bluuebunny/crossref_metadata_2025 huggingface dataset:
A presence–absence (P–A) test providing sensitive and inexpensive detection of coliforms, fecal coliforms, and fecal streptococci in municipal drinking water supplies
Authors: Clark J. A.
Published: February 2010

A simple presence–absence (P–A) test was developed to provide a more economical and more sensitive method for conducting coliform analyses on municipal drinking water samples than the membrane filter (MF) technique. Over ninety percent of these samples routinely gave negative results by the MF method. A modified MacConkey broth, enriched to improve on acid and gas production by coliforms, was the isolation medium for the presumptive part of the P–A test.Parallel analyses of water samples were made by both the P–A and MF methods. Confirmatory tests established the reliability of the respective procedures to detect coliform bacteria. A statistical analysis of the results showed that the P–A test was more sensitive for detecting lower levels of pollution than the MF technique. Many of the confirmed positive P–A results came from P–A bottles that produced presumptive positive tests only after an extended incubation period of two to five days.The P–A test was about five times less expensive than the MF technique and by adding a few simple tests, the P–A procedure could give information on the presence of both fecal coliforms and fecal streptococci. For several samples, fecal streptococci were found by P–A tests in the absence of detectable coliform bacteria by either the MF or P–A methods of analysis.
Formation of the nitrogen-fixing enzyme system in Azotobacter vinelandii
Authors: Strandberg G. W. , Wilson P. W.
Published: February 2010

The formation and activity of nitrogenase2 in Azotobacter vinelandii OP was examined using a cell-free assay system. A lag period of about 30 min occurred between the exhaustion of the combined nitrogen source and growth on N2. Cells grown on ammonium acetate or potassium nitrate had no detectable nitrogenase activity. Nitrogenase activity appeared in cells, grown under a flowing gas phase of 20% O2 – 60% He, about 45 min after the exhaustion of ammonia. Nitrogenase formation was inhibited in a closed system with an atmosphere containing 40% O2 but not by one containing 20% O2. Hydrogen did not inhibit enzyme formation. The question of whether N2 is required for the formation of the enzyme could not be answered as this gas could not be completely eliminated from the growth system. Chloramphenicol prevented the formation of the enzyme and inhibited nitrogen fixation in whole cells, but had no effect on cell-free enzyme activity. A brief rise in turbidity which occurred during nitrogenase formation appeared to be due to a color change in the cells from reddish brown to dark brown. Spectrophotometric examination of extracts from ammonia- and N2-grown cells did not reveal any components responsible for this color difference, but this result may reflect only the presence of interfering substances in the crude extract.
The utilization of purines and pyrimidines by yeasts
Authors: LaRue T. A. , Spencer J. F. T.
Published: February 2010

Purines and pyrimidines were tested singly as sole nitrogen sources for 123 species of yeast. The utilization of thymine was confined almost exclusively to the Lipomyces and Sporobolomyces. The utilization of purines and pyrimidines by Saccharomyces with reniform spores did not differ from that of other Saccharomyces species.
Extension of bundles of cellulose microfibrils on agar surfaces by Acetobacter xylinum
Authors: Gibson E. J. , Colvin J. Ross
Published: February 2010

The extension of bundles of bacterial cellulose microfibrils on agar surfaces was investigated using pseudoreplicas in the electron microscope. Two classes of bundles were distinguishable; those which were composed of many short individual microfibrils of nearly uniform length (1–3 μ) and those in which there were only a few long microfibrils (> 50 μ). The growth pattern of single straight cellulose microfibrils, the proportion of bundles containing many short microfibrils and the extent of coiling of microfibrils were influenced strongly by the sample of agar used to form the surface. These observations are consistent with the suggestion that the mode of extension of bacterial cellulose microfibrils is sensitive to the concentration of an extracellular precursor in small pools on the agar surface.
Growth of psychrophilic microorganisms at subzero temperatures
Authors: Larkin J. M. , Stokes J. L.
Published: February 2010

