bluuebunny/crossref_metadata_2025 huggingface dataset:
Mu-lac insertion-directed mutagenesis in a pectate lyase gene of Erwinia chrysanthemi
Authors: Diolez A , Coleno A
Published: January 2020

The pelC gene, which encodes one of the five major pectate lyase (PL) isoenzymes in Erwinia chrysanthemi 3937, designated PLc, was subcloned from a hybrid lambda phage into a pBR322 derivative and mutagenized with a mini-Mu-lacZ transposable element able to form fusions to the lacZ gene. One plasmid (pAD1) which had an inactivated pelC gene and a Lac+ phenotype was selected in Escherichia coli. This plasmid was introduced into Erwinia chrysanthemi, and the pelC::mini-Mu insertion was substituted for the chromosomal allele by homologous recombination. This strain lacks the PLc isoenzyme. This Erwinia chrysanthemi strain has a Lac+ phenotype that is inducible by polygalacturonate, as are the wild-type PL activities.
Analysis of the ruv locus of Escherichia coli K-12 and identification of the gene product
Authors: Attfield P V , Benson F E , Lloyd R G
Published: January 2020

The ruv gene of Escherichia coli, which is associated with inducible mechanisms of DNA repair and recombination, has been cloned into the low-copy plasmid vector pHSG415. The recombinant plasmid pPVA101 fully complements the DNA repair-deficient phenotype of ruv mutants. Restriction endonuclease analysis of this plasmid revealed a 10.6-kilobase (kb) HindIII DNA insert which contained a 7.7-kb PstI fragment identified as being from the chromosomal ruv region. Deletion analysis and Tn1000 insertional inactivation of ruv function located the ruv coding region to a 2.2-kb section of the cloned DNA fragment. A comparison of the proteins encoded by ruv wild-type and mutant plasmids identified the gene product as a protein of molecular weight 41,000.
Selection and properties of phototaxis-deficient mutants of Halobacterium halobium
Authors: Sundberg S A , Bogomolni R A , Spudich J L
Published: January 2020

A method for isolating phototaxis-deficient (Pho-) mutants of Halobacterium halobium was developed. The procedure makes use of a flashing repellent light to induce frequent reversals of swimming direction by responsive cells, thereby impeding their migration along a small capillary and resulting in a spatial separation of the parent population and a population enriched for Pho- cells. Two classes of Pho- mutants were obtained by this selection scheme: those which have lost the chemotactic response (Che-) as well as phototaxis sensitivity (general taxis mutants), and those which are defective in steps specific to phototaxis (photosignaling mutants). In the latter class, several retinal synthesis mutants were isolated, as well as a strain which fit the expected properties of a mutant lacking a functional photoreceptor protein. On the basis of spectroscopic and swimming behavior studies, the retinal-containing protein, slow-cycling or sensory rhodopsin (SR), was previously proposed to be a dual-function sensory receptor mediating both attractant and repellent photosensing. The receptor mutant Pho81 fulfills two predictions which provide direct genetic evidence for this proposal. The mutant has lost SR photoactivity as determined by spectroscopic measurements, and it has simultaneously lost both attractant and repellent phototaxis sensitivity. Comparison of [3H]retinal-labeled membrane proteins from the mutant and its SR-containing parent implicated a 25,000 Mr polypeptide as the chromophoric polypeptide of SR.
Trypsinlike enzymes from dormant and germinated spores of Bacillus cereus T and their possible involvement in germination
Authors: Boschwitz H , Halvorson H O , Keynan A , Milner Y
Published: January 2020

Trypsin-like enzymes were studied in dormant, activated, and germinated spores of Bacillus cereus T. Dormant spores contained two heat-labile enzyme activities. One was extractable with 2 M KCl and hydrolyzed azo-albumin. The second, a trypsinlike activity, was not extractable with 2 M KCl and hydrolyzed benzoyl-L-arginine-p-nitroanilide. Because of their heat instability, these two enzyme activities are probably not involved in the germination of heat-activated spores. Upon germination of heat-treated spores, a trypsinlike protease which was not detected in intact dormant spores was activated or exposed. This enzyme, when measured in intact germinated spores, hydrolyzed benzoyl-DL-arginine-p-nitroanilide but not azo-albumin and was inhibited in situ by sulfhydryl-blocking reagents such as p-chloromercuribenzoic acid and Hg2+. There was a correlation between the inhibition of germination and enzymatic activity by sulfhydryl-blocking reagents. The enzyme was also inhibited by leupeptin, tosyl-L-lysine chromoethyl ketone, and tosyl-L-arginine methyl ester. Good correlation existed between the inhibition of germination and enzymatic activity by these agents. Electron micrographs showed that in the presence of trypsin inhibitors, the spores did not lose their cortex. The protein extracts of the inhibited spores formed a somewhat different electrophoretic pattern in sodium dodecyl sulfate-polyacrylamide gel electrophoresis than the protein extracts of dormant or germinated spores.
Effects of a mutation that eliminates UDP glucose-pyrophosphorylase on the pathogenicity of Erwinia carotovora subsp. carotovora
Authors: Jayaswal R K , Bressan R A , Handa A K
Published: January 2020

A nonpathogenic mutant of Erwinia carotovora obtained by Mu d1 mutagenesis was defective in the ability to utilize several carbon sources. The basis of the mutation was analyzed biochemically and shown to be a defect in the ability to form UDP glucose-pyrophosphorylase. The nonpathogenic phenotype of the mutant was caused by its sensitivity to galactose.
Bacteriophage receptor area of outer membrane protein OmpA of Escherichia coli K-12
Authors: Morona R , Krämer C , Henning U
Published: January 2020

