15 = 3.3X 
               
               
                   
               
             
          
           
               
                 “Class 4” Possible SM-specific induction 
               
             
          
           
               
                   
                   
                   
                   
                 Overnight 
                 Genomic 
               
               
                   
                   
                   
                   
                 peak/initial 
                 Segment 
               
               
                   
                   
                 SM 
                 Salicylate 
                 RLU (second 
                 bounded by 
               
               
                 Strain 
                 Fusion 
                 induction 
                 induction 
                 cycle) 
                 SEQ ID NOS: 
               
               
                   
               
               
                 DPD2084 
                 yciG′::lux 
                 Very early: 
                 Not induced 
                 0.7/0.09 = 7.8X 
                 3 and 4 
               
               
                   
                 (unknown function) 
                 0.18/0.11 = 1.6X 
               
               
                   
                   
                 Moderate late: 
               
               
                   
                   
                 1.5/0.7 = 2.1X 
               
               
                 DPD2086 
                 yiaB′::lux 
                 Very early only 
                 Not induced 
                 0.45/0.085 = 5.3X 
                 5 and 6 
               
               
                   
                 (unknown function) 
                 (v. slight): 
               
               
                   
                   
                 0.17/0.15 = 1.1X 
               
               
                   
               
             
          
           
               
                 “Class 5” Generally inducible by many stresses 
               
             
          
           
               
                   
                   
                   
                   
                 Overnight 
                 Genomic 
               
               
                   
                   
                   
                   
                 peak/initial 
                 Segment 
               
               
                   
                   
                 SM 
                 Salicylate 
                 RLU (second 
                 bounded by 
               
               
                 Strain 
                 Fusion 
                 induction 
                 induction 
                 cycle) 
                 SEQ ID NOS: 
               
               
                   
               
               
                 DPD2081 
                 downst of glk 
                 Very early: 
                 Early: 
                 0.35/0.2 = 1.8X 
                 1 and 2 
               
               
                   
                 (putative fructose 
                 0.5/0.2 = 2.5X 
                 0.35/0.2 = 1.8X 
               
               
                   
                 specific iic 
                 Late: 
                 Late: 
               
               
                   
                 component of pts) 
                 3.6/.35 = 10.3X 
                 1.5/0.35 = 4.3X 
               
               
                   
               
             
          
           
               
                 “Control” Non-SM inducible, heat shock promoter 
               
             
          
           
               
                   
                   
                   
                   
                 Overnight 
               
               
                   
                   
                   
                   
                 peak/initial 
               
               
                   
                   
                 SM 
                 Salicylate 
                 RLU (second 
               
               
                 Strain 
                 Fusion 
                 induction 
                 induction 
                 cycle) 
               
               
                   
               
               
                 DPD2077 
                 grpE′::lux 
                 None 
                 Very early: 
                 340/48 = 7.1X 
               
               
                   
                   
                   
                 250/80 = 3.1X 
               
               
                   
                   
                   
                 Moderate late: 
               
               
                   
                   
                   
                 700/340 = 2.1X 
               
               
                   
               
             
          
         
       
     