In an attempt to find a suitable medium for determining the ability of psychrophilic bacteria and yeasts to grow at subzero temperatures, six antifreeze compounds were added individually and in combination to Trypticase soy broth and agar. The media were tested for their ability to support good growth of psychrophilic bacteria at 20 °C and to resist freezing at subzero temperatures. In general, media which supported good growth at 20 °C froze at −7 °C, whereas media which did not freeze at −7 °C did not support good growth at 20 °C. In supercooled liquid media, however, three species of Bacillus grew at −2 °C, one at −4.5 °C, and five at −5 to −7 °C. Generation times were approximately 4 days at −2 °C, 7 days at −4.5 °C, and 9 to 11 days at −5 to −7 °C. On supercooled growth-supporting agar media, two Gram-positive cocci, one Gram-negative rod, and four species of yeast grew at −2 °C. The latter also grew at −4.5 °C. Three species of Bacillus grew at −7 °C, and two at −10 °C.
Studies of active and passive immunity in animals inoculated with Toxoplasma gondii
Authors: Foster B. G. , McCulloch William F.
Published: February 2010

It has been shown that cytoplasm-modifying antibodies as demonstrated by the Sabin–Feldman dye test were elicited in the guinea pig after inoculation of phenol-killed toxoplasma organisms and that the addition of an adjuvant to the suspension induced immunity to reinfection in the animals. Protection from reinfection was also provided by recovery from laboratory-induced infection.Passive immunity studies were conducted using pooled antiserum from actively immunized guinea pigs. A slight increase in average survival time was shown in mice when the sera were used. The exception was in the case of serum from guinea pigs injected with an aqueous suspension of phenol-killed organisms. When "accessory factor" was incorporated with these antisera there was an additional increase in survival time in mice, but this increase was not statistically significant in every case.It was shown that neither vaccination nor recovery from experimental infection, even in the presence of very high titers of dye test antibodies, completely prevented the persistence of toxoplasma in various organs of the guinea pigs which had been challenged.
The mechanism of action of griseofulvin
Authors: Huber Floyd M. , Gottlieb David
Published: February 2010

Griseofulvin had no effect on the respiration of Botrytis cinerea but, nevertheless, inhibited growth and caused abnormal hyphal formations, including stunting, spiraling, thickening of the cell wall, and disorientation of growth. Treated cells had an increase in total deoxyribonucleic acid and phosphorus but not in protein, carbohydrate, lipid, and ribonucleic acid. Griseofulvin-treated cells synthesized DNA from labelled glucose and glycine continuously and for much longer periods than control cells so that their total DNA content was greater than that in untreated cells. However, the antibiotic allowed slightly less incorporation with aspartic acid -U-14C as the precursor than the controls. Griseofulvin caused 25 to 50% increased incorporation of carbon into RNA from glucose and glycine but the increases were not due to a prolongation of the synthetic period, and again aspartic acid incorporation was slightly decreased. Griseofulvin was bound to the particulate parts of the cell and was especially high in the lipid fraction of the cell. The antibiotic was not bound to DNA or to RNA.
Ukauwa virus proliferation in mosquitoes
Authors: Ogunbi Oladeinde
Published: February 2010

Ukauwa virus, a Bunyamwera group arbovirus endemic in the Ethiopian zoogeographic region, multiplied in the tissues of North American mosquito species Aedes canadensis (Theobald) and Aedes triseriatus (Say) after intrathoracic inoculation. This virus also multiplied in laboratory-bred Aedes aegypti (L.) after both feeding and injection. Ukauwa virus now fulfills the biological criteria of an arbovirus. In these three mosquito species, after initial detection of infective virus immediately after inoculation, an eclipse phase with lack of detection of infectivity was observed 6 hours later, and was followed by initial recovery of virus (1.0 log mouse LD50) at 12 hours and thereafter steady virus increments in thorax, salivary glands, gut, and legs which reached maximum titers of 5.4 to 6.3 log mouse LD50 in 4 days. In A. aegypti fed Ukauwa virus no infectivity was detected during the first 8 days after the meal. After initial detection of infective virus (3.0 log mouse LD50) on day 10, maximum titers of 4.3 to 5.3 log mouse LD50 were reached 4 days later.A. aegypti transmitted Ukauwa virus to weaned mice on the 12th and 14th days after an infective blood meal, when virus titers in the salivary glands exceeded 4.3 log mouse LD50. The infection threshold of Ukauwa virus for A. aegypti by feeding was 4.7 log mouse LD50 per 0.002 ml.
Mycotoxins from food-borne fungi
Authors: Walbeek W. van , Scott P. M. , Thatcher F. S.
Published: February 2010