A number of T-even-like bacteriophages use the outer membrane protein OmpA of Escherichia coli as a receptor. We had previously analyzed a series of ompA mutants which are resistant to such phages and which still produce the OmpA protein (R. Morona, M. Klose, and U. Henning, J. Bacteriol. 159:570-578, 1984). Mutational alterations were found near or at residues 70, 110 and 154. Based on these and other results a model was proposed showing the amino-terminal half of the 325-residue protein crossing the outer membrane repeatedly and being cell surface exposed near residues 25, 70, 110, and 154. We characterized, by DNA sequence analysis, an additional 14 independently isolated phage-resistant ompA mutants which still synthesize the protein. Six of the mutants had alterations identical to the ones described before. The other eight mutants possessed seven new alterations: Ile-24----Asn, Gly-28----Val, deletion of Glu-68, Gly-70----Cys, Ser-108----Phe, Ser-108----Pro, and Gly-154----Asp (two isolates). Only the latter alteration resulted in a conjugation-deficient phenotype. The substitutions at Ile-24 and Gly-28 confirmed the expectation that this area of the protein also participates in its phage receptor region. It is unlikely that still other such sites of the protein are involved in the binding of phage, and it appears that the phage receptor area of the protein has now been characterized completely.
High levels of glycolipid and low levels of phospholipid in a marine caulobacter
Authors: De Siervo A J
Published: January 2020

Studies of the lipid composition of the marine bacterium Caulobacter halobacteroides revealed the presence of glycolipid as the predominant lipid constituent. The presence of minor amounts of phospholipid was confirmed with the incorporation of 14C- and 32P-labeled compounds. Other marine caulobacters had similar lipid compositions. Five chromatographically separable glycolipids were detected, two of which were identified as mono- and diglycosyldiglycerides. Glycolipid constituted 90 to 99% of the total extractable lipid based on 14C-acetate incorporation into six marine caulobacter strains. In addition, comparisons were made with the lipid extracts of the nonmarine Caulobacter crescentus and Micrococcus lysodeikticus, which contain substantial amounts of phospholipid. Studies of lipid composition during growth showed the maximum amount of phospholipid during early logarithmic growth (2.9%) with a decrease to 0.3% in the early stationary phase. The finding of a group of organisms in which phospholipid is not a major constituent of the lipid fraction is unique and generates many questions about the lipid requirements for membrane structure and function.
Escherichia coli rep gene: identification of the promoter and N terminus of the rep protein
Authors: Bialkowska-Hobrzanska H , Gilchrist C A , Denhardt D T
Published: January 2020

The functional Escherichia coli rep gene, which encodes the Mr 67,000 Rep helicase, has been localized within a 2.55-kilobase sequence. Its regulatory region has been characterized by the use of rep-lacZ fusions. The direction of transcription of the rep gene is clockwise on the E. coli chromosome, as are the nearby ilvC and rho genes. The sequence of the rep control region was determined, and putative regulatory sequences were identified; no evidence for autoregulation of expression was obtained. Transcription of the gene was not enhanced during the SOS response. The location of the promoter and the beginning of the protein were confirmed by S1 nuclease mapping of the 5' end of rep mRNA and determination of the NH2-terminal sequence of the rep protein.
Genetic organization and transcription from the gene (trmA) responsible for synthesis of tRNA (uracil-5)-methyltransferase by Escherichia coli
Authors: Lindström P H , Stüber D , Björk G R
Published: January 2020

The enzyme catalyzing the formation of 5-methyluridine (ribothymidine) in tRNA of Escherichia coli is tRNA (uracil-5)-methyltransferase (EC 2.1.1.35). A 2.8-kilobase EcoRI chromosomal DNA fragment contains trmA, the structural gene for this enzyme. Subcloning, transcription in vitro, Tn5 insertion mutagenesis, and transcriptional fusion experiments were performed to establish the gene organization of the trmA region on the E. coli chromosome. trmA is a monocistronic operon. The trmA promoter was localized by in vitro experiments, and the direction of transcription was shown to be counterclockwise on the standard E. coli K-12 chromosomal map. The level of transcription of trmA in vitro and the expression of protein in minicells equal those of the bla gene of plasmid pBR322.
Insertional mutagenesis of the lon gene in Escherichia coli: lon is dispensable
Authors: Maurizi M R , Trisler P , Gottesman S
Published: January 2020

The lon gene of Escherichia coli codes for an ATP-dependent protease. Mutations in lon cause a defect in the intracellular degradation of abnormal and mutant proteins and lead to a number of phenotypic changes, such as UV sensitivity and overproduction of capsular polysaccharide. We have isolated lambda transducing phage carrying the lon gene and used the lon phage as a target for insertional mutagenesis by a defective transposon Tn10 to produce lon::delta 16 delta 17Tn10 derivatives. The delta 16 delta 17Tn10 (hereafter called delta Tn10) elements were inserted at sites throughout the lon gene and disrupted the coding region between 15 and 75% of the distance from the amino-terminal end. Radioactive labeling of proteins in vivo in cells infected with different lambda lon::delta Tn10 phage demonstrated that the insertions resulted in the synthesis of truncated Lon proteins. The lon::delta Tn10 mutations, when crossed from the phage into the bacterial chromosome, abolished the synthesis of intact Lon protein, as assayed by antibody on Western blots. An analysis of the protein-degradative ability of lon::delta Tn10 cells suggests that although the insertions in lon caused a reduction in ATP-dependent protein degradation, they did not completely eliminate such degradation either in vivo or in vitro. The lon::delta Tn10 mutations and a lon deletion retaining only the amino-terminal 25% of the gene did not affect the energy-dependent degradation of proteins during starvation and led to only a 40 to 60% reduction in the ATP-dependent degradation of canavanine-containing proteins and puromycyl peptides. Our data provide clear evidence that energy-dependent proteolytic enzymes other than Lon exist in E. coli.
Scanning electron microscope study of Pseudomonas putida colonies
Authors: Shapiro J A
Published: January 2020