     8. Induction by Other Herbicides 
     Representative fusions from some of the classes above were tested for induction by other herbicidal compounds. Strains DPD3509 (poxB′::luxCDABE), DPD2087 (inaA′::lux), and DPD2081 (map position of fusion is downstream of glk) were grown in Vogel-Bonner medium with glucose as the carbon source supplemented with thiamine, proline and uracil until mid-log phase. These cultures were challenged with SM, glyphosate (Sigma, St. Louis, Mo.), phosphinothricin, asulam, or quizalofop-ethyl (Chem Services, West Chester, Pa. 19381). Bioluminescence was quantitated for &gt;1000 min in an ML3000 luminometer at 37° C. in plates covered with acetate seals. Data from plots of RLU vs. time were analyzed calculating “early” and “peak” responses. The difference of the RLU from treated samples (SM 8 μg/mL, glyphosate 100 μg/mL, phosphinothricin 200 μg/mL, asulam 50 μg/mL or quizalofop-ethyl 50 μg/mL at the 200 min time point from the control RLU at the 200 min time point was normalized by dividing by the RLU of the control sample at that time point to give the “early” response:            RLU                   (     treated   ,     200                 min       )       -     RLU                   (     control   ,     200                 min       )           RLU                   (     treated   ,     200                 min       )                              
     The difference of the peak RLU of treated cells (SM 16 μg/mL, glyphosate 100 μg/mL, phosphinothricin 200 μg/mL, asulam 50 μg/mL or quizalofop-ethyl 50 μg/mL) at any time point in the experiment to the peak RLU at any time point of the control cells was normalized by dividing by the peak RLU of the control sample to give the “peak” response:            RLU                   (     treated   ,   peak     )       -     RLU                   (     control   ,   peak     )           RLU                   (     treated   ,   peak     )                              
     FIG. 5 displays the results of these calculations; values less than zero are not shown. Each herbicide gives a pattern of induction of these three fusions that is unique. However, the similarity of pattern between SM and glyphosate is noted. 
     9. Bioluminescence Detection on Plates 
     The described method of discovery of promoters by inducing stress in cells growing in liquid medium is more sensitive than assessing activity of the reporter genes on petri plates. This was shown by testing several of the SM-induced fusion containing strains.  E. coli  strains DPD2084, DPD2081, DPD2088, DPD3512, and DPD2092 were streaked for single colonies on Vogel-Bonner medium agar plates with glucose as the carbon source and supplemented with thiamine, proline, uracil and ampicillin (25 μg/mL). Six single colonies of each were transferred with a toothpick to the plates of the same composition except lacking ampicillin and containing SM at 2 μg, 1 μg/mL, 0.5 μg/mL or 0 μg/mL. Following incubation at 37° C. overnight, there was visible growth on all plates; however, the growth on the plates containing SM was visibly less dense. These plates were exposed to X-ray film (DuPont REFLECTIONS, Wilmington, Del.) at 37° C. for two h. The film was developed and examined visually. There was no increase in darkening of the film for any of these five strains on the plates with SM compared with those plates lacking SM. An image of the exposed and developed X-ray film was made by illuminating it on a light box, capturing an electronic image using the Eagle Eye™ II (Stratagene) system. Colors corresponding to the various exposures of the film were added to the image using a Macintosh QUADRA 800 computer and the public domain NIH Image program (written by Wayne Rasband at the U.S. National Institutes of Health and available from the Internet by anonymous ftp from zippy.nimh.nih.gov or on floppy disk from NTIS, 5285 Port Royal Rd., Springfield, Va. 22161, part number PB93-504868). These version of the relative bioluminescence of these  E. coli  strains grown on plates is shown in FIG.  6 . As with visual examination of the film, there is no evidence of increased bioluminescence on the plates with SM compared with those plates lacking SM. Thus, it is unlikely that any of these five strains would have been scored SM-inducible by a plate assay. 
     10. Identification of Regulatory Regions Responsive to 2,4-dichlorophenoxyacetic Acid 
     This method is also useful for discovery of regulatory regions modulated by other chemicals. This was shown by identification of fusion-containing strains showing bioluminescence which was inducible by the herbicidal compound 2,4-Dichlorophenoxyacetic acid. Plasmid libraries Z, A, and B were used to obtain ampicillin resistant transformants of  E. coli  DPD1675. These transformants, each of which contained random, individual plasmids with  E. coli  DNA fused to the lux reporter, were grown in wells of a microtiter plate. Each well contained 100 μL of Vogel-Bonner medium (Davis et al.,  Advanced Bacterial Genetics,  (1980), Cold Spring Harbor, N.Y.: Cold Spring Harbor Laboratory) with glucose as a carbon source and supplemented with thiamine, uracil, proline and 25 μg/mL ampicillin. Following overnight growth at 37° C., these pure cultures were used for dilution and regrowth to exponential phase in the same medium except containing 10 μg/mL ampicillin. These actively growing cultures were tested by adding 50 μl to 50 μL of fresh medium lacking ampicillin but containing 100 μg/mL 2,4-Dichlorophenoxyacetic acid (Janssen Chimica). The final 2,4-Dichlorophenoxyacetic acid concentration was 50 μg/mL. Light production was quantitated in a ML3000 luminometer at 0, 1, 2, and 3 hours of incubation at 37° C. after addition of cell cultures to chemical. Eighty-eight transformants from each library (Z, A, and B) were tested. The Ratio of RLU in the treated sample to RLU in the untreated sample was calculated, as was the difference in RLU of the treated sample from the untreated. Fusion-containing strains which gave a ratio greater than or equal to 1.2 and an increase in RLU greater than 0.1 were scored as 2,4-Dichlorophenoxyacetic acid-inducible. Table VI list the results of 2,4-Dichlorophenoxyacetic acid-inducible isolated identified. 
     