1.A wide range of fungi have been isolated from foodstuffs, and their ability to produce aflatoxins and, in some instances, ochratoxin A, was determined. Specimens were obtained from households (including samples associated with illness), from retail stores, and from processing plants. Of 128 fungi, isolated from 74 food samples, and cultured on complex media and on shredded wheat, 16 were found to produce toxins. Alfatoxins were produced not only by Aspergillus flavus isolates but also by a Rhizopus sp. and an Aspergillus ochraceus. Six strains identified as Aspergillus flavus var. columnaris formed aflatoxin B2 only. Ochratoxin A was produced by a Penicillium sp. as well as by A. ochraceus isolates.
Characteristics of Aerobacter beta-lactamase
Authors: Goldner M. , Glass D. G. , Fleming P. C.
Published: February 2010

In this investigation, Aerobacter cloacae is shown to inactivate cephalosporin by hydrolysis of its beta-lactam ring. This was demonstrated by iodine absorption and infrared absorption spectra.The values of the Michaelis constant obtained with cephalosporin C and deacetyl cephalosporin C indicate a great affinity of the Aerobacter's beta-lactamase for its substrate. The enzyme was most active at pH 7.0 and 37 C. Aqueous washings of the Aerobacter cells were a potent source of enzyme.The beta-lactamase of A. cloacae was active on both cephalosporin and penicillin. A higher rate of hydrolysis was observed with cephalosporin C and deacetyl cephalosporin C than with cephalothin and cephaloridine. The ratio of reaction rates on cephalosporin C to that on penicillin G was consistently of the order of 100 to 1. The activity on V, N, and especially the semisynthetic penicillins was also low.The A. cloacae enzyme was easily demonstrable in large amount without added inducer. By contrast, the activity of the beta-lactamase from Pseudomonas pyocyanea cannot be detected unless high concentrations of inducer are used.
The stability of the protective antigen and histamine-sensitizing factor of Bordetella pertussis to acid and alkali
Authors: Jakus Cvetka M. , McClure Lyn , Wardlaw A. C.
Published: February 2010

Pertussis sonic lysates were adjusted to a series of pH values between 3.0 and 11.0, held for 1 hour at room temperature, and then returned to neutrality and assayed for residual mouse protective antigen (MPA) and histamine-sensitizing factor (HSF) activities. The percentage in-activation of MPA at pH 3.0, 10.0, and 11.0 was respectively 30, 18, and 40 but only the last value is significantly different from the pH 7.2 control. The percentage inactivation of HSF in the same samples was 40, 29, and 75 respectively. Exposure to pH 11.0 had a significantly greater destructive effect on HSF than on MPA.These data may be of future value in helping to develop methods for purifying MPA, for they indicate that this factor is reasonably stable to pH within a usefully wide range.
Purification and structure of Semliki Forest virus isolated from mouse brain
Authors: Faulkner P. , McGee-Russell S. M.
Published: February 2010

Semliki Forest virus from brains of infected suckling mouse was separated by cesium chloride equilibrium density gradient centrifugation into two fractions, both able to agglutinate red blood cells of goose. The heavy fraction (HF density 1.24) had more infectivity, had a sedimentation coefficient of 285 S, and contained intact virus particles, diameter about 75 mμ. The light fraction (LF density 1.205) of equivalent HA (hemagglutinating activity), had less than 1% of the infectivity of the HF and did not contain intact virus particles. It consisted of "empty" virus particles and fragments of the fragile envelope material. The complete virus particle consists of an envelope of complex character surrounding a well-defined core. Shadow-cast preparations of HF show pointed and truncated shadows which suggest cubical symmetry, and the core of full particles, in thin sections, shows an angular, often pentagonal or hexagonal configuration. This suggests that the cubical symmetry of the full particle depends upon the fundamental symmetry of the core, which appears to be icosahedral.
Immunodiffusion and immunoelectrophoretic studies of reovirus antigens
Authors: Leers W.-D. , Rozee K. R. , Wardlaw A. C.
Published: February 2010

Immunodiffusion of reovirus antigens on cellulose acetate membranes revealed that these viruses possess at least one, and perhaps two, group-specific antigens and at least one type-specific antigen. The higher resolution attainable using immunoelectrophoresis permitted, with reovirus type 2 antigens, the demonstration of four group-specific and two type-specific precipitin lines. The simplicity of these techniques recommends them as suitable methods for a variety of problems dealing with antigenic differentiation of virus strains and subgroups.
A synthetic medium for germination, postgerminative development, and growth of spores of Clostridium roseum
Authors: Wooley Bennie C. , Collier Robert E.
Published: February 2010