Pseudomonas putida colonies were examined by scanning electron microscope. A variety of cell morphologies, multicellular arrangements, and extracellular materials were observed in the fixed material. Different regions of a single colony showed characteristic organizations of these architectural elements. In some cases, the detailed microstructure of the fixed colony surfaces observed by scanning electron microscopy could be correlated with macroscopic patterns visualized by histochemical staining and surface relief photography of live colonies. Extracellular materials were seen to extend onto the agar surface beyond the boundaries of the cell mass, and the final structures of these materials, after fixation and desiccation, were colony specific. The significance of these features of colony microstructure for formulating hypotheses about the control of colony morphogenesis is discussed.
Salmonella typhimurium proP gene encodes a transport system for the osmoprotectant betaine
Authors: Cairney J , Booth I R , Higgins C F
Published: January 2020

Betaine (N,N,N-trimethylglycine) can be accumulated to high intracellular concentrations and serves an important osmoprotective function in enteric bacteria. We found that the proP gene of Salmonella typhimurium, originally identified as encoding a minor transport system for proline (permease PP-II), plays an important role in betaine uptake. Mutations in proP reduced the ability of betaine to serve as an osmoprotectant. Transport of betaine into the cells was also severely impaired in these mutants. The kinetics of uptake via PP-II suggest that betaine, rather than proline, is the important physiological substrate for this transport system. Betaine uptake via PP-II was regulated by osmotic pressure at two different levels: transcription of the proP gene was increased by increasing osmolarity, and, in addition, activity of the transport system itself was dependent upon the osmotic pressure of the medium. The specificity of the transport system was also altered by increasing osmolarity which enhanced the affinity for betaine while reducing that for proline.
Cloning and DNA sequence of a plasmid-determined citrate utilization system in Escherichia coli
Authors: Sasatsu M , Misra T K , Chu L , Laddaga R , Silver S
Published: January 2020

The citrate utilization determinant from a large 200-kilobase (kb) naturally occurring plasmid was previously cloned into the PstI site of plasmid vector pBR325 creating the Cit+ tetracycline resistance plasmid pWR61 (15 kb). Tn5 insertion mutagenesis analysis of plasmid pWR61 limited the segment responsible for citrate utilization to a 4.8-kb region bordered by EcoRI and PstI restriction nuclease sites. The 4.8-kb fragment was cloned into phage M13, and the DNA sequence was determined by the dideoxyribonucleotide method. Within this sequence was a 1,296-base-pair open reading frame with a preceding ribosomal binding site. The 431-amino-acid polypeptide that could be translated from this open reading frame would be highly hydrophobic. A second long open reading frame with the potential of encoding a 379-amino-acid polypeptide preceded the larger open reading frame. Portions of the 4.8-kb fragment were further subcloned with restriction endonucleases BglII and BamHI, reducing the minimum size needed for a citrate-positive phenotype to a 1.9-kb BamHI-BglII fragment (which includes the coding region for the 431-amino-acid polypeptide, but only the distal 2/3 of the reading frame for the 379-amino-acid polypeptide). Citrate utilization results from a citrate transport activity encoded by the plasmid. With the 4.8-kb fragment (as with larger fragments) the citrate transport activity was inducible by growth on citrate. On transfer from glucose, succinate, malate, or glycerol medium to citrate medium, the Cit+ Escherichia coli strains showed a delay of 36 to 48 h before growth.
dfp Gene of Escherichia coli K-12, a locus affecting DNA synthesis, codes for a flavoprotein
Authors: Spitzer E D , Weiss B
Published: January 2020

The cloned dfp gene complements dna-707 (now designated dfp-707), a temperature-sensitive conditionally lethal mutation that results in a slow cessation of DNA synthesis while protein synthesis is maintained. In vitro and in vivo experiments failed to demonstrate a specific defect in the initiation of DNA replication, and turn-off of DNA synthesis at high temperature was slower than that of a typical initiation (dnaA) mutant. The gene was localized, and its product was identified through the construction and analysis of deletion and insertion mutants of dfp-containing plasmids. dfp is located between the rpmB and dut genes at 81 min on the linkage map of Escherichia coli K-12. It is transcribed clockwise, independently of dut. The ability of a plasmid to complement a chromosomal dfp-707 mutation was correlated with its ability to produce a 45-kilodalton polypeptide. The purified protein contained 1 mol of flavin mononucleotide per mol of polypeptide.
SUSCEPTIBILITY OF SUCKLING MICE TO VARIOLA VIRUS
Authors: Marshall Ronald G. , Gerone Peter J.
Published: January 2020

Marshall, Ronald
G. (Army Chemical Corps, Fredrick, Md.),
and Peter J. Gerone
. Susceptibility of suckling mice to variola virus. J. Bacteriol.
82:
15–19. 1961.—The susceptibility of suckling mice inoculated intraperitoneally or intracerebrally with variola virus was investigated. Data are presented that define the death patterns, the relationship of incubation period to dose of virus inoculated, the multiplication of virus in suckling mice, and the influence of the age of suckling mice on their susceptibility to this virus. Additionally the results indicate that a variola virus neutralization test is feasible using the young suckling mouse as an indicator host.
AMINO ACID INTERACTIONS IN
NEUROSPORA CRASSA
Authors: Soboren Josephine , Nyc Joseph F.
Published: January 2020