       
         
               
               
               
               
               
             
           
               
                 TABLE IV 
               
               
                   
               
               
                 Gene fusion 
                   
                 Time of 
                   
                   
               
               
                 Library 
                 Isolate # 
                 Treatment 
                 Ratio 
                 Increase in RLU 
               
               
                   
               
             
             
               
                 Z 
                 Z1-C4 
                 1 h 
                 2.1 
                 2.5 
               
               
                   
                 Z1-E11 
                 1 h 
                 1.2 
                 2.0 
               
               
                   
                 Z1-C11 
                 2 h 
                 1.5 
                 0.3 
               
               
                 A 
                 A1-H2 
                 1 h 
                 1.3 
                 25.2 
               
               
                   
                 A1-F7 
                 1 h 
                 1.2 
                 4.5 
               
               
                 B 
                 B1-D3 
                 2 h 
                 1.3 
                 23.9 
               
               
                   
                 B1-A8 
                 3 h 
                 1.3 
                 0.3 
               
               
                   
                 B1-E8 
                 3 h 
                 1.7 
                 14.1 
               
               
                   
                 B1-F9 
                 2 h 
                 1.4 
                 1.8 
               
               
                   
               
             
          
         
       
     
     
       
         
           
             28 
           
           
             
               150 base pairs 
               nucleic acid 
               single 
               linear 
             
             
               DNA (genomic) 
             
             
               unknown 
               DPD2081 upper 
             
             1
TTTGGTGGCG CAGAACCGGT CGAAGGTAAG CCTATTGCGG TTTACGGTGC CGGAACGGGG     60
CTTGGGGTTG CGCATCTGGT CCATGTCGAT AAGCGTTGGG TAAGCTTGCC AGGCGAAGGC    120
GGTCACGTTG ATTTTGCGCC GAATAGTGAA                                     150 
           
           
             
               95 base pairs 
               nucleic acid 
               single 
               linear 
             
             
               DNA (genomic) 
             
             
               unknown 
               dpd2081 lower 
             
             2
CCCATTGCGT ACATCAGCGC GCCCTTCTCA CCTGCGGCAG TCAGCACAGT ACGGATACCG     60
CCGTTGATCC AGCCACCAAA GGGGGTGATG ACGTA                                95 
           
           
             
               414 base pairs 
               nucleic acid 
               single 
               linear 
             
             
               DNA (genomic) 
             
             
               unknown 
               dpd2084 upper 
             
             3
ATTCAAAACG CCACTCTGCG CGCCTTTGCG GCAGGTGTGA CTCCGGCACA ATGTTTTGAA     60
ATGCTGGCAC TGATTCGCCA GAAACACCCG ACCATTCCCA TTGGCCTGTT GATGTATGCC    120
AATCTGGTGT TTAACAAAGG CATTGATGAG TTTTATGCCC AGTGCGAAAA AGTCGGCGTC    180
GATTCGGTGC TGGTTGCCGA TGTGCCAGTT GAAGAGTCCG CGCCCTTCCG CCAGGCCGCG    240
TTGCGTCATA ATGTCGCACC TATCTTCATC TGCCCGCCAA ATGCCGATGA CGACCTGCTG    300
CGCCAGATAG CCTCTTACGG TCGTGGTTAC ACCTATTTGC TGTCACGAGC AGGCGTGACC    360
GGCGCAGAAA ACCGCGCCGC GTTACCCTCA ATCATCTGGT TGCGAACTGA AAGA          414 
           
           
             
               283 base pairs 
               nucleic acid 
               single 
               linear 
             