A synthetic medium for Clostridium roseum was devised. This medium consisting of 18 amino acids, three vitamins, glucose, salts, and a buffer system supports the germination, postgerminative development, and growth of spores of this organism. Although the morphological and cultural characteristics of the cells are similar to those in Tris test medium, the medium fails to support the formation of normal resistant spores. As in the case of some other Clostridia, proteinaceous material in the form of Trypticase and thiamine are required for the complete phenotypic expression of the spore genome.
The nature of staphylococcal beta hemolysin. II Effect on mammalian cells
Authors: Wiseman G. M.
Published: February 2010

Purified beta hemolysin A was toxic to human amnion and monkey kidney and KB cells on the basis of trypan blue uptake, absence of pH changes in the medium, and inability of the cells to adhere to glass surfaces. Cells treated with the hemolysin were smaller than controls with granular cytoplasm and prominent nuclei. Rabbit and sheep leucocytes were unable to reduce the dye dichlorophenol–indophenol in the presence of the hemolysin but their ability to take up bacteria seemed unimpaired. Morphological changes in other mammalian cells were not found in leucocytes.
The axenic cultivation of Hexamita inflata from Crassostrea virginica
Authors: Khouw B. T. , McCurdy H. D. , Drinnan R. E.
Published: February 2010

Hexamita inflata in axenic culture by serial transfer in a beef serum or egg yolk enriched medium containing antibiotics.
Observed increase in methylated purines excreted by hamsters bearing adenovirus-12 induced tumors
Authors: McFarlane E. Sandra , Shaw Gloria J.
Published: February 2010

An examination of the urine of hamsters bearing adenovirus-12 induced tumors showed an elevated excretion of methylated purines. The weight of the animals increased 1 to 5% while the purines excreted increased 200%.
New methods of production and partial purification of an antiviral substance from Penicillium cyaneo-fulvum
Authors: David-West Tam S. , Cooke Patricia M. , Stevenson J. W.
Published: February 2010

A strain of Penicillium cyaneo-fulvum isolated in this laboratory elaborates an antiviral substance in Czapek-Dox broth which inhibits the multiplication of influenza A and B and Newcastle disease viruses in modified Maitland tissue cultures. However, the multiplication of these viruses as well as mumps virus was not inhibited when tested in embryonated hens' eggs. No antiphage activity was demonstrated against a ribonucleic acid containing phage (f2) and a single-stranded deoxyribonucleic acid containing phage [Formula: see text]. The antiviral substance in a semipurified form, derived by precipitation of impurities from the culture filtrates with acetone, contains sugars, amino acids, and nucleic acid components, and shows a peak at about 270 mμ in its ultraviolet absorption spectrum, with a 280 mμ/260 mμ ratio of 0.97. It is stable to heat, lyophilization, repeated freezing and thawing and it is not dialyzable. Results of enzyme inactivation of the active principle were not conclusive.
The mode of action of an antiviral substance from Penicillium cyaneo-fulvum
Authors: David-West Tam S. , Cooke Patricia M. , Stevenson J. W.
Published: February 2010

An antiviral substance elaborated in Czapek-Dox broth by a strain of Penicillium cyaneo-fulvum isolated in this laboratory, and active against influenza A virus (PR8), influenza B virus (Lee), and Newcastle disease virus (B1) in modified Maitland tissue cultures has been shown to act at an intracellular site in the viral replicative cycle. The substance neither blocks virus adsorption nor impedes the release of newly formed virus particles. It is not viricidal, does not interfere with the action of ths viral neuraminidase on red blood cells, and does not possess any haemagglutination or haemagglutination–inhibition activity. A comparison with other reported antiviral agents shows that the antiviral substance is different from those previously studied.
Purification and structure of rhapidosomes
Authors: Reichle R. E. , Lewin R. A.
Published: February 2010

A method for the purification of rhapidosomes from flexibacteria is described. The substructure of the purified rhapidosomes (as seen by electron microscopy) is shown and their resemblance to similar particles which are found in other bacteria is discussed.
Extracellular proteolytic enzymes of psychrophilic bacteria. I. Purification and some properties of enzymes of an obligately psychrophilic red-pigmented bacterium
Authors: Nunokawa Y. , McDonald I. J.
Published: February 2010