Soboren, Josephine
(University of California, Los Angeles),
and Joseph F. Nyc
. Amino acid interactions in
Neurospora crassa
. J. Bacteriol.
82:
20–25. 1961.—A systematic study of the effects of the naturally occurring amino acids on the growth of a wild-type strain of
Neurospora crassa
focused attention upon
l
-tryptophan, which exhibits a strong growth inhibitory effect. Further investigation disclosed that other tryptophan metabolites, anthranilic acid, indole, kynurenine, and 3-hydroxykynurenine also inhibit growth. The proposed antimetabolic role of these aromatic compounds explains the poor growth response of certain tryptophan-requiring strains of
N. crassa
to tryptophan supplements. The growth of normal and mutant strains of
N. crassa
on media supplemented with tryptophan is influenced by the presence of other amino acids.
VIRULENCE AND CITRULLINE UREIDASE ACTIVITY OF
PASTEURELLA TULARENSIS
Authors: Marchette Nyven J. , Nicholes Paul S.
Published: January 2020

Marchette, Nyven
J. (University of Utah, Salt Lake City),
and Paul S. Nicholes
. Virulence and citrulline ureidase activity of
Pasteurella tularensis
. J. Bacteriol.
82:
26–32. 1961.—The presence of a citrulline ureidase system in
Pasteurella tularensis
strains of high virulence, and its absence in avirulent strains and strains of low virulence was confirmed. The presence of this system, however, was shown to be not directly related to virulence.

The only wild strain of
P. tularensis
tested that lacked a citrulline ureidase system was isolated from a rodent. All the strains, isolated from rabbits, rabbit ticks, a human being, and a horse, that were tested possessed this system.

The existence of two North American varieties of
P. tularensis
was postulated on the basis of virulence and citrulline ureidase activity.
ASSAY OF POLY-β-HYDROXYBUTYRIC ACID
Authors: Law John H. , Slepecky Ralph A.
Published: January 2020

Law, John
H. (Harvard University, Cambridge, Mass.)
and Ralph A. Splepecky
. Assay of poly-β-hydroxybutyric acid. J. Bacteriol.
82:
33–36. 1961—A convenient spectrophotometric assay of bacterial poly-β-hydroxybutyric acid has been devised. Quantitative conversion of poly-β-hydroxybutyric acid to crotonic acid by heating in concentrated sulfuric acid and determination of the ultraviolet absorption of the produce permits an accurate determination of this material in quantities down to 5 μg. This method has been used to follow the production of poly-β-hydroxybutyric acid by
Bacillus megaterium
strain KM.
INHIBITION OF ALGAE BY NYSTATIN
Authors: Lampen J. O. , Arnow Peter
Published: January 2020

Lampen
, J. O. (Rutgers, the State University, New Brunswick, N. J.),
and Peter Arnow
. Inhibition of algae by nystatin. J. Bacteriol.
82:
247–251. 1961.—The polyenic antibiotic nystatin inhibited the growth of a broad range of algae at concentrations of 1 to 30 μg per ml. Organisms included in the Chlorophyta, Euglenophyta, Chrysophyta, and Cyanophyta were inhibited, but a Bacillariophyceae was insensitive. Nystatin was lethal at concentrations which completely prevented growth. The polyene was absorbed by sensitive algae from aqueous medium. Nystatin produced K
+
leakage, but did not inhibit dark respiration or photosynthetic oxygen production. The effects of the antibiotic on algae appear to be similar in many ways to those on yeast.
PHYLOGENY OF PHOSPHOMANNAN-PRODUCING YEASTS I.
The Genera
Authors: Wickerham Lynferd J. , Burton Kermit A.
Published: January 2020

Wickerham, Lynferd
J. (U. S. Department of Agriculture, Peoria, Ill.),
and Kermit A. Burton
. Phylogeny of phosphomannan-producing yeasts. I. The genera. J. Bacteriol.
82:
265–268. 1961.—Primitive yeasts of the genera
Hansenula, Pichia
, and
Pachysolen
produce extracellular phosphorylated mannans. The phosphomannans cause adherence of the cells to bark beetles that transport the yeasts from the sap-conducting tissues of one tree to another. Two yeasts that produce phosphomannans most abundantly are the most primitive species of
Hansenula
;
H. holstii
is heterothallic, and
H. capsulata
is homothallic. From these two species issued lines of species developing toward independence from trees as their habitat and other lines that developed toward greater dependence upon trees. Most of the primitive species of
Pichia
are very similar to those species of
Hansenula
that are highly dependent upon trees. The one available species of
Pachysolen
resembles species of the less dependent lines.
FATTY ACID METABOLISM IN
SERRATIA MARCESCENS
I
Authors: Bishop D. G. , Still J. L.
Published: January 2020

Bishop
, D. G. (University of Sydney, Sydney, Australia),
and J. L. Still
. Fatty acid metabolism in
Serratia marcescens
. J. Bacteriol.
82:
370–375. 1961.—A study has been made of the oxidation of saturated fatty acids containing between two and 18 carbon atoms by whole cells of the bacterium,
Serratia marcescens
. This organism was found to be capable of oxidizing all of the acids tested, but variations in the rate and total oxygen uptake were found. These variations were dependent on the length of the carbon chain in the substrate molecule and the pH of the reaction mixture. The concept that these variations are due to a cellular permeability barrier to the substrate is discussed.
ENZYMATIC EXPRESSION OF GENETIC UNITS OF FUNCTION CONCERNED WITH GALACTOSE METABOLISM IN
ESCHERICHIA COLI
Authors: Soffer Richard L.
Published: January 2020