             
               DNA (genomic) 
             
             
               unknown 
               dpd2084 lower 
             
             4
ATTTTTAAAA TTACCGCCGC TATGCTGACC GCCTTTACGG CCTGCGTCGG ATGCCTTCTC     60
ACGGTCTTCG GCGAAATTTC CTGAACCACC ACGATGTTCG GCCATGTTAT TTCTCCCGTT    120
GCGTTGCATT GTTTCATTAA TATGAGTGTT GTGTGTCGAC ACTCATTAAA ATTAGTCGCT    180
AATGAGAATT AGTCAAATTA AGCGCAACGA GAAGATAGAG GGAAAATATA TTTTGAGGAA    240
CATTCTGGAT ATATTAACAA TTACCTGAGG AATAAGTGAC TTA                      283 
           
           
             
               185 base pairs 
               nucleic acid 
               single 
               linear 
             
             
               DNA (genomic) 
             
             
               unknown 
               dpd2086 upper 
             
             5
CGCGATGGAT ACGATGGCAC TGGCGCTGAA ATTGCGCGCG CATGATTGAA ATGGCAAGCT     60
GGAAAACGCA TCGCGCACGT TATTCCGGCA TGGAATAACG AATTGGGCCA CCAAATCCGA    120
AAGGCCGGTG TCACTGGCAA TTTAGCCAAA TATGCTCAGG AACATCATGT GTCTCCGGTG    180
CATCA                                                                185 
           
           
             
               479 base pairs 
               nucleic acid 
               single 
               linear 
             
             
               DNA (genomic) 
             
             
               unknown 
             
             6
TCCATATCTA CCAGCGATAC ATTACGAGTA ACCAACGAAA GACAAAACTG AAAAATGCCA     60
TTAACAAATG ATTTTCAGAA TAAATTCATA CTAAATATTA ATTAATTACT GAGATATATA    120
GATGTGAATT ATCCCCCACC CGGTCAGGCA GGGGATAACG TTTACGCCAT TAATGGCAGA    180
AGTTGCTGAT AGAGGCGACG GAACGTTTCT CGTCGTGGCT GATAAGCGGC ATAACGCTGC    240
GCATCTGGTA GATGCGACTG TTCTAACGGT AGTTGCGGCA ACAATTCAAT GAGCGATTTC    300
TCTGGATTCG CCGCGATCTG CGCCAGCCTT GCTGCGCCCA GTGCTGGCCC CACATCCCCC    360
CCCGTACGGT AATCGAGCTG CTGACCGCTG ATATCCGCCA GCATCTGACG CCAGTACTCA    420
CTACGCGCCC CGCCCCCAAT CAACGTAACA CTTTGCGGTT TAATACCGCA GGCATGCAC     479 
           
           
             
               533 base pairs 
               nucleic acid 
               single 
               linear 
             
             
               DNA (genomic) 
             
             
               unknown 
               dpd2087 upper 
             
             7
TCGTTACTAC GCGATAGATT TCACGCTGGA TGAAATTAAG TCGTTGAAAT TTACCGAAGG     60
TTTCGATATT GAAAACGGTA AAAAAGTGCA GACTTATCCG GGGCGTTTCC CAATGGGTAA    120
GTCCGACTTC CGGGTGCACA CCTTTGAAAA AGAGATTGAA TTTGTTCAGG GGTTAAATCA    180
CTCTACCGGG AAAAATATCG GTATTTATCC AGAAATCAAA GCGCCGTGGT TCCATCATCA    240
GGAAGGGAAG GATATTGCGG CAAAAACGCT GGAAGTGCTG AAGAAATATG GTTACACCGG    300
TAAAGACGAT AAAGTTTATT TGCAATGTTT TGATGCTGAT GAGCTGAACG TATTAAGAAT    360
GAGCTGGAAC CCAAAATGGG CATGGAGCTC AATCTGGTAC AGCTGATTGC CTATACCGAC    420
TGGAATGAAA CGCAGCAGAA ACAGCCGGAT GGAACTGGGT TAATTACACT ACGACTGGAT    480
GTTTAACCGG GTGCCATGAA ACAGGTGGCG GAATATGCAG ATGGTATTGG TCC           533 
           