Proteinase in culture fluids of an obligately psychrophilic bacterium was precipitated by ammonium sulfate and fractionated by gel filtration and DEAE-cellulose chromatography. Three purified fractions (I-1, I-2, and III-1) with proteinase activity were obtained. On the basis of reactions and characteristics (i.e. effect of pH, heat, and metal ions on activity and stability, hydrolysis of synthetic peptides and of natural proteins) fractions I-1 and III-1 appeared to be very similar whereas fraction I-2 was different. When proteinase preparations were examined by electrophoresis, fractions I-1 and III-1 gave similar patterns; fraction I-2 gave a different one. From the results it is suggested that the organism produces two proteinases and that possibly fraction I-1 represents an aggregation of molecules of III-1 and that fraction I-2 is a different proteinase.
Responses of a psychrophilic marine bacterium to changes in its ionic environment
Authors: Korngold R. R. , Kushner D. J.
Published: February 2010

A psychrophilic marine bacterium was stable in cold seawater or in a solution containing 0.1 M Mg++ and 0.5 M NaCl. In water and in a number of monovalent salts, including up to 3.0 M NaCl, turbidity of suspensions fell and some intracellular material was released into the external medium. The cells first became swollen and pale under phase contrast optics and then disintegrated into amorphous aggregates. Divalent salts alone, some in very low concentrations, could maintain cell structure. Effectiveness was in the order Cu++ > Zn++ > Ni++ > Ca++ > Mn++ > Mg++. The polyamine, spermine, was ineffective. In the presence of 0.1 M Mg++, NaCl and, less effectively, LiCl and RbCl could maintain structure, but KCl, NH4Cl, CsCl, glucose, and sucrose could not. Sodium phosphate, pH 7.0, caused lysis but other sodium salts maintained structure in the presence of Mg++. For growth, Mg++, NaCl, and traces of other ions were required.Phosphatidases attacking cells at 25 °C and higher required salts for maximum activity. The turbidity of water-lysed cells or of envelopes prepared from mechanically broken cells fell at 25 °C and higher; this fall was also dependent on the presence of salts. If cells were lysed in distilled water, or broken mechanically in the presence of salts, more than half their lipid phosphorus and hexosamine was released from material sedimenting after 30 min at 15 000 × g but these materials were not degraded into other substances. The released material seemed bound to smaller particles, since most of it sedimented after 1 hour at 100 000 × g. The lipid composition of smaller and larger particles, and of whole cells, was the same.
Pythium and Mortierella in soils of Ontario forest nurseries
Authors: Vaartaja O.
Published: February 2010

Populations of Pythium and Mortierella species were estimated by plating surface soils in agar media containing pentachloronitrobenzene, pimaricin, and bacterial antibiotics. Pythium spp. were found in 16 of 17 Ontario soils, mainly seedbed soils in forest nurseries. There was significant variation in the mean population density of Pythium propagules between two seedbeds sampled in each nursery and between the nurseries. The population was high in 10 soils (7 to 57 propagules per cm3) with P. irregulare as the dominant species. The following species were fairly abundant (in decreasing order): P. rostratum, P. ultimum, and P. oligandrum. Pythium was not significantly correlated with properties of the nurseries or with populations of Mortierella, bacteria, Streptomyces, and heat-tolerant fungi. The Pythium population was high only in old nurseries. Mortierella spp. occurred in all soils varying from 1 to 500 propagules per cm3.
Development of selenite egg yolk agar
Authors: Elliott L. P.
Published: February 2010

A selenite egg yolk medium was developed for plating particularly heavily contaminated materials. This medium is selective for staphylococci and gives added information concerning their egg yolk reaction.
"Steady-state" competence for bacterial transformation
Authors: Eichhorn Herbert H. , Arikawa Shigeyo , Zamenhof Stephen
Published: February 2010

The cells of Bacillus subtilis, grown in minimal media, are known to become competent for transformation for a short period at a specific phase of ceil growth. In the present work the cells (strain 168 ind−) were grown in continuous culture (chemostat; glucose limiting, generation time 4 h, 37 °C). Aliquots were removed at 20- to 24-h intervals and immediately tested for competence. The viability (41 h) was 97%. The initial very low competence increased up to 200-fold within the 24 h and remained at this high, slowly decreasing level for at least 168 h. It is concluded that a long-lasting competence may develop and persist in the cells in continuous culture ("steady-state"), without demonstrable harmful effects to the population.
Cell division in a species of Erwinia. X. Morphology of the nuclear body in filaments produced by growth in the presence of D-serine
Authors: Grula E. A. , Smith Gerald L. , Grula Mary M.
Published: February 2010