Soffer, Richard
L. (Stanford University, Palo Alto, Calif.). Enzymatic expression of genetic units of function concerned with galactose metabolism in
Escherichia coli
. J. Bacteriol.
82:
471–478. 1961.—A series of genetically characterized galactose-negative mutants of
Escherichia coli
strain K12 were studied with respect to the enzymes of the Leloir pathway for utilization of this sugar. The functions pertaining to the three genetically defined cistrons were found to relate, respectively, to the expression of galactokinase, galactose 1-phosphate uridyl transferase, and uridine diphosphate galactose 4-epimerase. Mutants defective in the latter enzyme represent a new biochemical class in this strain of
E. coli
. Most of the mutants defective in galactokinase were found to exhibit significantly elevated levels of galactose 1-phosphate uridyl transferase as compared with the wild type when grown under conditions of induction. A suppressed transferase-deficient mutant was found to have regained this enzymatic activity.
FERMENTATION REACTIONS OF
ERYSIPELOTHRIX RHUSIOPATHIAE
Authors: White Thomas G. , Shuman Richard D.
Published: January 2020

White, Thomas
G. (U. S. Department of Agriculture, Ames, Iowa),
and Richard D. Shuman
. Fermentation reactions of
Erysipelothrix rhusiopathiae
. J. Bacteriol.
82:
595–599. 1961.—A study was made to determine the effect of four different basal media, to which fermentable carbon compounds had been added, upon 22 selected strains of
Erysipelothrix rhusiopathiae
(
insidiosa
). Acid production was measured by (i) chemical indicator, (ii) change in pH, and (iii) production of titrable acidity. At least two determinations, usually four, were made for each test on each strain.

The fermentation pattern varied according to the medium, the indicator, and the method of measuring acid production. Andrade's base plus serum was the most dependable medium because it permitted the least variation in the total number of different patterns. Of the three methods used to measure acid production, the chemical indicator gave the most valid and reproducible results.

The within-strain variation was not extreme and most strains persisted in a given fermentation pattern under like conditions of growth and acid production. Results of the study indicated that, regardless of the medium and indicator routinely used, one should be familiar with the fermentation pattern of known strains of the erysipelas organism.
ROLE OF VALINE AND ISOLEUCINE AS REGULATORS OF ACTINOMYCIN PEPTIDE FORMATION BY
STREPTOMYCES CHRYSOMALLUS
Authors: Katz Edward , Waldron Clarence R. , Meloni Mary Lou
Published: January 2020

Katz, Edward
(Rutgers, The State University, New Brunswick, N. J.),
Clarence R. Waldron, and Mary Lou Meloni
. Role of valine and isoleucine as regulators of actinomycin peptide formation by
Streptomyces chrysomallus
. J. Bacteriol.
82:
600–608. 1961—
d
-Valine is an effective inhibitor of actinomycin synthesis by
Streptomyces chrysomallus
;
l
-valine stimulates actinomycin production and reverses the inhibition due to the
d
-enantiomorph. The incorporation of
l
-valine into the medium results, particularly, in a marked increase in actinomycin IV formation. In studies with various isoleucine isomers it was shown that
l
-isoleucine enhances actinomycin VII production; the principal effect of
d
-alloisoleucine and, especially,
d
-isoleucine, is to bring about synthesis of two new actinomycins which contain
N
-methylisoleucine. Both
l
- and
d
-threonine were observed to have an effect similar to that obtained with
l
-isoleucine. An interpretation of these findings has been discussed.
UNUSUAL RIBOSOME PARTICLES OCCURRING DURING SPORE GERMINATION
Authors: Woese Carl R.
Published: January 2020

Woese, Carl
R. (Yale University, New Haven, Conn.). Unusual ribosome particles occurring during spore germination. J. Bacteriol.
82:
695–701. 1961.—Spores of
Bacillus subtilis
germinated for varying amounts of time were disrupted under conditions of varying divalent ion concentration and analyzed for content of ribosomes by ultracentrifugal techniques. The picture of microsome development during germination is as follows: The spore contains only 50S and 68S particles. Early in germination, 25S and 35-8S particles increase in amount first. These particles seem to be formed in close association with the cell deoxyribonucleic acid. Their binding in the cell requires a chelating agent to release them maximally. Further, 25S and 35-8S particles are the only ones sensitive to ribonuclease and the only ones produced in the presence of chloramphenicol. The kinetics of their appearance, and their relative size, suggest them as precursors of 50S particles, which increase in amount shortly after appearance of 25S and 35S particles. It was found that 31S particles do not appear until later in germination, and their appearance signals a rise in 68S material, suggesting again the oft-reported relationship: one 31S + one 50S = one 68S. We have been unable to discern any precursors of the 31S material in these studies.
PERMEABILITY OF BACTERIAL SPORES II
Authors: Gerhardt Philipp , Black S. H.
Published: January 2020

Gerhardt, Philipp
(University of Michigan, Ann Arbor)
and S. H. Black
. Permeability of bacterial spores. II. Molecular variables affecting solute permeation. J. Bacteriol.
82:
750–760. 1961.—More than 100 compounds were tested for their uptake by dormant spores of a bacillus. The extent of penetration was found to be dependent on at least three molecular properties: (i) The dissociation of electrolytes usually resulted in high or low uptake predictable from their charge. (ii) Lipid insolubility restricted permeation of small molecules. (iii) The molecular weight of unsubstituted glycol and sugar polymers exponentially limited penetration to eventual exclusion at mol wt above 160,000. The results were plotted as a generalized curve, calculations from which permitted an interpretation that the effective spore surface contains pores varying in diameter from 10 to 200 A.
SIALIC ACIDS (N,7-O-DIACETYLNEURAMINIC ACID ANDN-ACETYLNEURAMINIC ACID) INESCHERICHIA COLII
Authors: Dewitt Charles W. , Rowe Janet A.
Published: January 2020