           
             
               183 base pairs 
               nucleic acid 
               single 
               linear 
             
             
               DNA (genomic) 
             
             
               unknown 
               dpd2087 lower 
             
             8
TTCGGCACGA TGACACCGGC CCGTTCCAGT TCTTTAATTA CCGCAACCTC ACGGACAATC     60
GTTGGTCGGC CGAACGGATA ACGTACGGAA TGAAACAGAT GATGCGTCAT GCGCTTTACA    120
TACAGCTTTT TGCCGTTGCG CTCGACGCAT TGCACCCCGC TCATACCATT ACGGCGATAG    180
TTA                                                                  183 
           
           
             
               174 base pairs 
               nucleic acid 
               single 
               linear 
             
             
               DNA (genomic) 
             
             
               unknown 
               dpd2088 upper 
             
             9
CAGTGATGAT TGGTCGCGGG GCGCTCAATA TTCCCAACCT GAGCCGGGTG GTAAAATATA     60
ACGAACCGCG AATGCCGTGG CCGGAGGTGG TTGCTTTGCT GCAAAAATAT ACCCGTCTGG    120
AAAAGCAGGG CGATACCGGG TTATATCACG TTGCGCGGAT TAAACAGTGG TTGA          174 
           
           
             
               219 base pairs 
               nucleic acid 
               single 
               linear 
             
             
               DNA (genomic) 
             
             
               unknown 
               dpd2088 lower 
             
             10
CCGAATCGGA GGCGGTAATA ATCGCAACCT GTGCCATCGA GTTCTCCACT TAACGCTGAA     60
TAAACGTTAA GTATAGAAGG CGCATATCAT CAGCGTTTGT ACCCCCCGCC CAACGCACCA    120
GTGAGTTGAA TGGAGGCATC CAGCCACTGC CCTTGCAATA ACAGGCCATT GGCCCGCTCA    180
CGCAGCGCGG GGATTCTGGC TTCGCTGACG CGGGAACCA                           219 
           
           
             
               229 base pairs 
               nucleic acid 
               single 
               linear 
             
             
               DNA (genomic) 
             
             
               unknown 
               dpd2089 upper 
             
             11
GATTTGCTAT CGAAACCATT CTCATTTTTG TGACAGGTTC GTCGTCACTA TATGGCTACG     60
ATAAATAAGG GTGGTAAGCA TTAACAATCC AGGGTAATGG GTGAGGCGAG AGTAAGACGG    120
TAACAGACAT ATCTTCTTGT GTCTTTCTTT TAATACCAAA ACATAACCGT TTCTTACATT    180
GATAAAAAAT GGAAAAAGTT GAACACTAGT TGGCGAAAAA TCTTGTATA                229 
           
           
             
               205 base pairs 
               nucleic acid 
               single 
               linear 
             
             
               DNA (genomic) 
             
             
               unknown 
               dpd2089 lower 
             
             12
TAACCCATTA ATTATTGAGC ATAATGTAGG CAGTACAAAA TAAGTTAGGC GGGATATCAG     60
GCGTCAAGAA TGGAACGAGA ACTCTCCATT CTTGACACCT GATATTGCGG ACATAATAAG    120
AAAGCATAAC GCCTGAAATG CTCACTTTGC ATCAGCATGG TGATACAGCT GATGTTTATT    180
CTAAAACCTT ACTCAAGTTC TAAGA                                          205 
           
           
             
               186 base pairs 
               nucleic acid 
               single 
               linear 
             
             
               DNA (genomic) 
             
             
               unknown 
               dpd2090 upper 
             
             13
GCTTTCCGAA GAGGGCGCGG TGCAGGTGTT CCGTCCAATC TCCAACAACG ATCTGATCGT     60
TGGTGCAGTT GGTGTGCTGC AGTTTGATGT GGTGGTAGCG CGCCTGAAGA GCGAATACAA    120
CGTTGAAGCA GTGTATGAGT CAGTCAACGT TGCCACTGCC CGCTGGGTAG AATGTGCAGA    180
CGCGAA                                                               186 
           
           
             
               507 base pairs 
               nucleic acid 
               single 
               linear 
             