Filamentous cells of Erwinia sp. produced by growth in the presence of D-serine possess nuclear bodies that are not dividing normally. The nuclear bodies can be highly convoluted and continuous throughout large portions of the filaments. Possible reasons for failure of the nuclear body to periodically divide and suggested relationships to division of the cell are discussed.
Sorption between microorganisms and clay minerals as determined by the electrical sensing zone particle analyzer
Authors: Santoro T. , Stotzky G.
Published: February 2010

Sorption between microbial cells and clay minerals was determined by measuring changes in particle size distribution with an electronic particle counter. Sorption increased as the valency of the cations present on the clay and in the suspending electrolyte increased. Neither the size, motility, or Gram reaction of bacteria nor the size of the clay appeared to influence sorption. Sorption occurred between bacteria and montmorillonite homoionic to monovalent cations only at pH 2 to 4, but did not occur at any pH with yeast cells, which sorbed only in the presence of trivalent cations. Heat-killed cells of yeast lost their ability to sorb, whereas cells killed with benzalkonium chloride did not. The possible implications of these results in sorption of microorganisms in natural habitats are discussed.
Ascospore germination in Byssochlamys nivea
Authors: Yates A. R. , Seaman A. , Woodbine M.
Published: February 2010

Germination of the ascospores of Byssochlamys nivea required a heat shock at 75° for 5 min, and acetate ion. Aeration and pH 4.0–4.5 further enhanced germination. No other trichloroacetic acid cycle compounds were stimulatory, and a survey of 18 amino acids and a number of miscellaneous compounds did not reveal any other germination factors. Extreme variation throughout the investigation suggested that other undisclosed factors were involved.
Preparation and properties of diphtheria toxoids in submerged culture. II. Purification, detoxification, antigenicity, and stability
Authors: Stainer D. W.
Published: February 2010

Cornyebacterium diphtheriae was grown in submerged culture using a new semisynthetic medium, and high-potency diphtheria toxins were produced. These toxins were purified before detoxification by formalin–lysine mixtures. The resultant toxoids possessed a high degree of purity (Lf/mg non-dialyzable nitrogen), gave good antigenic responses in animals, and showed no tendency to revert to toxin. Toxins which had been detoxified with formalin alone before purification, however, showed marked reversion when diluted and stored at 25 or 34 °C. When tested in guinea pigs the lysine-treated toxoids were shown to possess good immunizing capacity, and no significant decreases in the antigenic potencies were observed in samples stored for prolonged periods of time at elevated temperatures.
Growth and nucleic acid synthesis of Salmonella typhimurium inhibited by α-methylmethionine
Authors: Smith Robert C.
Published: February 2010

The addition of α-methylmethionine to exponentially growing cultures of Salmonella typhimurium or Escherichia coli resulted in an immediate cessation of growth with low concentrations of the analogue. After a lag period, the length of which was dependent on the optical density of the culture, growth resumed at a rate characteristically slower than that of an untreated culture. Chemical analyses showed that the rate of synthesis of ribonucleic acid and protein by S. typhimurium had a pattern similar to the curve for optical density. However, deoxyribonucleic acid and cell numbers continued to increase at the normal rate for about 30 minutes, then slowed, and changed to the rate characteristic of cells treated with the analogue. Incorporation of thymine-14C, uracil-14C, and leucine-14C by the thymine auxotroph E. coli 15T− confirmed the chemical analyses. After 25 minutes the cells of the culture treated with α-methylmethionine had incorporated only 15% of the uracil and 26% of the leucine as that of a control culture. The optical density was 30% that of a control culture. Thymine incorporation was 92% that of a control culture.
Studies on the carbon, nitrogen, and vitamin nutrition of Stemphylium radicinum
Authors: Curren T.
Published: February 2010

Two isolates of Stemphylium radicinum were grown in a chemically defined liquid medium. Both isolates grew best on organic nitrogen compounds and in the absence of a buffer grew poorly on ammonium nitrogen. KNO3 was a good source of nitrogen for isolate No. 2, but not for No. 1.Xylose, sucrose, and glucose were the best carbon sources for S. radicinum, although isolate No. 1 produced more mycelium on pectin. Arabinose and cellulose were poor sources of carbon.Isolate No. 2 grew better than did isolate No. 1 on most media.The two isolates differed in their vitamin requirements. Isolate No. 1 was deficient for thiamine while isolate No. 2 did not need added vitamin for normal growth.
Phosphorus deficiency and phosphate uptake in the blue-green alga Anacystis nidulans
Authors: Batterton J. C. , Baalen C. Van
Published: February 2010