DeWitt, CharlesW. (The Upjohn Co., Kalamazoo, Mich.)and Janet A. Rowe. Sialic acids (N,7-O-diacetylneuraminic acid andN-acetylneuraminic acid) inEscherichia coli. I. Isolation and identification. J. Bacteriol.82:838–848. 1961.—Two sialic acids,N-acetylneuraminic acid andN,7-O-diacetylneuraminic acid, were obtained in crude mixtures from whole cells ofEscherichia coliand from its endotoxin by weak acid hydrolysis followed by anion exchange resin chromatography. Yields from whole cells were 0.1 to 0.2% (dry weight) with 50 to 60% purity. Identification of the sialic acids was by comparative paper chromatography and colorimetric assays using the acidicp-dimethylaminobenzaldehyde (direct Ehrlich), resorcinol and thiobarbituric acid reactions. TheN-acetyl derivative was also shown to be susceptible to hydrolysis by clostridialN-acetylneuraminic aldolase and the end products identified,N-acetylamannosamine by paper chromatography and pyruvic acid by oxidation of DPNH with lactic acid dehydrogenase. The two sialic acids were separated on paper chromatograms, eluted, and assays for total and ester acyl groups showed the suspectedN-acetyl derivative to contain 0.11 O-acyl and 1.16N-acetyl groups per mole sialic acid and the diacetyl derivative to have 1.10 O-acyl and 0.93N-acetyl groups per mole. The O-acyl group was identified as acetyl by preparation of the hydroxamate.
CELL MULTIPLICATION STUDIED WITH AN ELECTRONIC PARTICLE COUNTER
Authors: Toennies G. , Iszard L. , Rogers N. B. , Shockman G. D.
Published: January 2020

Toennies
, G. (Institute for Cancer Research, Philadelphia, Pa.), L.
Iszard, N. B. Rogers, and G. D. Shockman
. Cell multiplication studied with an electronic particle counter. J. Bacteriol.
82:
857–866. 1961.—Suitable conditions are described for the application of the Counter electronic particle counter to the study of bacterial number and particle size distribution in growing cultures. When
Streptococcus faecalis
and
Escherichia coli
were each grown in a different medium, exponential growth was accompanied by a continuous decrease in average particle size. The average apparent particle volume of
S. faecalis
decreased by about 50% in five generations. Microscopic studies of
S. faecalis
indicated that this was due to a decrease in the average chain length of the cultures. The following observations concerning average particle size during exponential growth of
S. faecalis
in a synthetic medium were made: (i) A decreased concentration of tryptophan, serine, or proline resulted in a significant decrease in average particle size. Similar changes in numerous other nutrients produced no or only minor changes. (ii) The addition of a cytoplasmic extract prepared from exponentially growing cells resulted in changes similar to those resulting from the partial withdrawal from the medium of certain nutrients. (iii) The effect of the cytoplasmic extract could be counteracted by the addition of tryptophan. (iv) A limited survey, including the effects of the rate of exponential growth, mechanical agitation, the presence of indoleacetic acid, indole, kinetin, lysozyme, or ascorbate, disclosed no additional factor which significantly influenced the particle size distribution.
INDUCTION AND REPRESSION OF NITRATE REDUCTASE IN
NEUROSPORA CRASSA
Authors: Kinsky Stephen C.
Published: January 2020

Kinsky, Stephen
C. (Washington University, St. Louis, Mo.). Induction and repression of nitrate reductase in
Neurospora crassa
. J. Bacteriol.
82:
898–904. 1961.—Techniques are described for studying induced enzyme formation in
Neurospora crassa
. The effects of various parameters (time, pH, nitrate concentration, etc.) on the induction of nitrate reductase were investigated. It was demonstrated that NH
4
+
, which is the end product of the metabolic sequence initiated by nitrate reductase, repressed formation of the enzyme. Parallel to the formation of nitrate reductase there was an increase in reduced triphosphopyridine nucleotide (TPNH)-cytochrome
c
reductase activity. The relationship of these two activities to each other and to the constitutive TPNH-cytochrome
c
reductase present in noninduced mycelia is discussed.
LYSOGENY IN STAPHYLOCOCCI
Authors: Blair John E. , Carr Miriam
Published: January 2020

Blair, John
E. (Hospital for Joint Diseases, New York, N. Y.)
and Miriam Carr
. Lysogeny in staphylococci. J. Bacteriol.
82:
984–993. 1961.—Changes in the phage typing patterns of strains of staphylococci of the 80/81-52/52A/80/81 complex and of phage group III were produced by lysogenization with temperate phages derived from selected strains of
Staphylococcus aureus
. The phages used were of the serological groups A, B, and F. Certain changes of phage pattern were related to serologically specific prophage immunity; others were nonspecific, or resulted from the conversion of a strain from partial resistance to full sensitivity to certain typing phages. In addition to an alteration of their phage typing pattern, the lysogenization of certain strains by appropriate phages effected a reversal of their susceptibility to penicillin. The capacity to produce toxin was conferred upon certain nontoxigenic strains by lysogenization with a phage derived from a toxigenic strain.
CYTOLOGY OFRHODOTORULA GLUTINIS
Authors: Thyagarajan T. R. , Naylor H. B.
Published: January 2020

Thyagarajan, T. R. (Cornell University, Ithaca, N. Y.)and H. B. Naylor. Cytology ofRhodotorula glutinis. J. Bacteriol.83:127–136. 1962.—The structure and manner of division of nuclei in actively dividing cells ofRhodotorula glutiniswere studied with the phase contrast microscope. The nucleus consists of a dense central body, surrounded by a shell of optically uniform material of low density. The entire structure is enclosed within a nuclear membrane. Various fixation and staining techniques were employed to confirm the observations made from living cells. Since the dense central body is Feulgen-negative and is readily stained by iron alum hematoxylin, it is identified as the nucleolus. The material surrounding the nucleolus has no marked affinity for hematoxylin but is Feulgen-positive and stains intensely with Giemsa and basic fuchsin. The nucleus appears to divide by a process of elongation and constriction during which roughly half of the nucleolus, along with the surrounding chromatin, passes into the bud. The nuclear membrane was found to persist during all stages of division. Vacuoles were seldom observed in actively dividing cells. The nucleus ofR. glutinisis similar in structure to the nuclei of higher organisms, but its behavior during division is quite different.
LOCATION OF ENZYMES IN
AZOTOBACTER AGILIS
Authors: Robrish Stanley A. , Marr Allen G.
Published: January 2020