             
               DNA (genomic) 
             
             
               unknown 
               dpd2090 lower 
             
             14
CACCAGGGCC GCCTTCACTT TCGCGGTGAT GGCGCTGTCA TCCATGAAAT TACCGACTTT     60
ATTCATAGAG CTATCGACTT TTTGCCCTGC GCTTTCATTG GTAGTCTGCG CGTTGTTTTC    120
CGCGTAGGCA GAGCCGGTCG CGACGGCAGA GGTCAACATT ACAGCCAGCA GAGTTTTCGA    180
AATCTTCAGT CTTGTCATAG TCATCGATTT ATTCCTGTAT GTTTGCTCGT AATTTGAGCC    240
TGGCAACACG AGGTTGCATT GCTGAATAGG GAGAGACTTC ACCCTCTACA GAAGTCAATG    300
GTCGCCATCA CAAAAGCGAT GAGTGATGAA TAACGACCAT TACAGCCTCT GAATCAGTTA    360
TTAATATCGG TAGAATGACA ATCGACGGCT TTAGATACTG ATATCTACGC ATTGAACGGT    420
ATTTAACGCC GTCAGAAATG TCATCACTTT GTTAAATATA GATCACAATT TTGAAACCGC    480
TCGGGATATC ACGAAACATA ACAAAAT                                        507 
           
           
             
               428 base pairs 
               nucleic acid 
               single 
               linear 
             
             
               DNA (genomic) 
             
             
               unknown 
               dpd2092 upper 
             
             15
CAAGCCGGTT AACGACCTGT CCCGTGGCGC ACTGGTTGAC GATATCGTCT ACACCATCGC     60
GCTGACTGCG ATTCAGTCTG CACAGCAGCA GTAATCTCGC ATCATCCGCA GCTTTGCGCT    120
GCGGATATCT GAACCGGAAA TAATCACTAT TTCCGGTTTT TTATTCTCTT AATTTGCATT    180
AATCCTTTCT GATTATCTTG CTTAACTGCG CTGCATCAAT GAATTGCGCC ATCCCACTTT    240
GCATACTTAC CACTTTGTTT TGTGCAAGGG AATATTTGCG CTATGTCCGC AATCACTGAA    300
TCCAAACCAA CAAGAAGATG GGCAATGCCC GATACGTTGG TGATTATCTT TTTTGTTGCT    360
ATTTTAACCA GCCTTGCCAC CTGGGTAGTT CCGGTGGGGA TGTTTGACAG TCAGGAAGTG    420
CAGTATCA                                                             428 
           
           
             
               554 base pairs 
               nucleic acid 
               single 
               linear 
             
             
               DNA (genomic) 
             
             
               unknown 
               dpd2092 lower 
             
             16
AGGCCAATCA GAGTGGCGAT AACCCACACC ACGATGCGCA ACCCGGAGCC AGAAAGCACC     60
GGAACGCCGG CAATCCCCTG AGCAACGACC ACACAAAACG GGTTCATCCA CGAACTGGCA    120
AAACCGATTT GCGTGGCAAT ATAGGTCACC AGGACGGTGG TAATACTGTC ATAGCCCAGC    180
CGGACCATTA GCGGTGCGAT GATAATGGCA AAGGCGACGG CCTCTTCTCC CATACCAAAT    240
ACCGCGCCGC CAAGTGAAAA CAGAATAAAC AGCGCAGGAA TAAAGAGAAT TTCATTCCCG    300
CGGGTATGGC GAATAAGCGC CAGGATACCG TTATCAATGG TTCCTGTACG CATCACAATG    360
CCAAACGCGC CGCCAATCAC CAGCATAAAC ATGATGATGC CAACGGCTGT CCCGTATTTC    420
GATCCTGAAG TTAATCCTTC AAACGGGAAT TCATCAGCCC GGGCGTTCAT CGCCCGTCGT    480
GAACAGCTGT ACGCGGTGAT ACTCAGGTTC CCTGCTTCGT AATCAAATGC AAATGATTTT    540
GATCTACAAT TTGC                                                      554 
           
           
             
               87 base pairs 
               nucleic acid 
               single 
               linear 
             