The normal level of phosphorus in Anacystis nidulans is approximately 3.7 μg Pi/mm3 cells. This value fell to 0.5 μg Pi/mm3 cells under prolonged starvation. Even at low cellular phosphate levels, cells were viable and continued to divide slowly. With cells containing approximately 1.5 μg Pi/mm3 cells a rapid dark uptake (15 minutes) of 0.8 μg Pi/mm3 cells was found. Data obtained in the rapid dark fixation suggest that approximately 25% of the total cellular phosphorus is possibly bound on specific sites. Light had little effect on this first phase of phosphate uptake. The subsequent uptake to the normal phosphorus content per cell and return to normal growth rate required light and nitrogen.Coincident with the rapid dark phosphate incorporation, synthesis of ATP began and continued, rising far above the level of normal cells. The rate of ATP formation was not influenced by light, but was blocked by anaerobic conditions or several classical inhibitors of the electron transport chain.
β-Lactamase activity of Escherichia intermedia
Authors: Huber F. M. , Caltrider P. G. , Noble Susanne
Published: February 2010

Escherichia intermedia was found to produce a β-lactamase that hydrolyzed several penicillin and cephalosporin C derivatives. Culture conditions affecting production of the enzyme were studied. The enzyme was non-inducible and cell-bound. Growth temperature, medium, and physiological age had a marked effect on production of the enzyme. Properties of the enzyme were studied with intact cells and with a cell-free preparation. Although the β-lactamase of E. intermedia was different in some respects to that produced by gram-positive organisms, it was found to have properties similar to the β-lactamases of gram-negative organisms. 6-Aminopenicillanic acid was cleaved by the enzyme, but 7-aminocephalosporanic acid was resistant to cleavage. The rate of hydrolysis by intact cells and the purified preparation was influenced by the type of N-acyl sidechain of 7-aminocephalosporanic acid and 6-aminopenicillanic acid. The desacetoxy derivatives of cephalosporin C and cephalothin were hydrolyzed less rapidly than the parent compounds. The specific activity of the intact cells on cephalonium and methicillin was substantially less than that of the purified preparation.
Microbiology of domestic wastes. I. Physiological activity of bacteria indigenous to lagoon operation as a function of seasonal change
Authors: Halvorson Harvest , Ishaque M. , Lees H.
Published: February 2010

The physiological activity of bacteria indigenous to a mid-continental domestic wastes disposal unit (lagoon) was studied over a period extending from mid-May to the beginning of December, 1965. A rigorous climate induces a layer of ice over the lagoon for approximately 5 months of the year; this study entailed the interval under ice-free conditions during the first year of operation. Samples were collected roughly at weekly intervals and the activity of the bacteria free of algae was studied against several arbitrarily selected organic substrates. The activity was found to be a function of (a) the number of bacteria, (b) the temperature of the lagoon, and (c) the nature of the test substrate. The most rapid rates of oxidation occurred with casamino acids, acetate, and palmitate. Glucose, egg albumin, and Liqui-nox, a biodegradable detergent, were oxidized in a variable manner. Maximum activity occurred at 23 °C, the highest temperature reached by the lagoon during the summer. The rates of oxidation decreased markedly when the temperature decreased as a result of the onset of fall but all activities were not affected equally by the same temperature change.
Isolation of Gallionella ferruginea by use of formalin
Authors: Nunley Jay W. , Krieg Noel R.
Published: February 2010

In seven out of ten separate trials, contaminants in cultures of Gallionella ferruginea were eliminated by incubation of the crude culture for 1–2 days in Wolfe's medium containing 0.5% formalin. Purity was judged microscopically and also by the absence of contaminant growth in a variety of heterotrophic and autotrophic test media. Parallel cultures not treated with formalin exhibited growth of contaminants in most test media. Pure cultures of G. ferruginea have been maintained by serial transfer for at least 14 months and in continuous flow culture for at least 3 months. Preservation has been possible by storage at −80 °C in 15% glycerol. G. ferruginea in impure culture grew as a microaerophilic band closer to the surface of the fluid in the culture bottles than it did in pure culture; in the pure culture state it grew in a dense mat on the surface of the submerged ferrous sulfide agar. This difference probably resulted from the absence of oxygen-utilizing contaminants in the pure state.
Oxidation of hydrocarbons by microorganisms isolated from soil
Authors: Perry Jerome J. , Scheld H. William
Published: February 2010