Robrish, Stanley A.
(University of California, Davis)
and Allen G. Marr
. Location of enzymes in
Azotobacter agilis
. J. Bacteriol.
83:
158–168. 1962.—If the cells of
Azotobacter agilis
are disrupted by osmotic shock, respiratory enzymes and the compounds characteristic of cell wall and cytoplasmic membrane are recovered almost completely in large particles. The large particles obtained by osmotic shock were found by electron microscopy to consist of cell wall, cell membrane, and an internal membrane appearing as either vesicles or tubules in section. These envelopes are free of all the soluble cytoplasmic material and are essentially free of ribosomes.

Small particles obtained by osmotic shock are ribosomes; small particles obtained by sonic oscillation consist of both ribosomes and amorphous material, presumably fragments of the envelope.
STUDIES ON THE METABOLISM OF
SHIGELLA
IV. 3
Authors: Pan Sylvia F. , Yee Robert B. , Gezon Horace M.
Published: January 2020

Pan, Sylvia F.
(University of Pittsburgh, Pittsburgh, Pa.),
Robert B. Yee, and Horace M. Gezon
. Studies on the metabolism of
Shigella
. IV. Nutritional requirements of
Shigella flexneri
serotype 3. J. Bacteriol.
83:
61–65. 1962.—A study of the nutritional requirements of five strains of
Shigella flexneri
serotype 3 was carried out. Four of the strains could be cultured in a synthetic medium composed of a mineral salts glucose base, NH
4
H
2
PO
4
or an amino acid as the nitrogen source, and nicotinamide; the fifth one required the presence of both NH
4
H
2
PO
4
and an amino acid in the medium. Variation among the former strains in their nitrogen and vitamin requirements was observed. The least fastidious one produced maximal growth using the simple ammonium salt as its source of nitrogen and did not require the addition of nicotinamide. Two strains were moderately fastidious, producing better growth within 24 hr in the presence of
l
-aspartic acid instead of NH
4
H
2
PO
4
, and requiring nicotinamide as an accessory growth factor. The fourth strain was extremely fastidious, growing poorly or not at all in the synthetic medium. Incubation of large inocula of the fastidious strain in synthetic medium and over a prolonged period resulted in adaptation of the organism to the medium. Some of the adapted cultures grew readily in the presence of NH
4
H
2
PO
4
and did not require nicotinamide.
PROPERTIES OF TWO REGULATING GENES FOR ALKALINE PHOSPHATASE
Authors: Garen A. , Echols H.
Published: January 2020

Garen
, A. (University of Pennsylvania, Philadelphia)
and H. Echols
. Properties of two regulating genes for alkaline phosphatase. J. Bacteriol.
83:
297–300. 1962.—A constitutive mutation in one of the two regulating genes for alkaline phosphatase has two effects on the synthesis of the enzyme: repression of synthesis is blocked, and the cell's capacity to produce the enzyme is reduced. The behavior of this type of mutation has been studied in heterozygotes. The results suggest that the product of this regulating gene functions as an inducer as well as a repressor.
AEROBIC RESPIRATORY METABOLISM OF
STAPHYLOCOCCUS AUREUS
FROM AN INFECTED ANIMAL
Authors: Gellenbeck S. Mercy
Published: January 2020

Gellenbeck, S. Mercy
(Catholic University, Washington, D. C.). Aerobic respiratory metabolism of
Staphylococcus aureus
from an infected animal. J. Bacteriol.
83:
450–455. 1962.—The separation of
Staphylococcus aureus
from the tissue fluids of an infected guinea pig has allowed a comparison of cells (GPR) separated in this manner with the same strain (PR847) grown on an artificial medium.

In general, the respiratory response of organisms separated from tissue fluid was higher than that of staphylococci grown in vitro, though endogenous respiration of the in vitro strain consistently averaged 50% higher than the GPR cells. The guinea pig serum, defined medium, Trypticase soy broth, and the guinea pig filtrate were the complex substrates, listed in order of the least to the most stimulatory. Omission of nicotinamide and thiamine from the defined medium resulted in a decrease of oxygen consumption for the PR847 strain, but not for the GPR cells; however, when several amino acids were eliminated from the defined medium, the oxygen uptake of the GPR cells was depressed more than that of the staphylococci grown in vitro. In glucose alone, the organisms separated from the tissue fluid respired over 30% more effectively than the in vitro staphylococci. The filtrate, whether whole or boiled, provided a substrate in which organisms from both sources approximately doubled their oxygen uptake over that of either whole or boiled serum. Soluble components of the 50% ammonium sulfate fractionation of the filtrate stimulated GPR and PR847 cells more than did the 100% ammonium sulfate fraction under the conditions employed.
INACTIVATION OF THE T-EVEN COLIPHAGES BY PYROPHOSPHATE
Authors: Van Vunakis Helen , Herriott Roger M.
Published: January 2020

Van Vunakis, Helen
(Brandeis University, Waltham, Mass.)
and Roger M. Herriott
. Inactivation of the T-even coliphages by pyrophosphate. J. Bacteriol.
83:
590–596. 1962.—Pyrophosphate liberates the deoxyribonucleic acid from the T-even coliphages. The reaction is dependent on pH, temperature, time, and ionic environment. The reaction can be inhibited by magnesium, putrescine, spermidine, and neutral molecules above a certain molecular weight. Possible mechanisms of the reaction are discussed.
STUDIES IN METABOLIC SPECTRA IV
Authors: Cheng Lorraine , Snell J. F.
Published: January 2020