             
               DNA (genomic) 
             
             
               unknown 
               dpd3501 upper 
             
             17
GGTCACTTAC TAGGTTATCG GGCCGGTGAT GTCCGACCTC ATGGGCGGGC TGCTCCACTT     60
CCTGAATACC ATTCCTCCAT CAATGAA                                         87 
           
           
             
               134 base pairs 
               nucleic acid 
               single 
               linear 
             
             
               DNA (genomic) 
             
             
               unknown 
               dpd3501 lower 
             
             18
ACGACGTCCG GTTTAATGTG TTCCGCCGAG GTTTGCGCCC CGCGTAGCCC AACTTCTTCT     60
TCCACACTGC CAACGCCATA CAGCGTAATT TCGGGATTAT TCACCGTCTG CAATAGTTCA    120
GCCATCATTG CGCA                                                      134 
           
           
             
               203 base pairs 
               nucleic acid 
               single 
               linear 
             
             
               DNA (genomic) 
             
             
               unknown 
               dpd3505 upper 
             
             19
TATGGTTTAT CGCTGGTGGG ATTCGGTCTG TTGATTTCAT CACTCTGTTC AACACAACAG     60
CAGGCGTTTA TCGGCGTGTT TGTCTTTATG ATGCCCGCCA TTCTCCTTTC CGGTTACGTT    120
TCTCCGGTGG AAAACATGCC GGTATGGCTG CAAAACCTGA CGTGGATTAA CCCTATTCGC    180
CACTTTACGG ACATTACCAA GCA                                            203 
           
           
             
               410 base pairs 
               nucleic acid 
               single 
               linear 
             
             
               DNA (genomic) 
             
             
               unknown 
               dpd3505 lower 
             
             20
CTGTCCAGTC GTAGTAGAGG AAATTGCACC GGAAACGTGC GCGCCGGGCG TCCGTGGGCG     60
CGGGTAAAAA TCTCATCCAG TCCGGCCTGC ACTTTTAACG GATGATTAGC TTTTTGCCGC    120
CAGTCATTGA AATCACCCGC CACCAATACC GGTTCGCCGT CCGGTAGCTC ATTCACCCAT    180
TCGGCGAGCA TCGCAAGCTG CGCCTGACGG TGCGCCTCAC GCAGGCCCAG ATGTACGCAC    240
ATCACATGAA TCGCTTTTCC GGTCATCGGC GGCACAATGC GGCAGTAGAG CACGCCGCGC    300
TTTTCCGCAC CATCGACCGA AACATCGCGA TTCTCATAAT GTTCAATGGG ATAACGCGAC    360
AGTACGGCGT TGCCGTGATG CCCTTCCGGG TATACGGCAT TGCGACCGTA               410 
           
           
             
               164 base pairs 
               nucleic acid 
               single 
               linear 
             
             
               DNA (genomic) 
             
             
               unknown 
               dpd3507 upper 
             
             21
GCCGTTACAC ACGCTGCCAC TGGCAACCAA AGTCCCGGAA CCCTTACCGC CGCTGGAAGG     60
ATACACCTTT GAGGGCTACG CAATGCCGAT GGCAGCGTGG GCACCAAAAA CCTGCTCGGT    120
ATCACCACCA GCGTCCACTG TGTGGCAGGC GTGGTGGACT ATGT                     164 
           
           
             
               285 base pairs 
               nucleic acid 
               single 
               linear 
             
             
               DNA (genomic) 
             
             
               unknown 
               dpd3507 lower 
             
             22
CTCCTGTTCA TCTCCCAGTC GGCACATAAA TACTTGCCCA CCAGGCAGAA TTTCGTAATG     60
AATGCTGTCC TGGCCTGGCT TCAGTTTTAA GGCCTCACGC ACTGGCGCGG GGATAGTTGT    120
TTGTCCGCGT ATCGTGACCT TTGATTCAGT GGTCAGTACA GCGTGAGAGC GAGCATTAGC    180
GGGCATGATT CACTGTCCTT TTACAGCCTG TTTTCTGCTC AAATTATAAG CTTGAACTAA    240
GGTAATGCAA ATGCATTATT AATGGACGTG GGGGCTTTAA ACAAT                    285 
           