Cheng, Lorraine
(Radiobiochemistry Department, Chas. Pfizer & Co., Inc., Maywood, N. J.)
and J. F. Snell
. Studies in metabolic spectra. IV. Effects of tetracyclines, some of their derivatives, and chloramphenicol on accumulation of glutamic acid in
Escherichia coli
. J. Bacteriol.
83:
711–719. 1962.—
Escherichia coli
strain 21 was incubated in the Warburg apparatus at 37 C with sodium acetate-2-C
14
and 0.1 μmole/ml of various test compounds. Up to 1 hr, de novo C
14
-glutamic acid (synthesized from the C
14
-acetate precursor) accumulation in the fermentation broth was found to be a common phenomenon for the control cells and cells treated with oxytetracycline, chlortetracycline, tetracycline, and chloramphenicol. Subsequently, C
14
-glutamic acid continued to accumulate in the broth of the inhibited cells, but began to disappear from the broth of the control cells. During the first half hour, the rate of accumulation was most rapid in the presence of oxytetracycline. At 3 hr the total de nova C
14
-glutamic acid was found to be the same whether cells were treated with oxytetracycline or not. However, the distribution of this glutamic acid was different. In the oxytetracycline-treated cells, more than 87% of the total de nova C
14
-glutamic acid was in the broth, and only 13% was incorporated into the cell residue. In the control cells, no C
14
-glutamic acid was found in the broth, although 67% was in the cell residue. The possibility that the tetracyclines and chloramphenicol have different modes of action, and that oxytetracycline inhibits the incorporation of
d
-glutamic acid into the cell wall and membrane material in
E. coli
21, was discussed.
SELECTIVE AND REVERSIBLE INHIBITION OF THE SYNTHESIS OF BACTERIAL DEOXYRIBONUCLEIC ACID BY PHENETHYL ALCOHOL
Authors: Berrah Ghoulem , Konetzka Walter A.
Published: January 2020

Berrah, Ghoulem
(Indiana University, Bloomington)
and Walter A. Konetzka
. Selective and reversible inhibition of the synthesis of bacterial deoxyribonucleic acid by phenethyl alcohol. J. Bacteriol.
83:
738–744. 1962.—The selective inhibitory effects of phenethyl alcohol on gram-negative bacteria were confirmed with a variety of species. At a concentration of 0.25%, phenethyl alcohol was bacteriostatic for gram-negative bacteria; gram-positive cells were unaffected.
Pseudomonas fluorescens
required higher concentrations of the compound for inhibition than did the other gram-negative bacteria, and the gram-positive, acid-fast mycobacteria resembled the majority of gram-negative bacteria in sensitivity.

In the presence of phenethyl alcohol, gram-negative cells formed long filaments. There was no net synthesis of deoxyribonucleic acid (DNA) in such cells, whereas protein and ribonucleic acid (RNA) syntheses were unaffected. Upon removal of phenethyl alcohol, multiplication of the cells immediately ensued, with concomitant DNA synthesis. Yeast extract stimulated both RNA and protein synthesis in phenethyl alcohol-treated
Escherichia coli
, but no detectable stimulation of DNA synthesis occurred under these conditions.
RELATION OF THE IRON OXIDIZER,
THIOBACILLUS FERROOXIDANS
, TO THIOSULFATE
Authors: Colmer Arthur R.
Published: January 2020

Colmer, Arthur
R. (Louisiana State University, Baton Rouge). Relation of the iron oxidizer,
Thiobacillus ferrooxidans
, to thiosulfate. J. Bacteriol.
83:
761–765. 1962.—A restudy has been made of
Thiobacillus ferrooxidans
secured from the acid drainage of some northern West Virginia coal mines. Cultures isolated from ferrous iron agar and then subcultured for 85 consecutive transfers in thiosulfate broth during a period of 14 months were able to use ferrous iron as their energy source when returned to ferrous iron broth.

Thiosulfate utilization was quantitatively followed by iodine titration and pH change; ferrous iron oxidation was quantitatively determined by use of 1,10-phenanthroline.

Characteristic colonial forms were produced by
T. ferrooxidans
growing on thiosulfate agar irrespective of whether the inoculum was from iron broth or thiosulfate broth.
QUANTITY AND FATTY ACID COMPOSITION OF LIPID EXTRACTED FROM CELLS OF
STREPTOCOCCUS LACTIS
Authors: Macleod Patricia , Jensen R. G. , Gander G. W. , Sampugna J.
Published: January 2020

MacLeod, Patricia
(University of Connecticut, Storrs), R. G.
Jensen, G. W. Gander, and J. Sampugna
. Quantity and fatty acid composition of lipid extracted from cells of
Streptococcus lactis
. J. Bacteriol.
83:
806–810. 1962.—A method for the extraction of lipid from bacterial cells is described. Lysozyme-treated cells of
Streptococcus lactis
yielded 5% of their dry weight as lipid, whereas cells not treated with lysozyme yielded only 3% lipid.

More than two-thirds of the bacterial lipid extracted was tentatively classified as phospholipid, based on the elution behavior of this fraction on silicic acid columns when chloroform and methanol were the eluting solvents. The following five major fatty acids were present in all lipid fractions isolated: myristic, palmitic, palmitoleic, lactobacillic, and an 18-carbon acid possessing one double bond, which may actually be oleic acid or a mixture of oleic and one or more of its isomers. These acids comprised more than 85% of the acids found, as indicated by gas-liquid chromatography of their methyl esters. Since lactobacillic acid accounted for about 20% of the fatty acids extracted from cells of
S. lactis
, this organism may prove to be a ready source of this comparatively rare acid.