           
             
               223 base pairs 
               nucleic acid 
               single 
               linear 
             
             
               DNA (genomic) 
             
             
               unknown 
               dpd3509 upper 
             
             23
GATGGAGTGG CGTAACTATC CGGTAACGCT GGTGGCAGAA AATAACGTTA CCGAAGGCTT     60
TATCGCTGGT CGTCTCACTC GCGAACTGCT GGCAGGTGTA CCTGACTTAG CTTCACGTAC    120
CGTGATGACC TGCGGCCCGG CTCCGTATAT GGATTGGGTA GAGCAGGAAG TGAAAGCGCT    180
CGGCGTGACG CGTTTCTTTA AAGAGAAATT CTTCACCCCA GTA                      223 
           
           
             
               260 base pairs 
               nucleic acid 
               single 
               linear 
             
             
               DNA (genomic) 
             
             
               unknown 
               dpd3509 lower 
             
             24
TGCTCCGGGC TGGAAACCAG CTCGCAATAG TGACTACATT CGCGGAATAG CTCTTGTGGG     60
TGGGTTTCCT GGAAATAGCC GCTGCCAATT TCGCTGGAGG GAATATGAGC GGCAATCGCC    120
AGTACCGGAA CGTGATTGCG GTGGCAATCG AACAGGCCGT TGATTAAGTG CAGGTTGCCG    180
GGGCCGCACG ATCCGGCGCA GACCGCCAGT TCTCCGCTAA GTTGTGCTTC AGCGCCAGCG    240
GCAAAGGCCG CCACTTCTTC                                                260 
           
           
             
               172 base pairs 
               nucleic acid 
               single 
               linear 
             
             
               DNA (genomic) 
             
             
               unknown 
               dpd3512 upper 
             
             25
AATGGAGTTT GACTAATACA GGAATACTAT GAGTCTGAAT TTCCTTGATT TTGAACAGCC     60
GATTGCAGAG CTGGAAGCGA AAATCGATTC TCTGACTGCG GTTAGCCGTC AGGATGAGAA    120
ACTGGATATT AACATCGATG AAGAAGTGCA TCGTCTGCGT GAAAAAAGCG TA            172 
           
           
             
               527 base pairs 
               nucleic acid 
               single 
               linear 
             
             
               DNA (genomic) 
             
             
               unknown 
               dpd3512 lower 
             
             26
ACTTTTCCCG CAACACGCTC GCCGCTCATA CCACTTTTAC CCTGGTAGAT CGGATGAAAA     60
TGGGTGTACG GCACCCAGGC AGAATCGAAG TGAATCGACG GGACATCCAG CGTCTGTTTG    120
ATCCAGTCGG TGTTGTAGAG CAAGCCATCA TAGGTGGAGT TGGTGATCAC CGCATGAACC    180
GGCCATTGTG CTTGCGTGGT AGCAGCGACT TTCTCTTCGA TGCTGTCGCG AGTAAATTCA    240
CGGCGCGGGA TCCCACCAAG AATCCCCAAC GCATTACGCG TCGGTTTCAG CCAGACTGGC    300
ACTACATCGT TCATCATCAA CAGATGCGCC AGCGATTTAT GACAATTGCG GTCGATCAAC    360
AGCGTACTGC CGGATGGCGC GGCGTACATA CCCACAATTT TGTTCGACGT CGATGTTCCG    420
TTGGTAACGA TATAACTCTG TTCCGCCCAA AATCCCGCGA TTACTCTTCC GCTTCCAGTG    480
TTGCCCGTGT TGTCAACAAC AACAACTCGG TGACCGAAAT AAAACTC                  527 
           
           
             
               20 base pairs 
               nucleic acid 
               single 
               linear 
             
             
               DNA (genomic) 
             
             
               unknown 
               upper primer 
             
             27
GGATCGGAAT TCCCGGGGAT                                                 20 
           
           
             
               20 base pairs 
               nucleic acid 
               single 
               linear 
             
             
               DNA (genomic) 
             
             
               unknown 
               lower primer 
             
             28
CTGGCCGTTA ATAATGAATG                                                 20