Fertile soil contains significant numbers of microorganisms that can utilize hydrocarbons as a sole source of carbon and energy. Soils taken from oil fields contain an increased percentage of the total microbial population that can grow on petroleum hydrocarbons. Microorganisms isolated on a variety of non-hydrocarbon substrates were tested for the ability to grow at the expense of n-tridecane. Those isolated on substrates that require an oxygenase for assimilation grew on the n-alkane in much greater numbers than organisms isolated on substrates that do not. One organism isolated on o-phthalic acid simultaneously induced to propane and o-phthalate after growth on glucose. The possible mechanism(s) involved are discussed.
Influence of acetohydroxamic acid on some activities in vitro of the rumen microbiota
Authors: Jones G. A.
Published: February 2010

When acetohydroxamic acid was incubated with washed suspensions of bovine rumen microorganisms the urease activity of the suspensions was depressed; activity could not be restored by the addition of divalent cations which, in the absence of acetohydroxamic acid, stimulated the urease activity of the cells. Acetohydroxamic acid was slowly degraded by the rumen microbiota. When the compound was incorporated into a non-selective medium for the enumeration of rumen bacteria it completely prevented visible colony development by some components of the inoculum and retarded the rate of multiplication of others. Acetohydroxamic acid inhibited the production of volatile fatty acids from added cellulose in strained rumen fluid and modified the molar proportions of acetate, propionate, and butyrate produced from the substrate; whereas in the absence of acetohydroxamic acid propionate production was favored at the expense of acetate; in its presence the acetate:propionate ratio remained constant. The effect of acetohydroxamic acid upon rumen microbial activities in vitro was therefore not limited to inhibition of rumen urease. It was impossible, however, to infer from the results obtained whether the potential value of the compound as a urease inhibitor in vivo would be diminished for this reason; this is because the influence of acetohydroxamic acid on the rumen microbiota in vivo is probably subject to modification by factors, such as the composition of the animal's diet, which were not investigated.
Survival, transmission, and taxonomy of Pseudomonas syringae van Hall, the causal organism of bacterial brown spot of bean (Phaseolus vulgaris L.)
Authors: Hoitink Harry A. J. , Hagedorn D. J. , McCoy Elizabeth
Published: February 2010

Pseudomonas syringae van Hall was shown to be transmitted on seed of bean (Phaseolus vulgaris L.). The pathogen survived in bean field soil until April but not until May. Isolates studied were pathogenic to pea, but not to red clover, white dutch clover, ladino clover, alfalfa, or white lupine. Attempts to isolate P. syringae as a pathogen or as an epiphyte from plants in fence lines and wind breaks surrounding diseased bean fields failed. It was concluded that infected seed is a principal source of the bacterial brown spot pathogen in Wisconsin. Routine bacteriological tests including the utilization of 12 carbohydrates, six organic acids, and 30 other diagnostic tests did not differentiate P. syringae and P. pisi Sackett. These two species differed with respect to acrylamide disc-gel electrophoretic protein patterns, electrophoretic peroxidase isozymes, toxin production, and host range. Isolates of P. syringae produced a toxin with characteristics of syringomycin, whereas isolates of P. pisi did not produce such a toxin.
Lysogenic conversion of O antigens in Salmonella group C1
Authors: Escobar Mario R. , Edwards Phillip R.
Published: February 2010

Lysogenic conversion among certain serotypes in Salmonella O group C1 reveals that all 62,7 strains of S. choleraesuis var. kunzendorf, except for a unique strain of the same biotype, can be converted to 61,7 by phages released spontaneously from 61,7 strains of S. choleraesuis and S. choleraesuis var. kunzendorf but absent in 62,7 variants of the same species. An exceptional strain of S. montevideo (61,7) is lysogenic for a phage which converts all 62,7 strains of S. choleraesuis var. kunzendorf to 61,7. The 62,7 strain of S. choleraesuis var. kunzendorf, which is resistant to conversion only by phages released from 61,7 strains of the same biotype, is in turn lysogenic for a "blocking phage" which lysogenizes all other 62,7 strains, converting them so that they are no longer susceptible to the phages from 617 strain of S. choleraesuis and S. choleraesuis var. kunzendorf; however, they are still susceptible to conversion by the 61,7-Montevideo phage. Many strains from other Salmonella C1-group serotypes are also lysogenic, and their temperate phages lysogenize susceptible strains which are within the same group, but no converting properties could be determined. An attempt was made to differentiate these phages according to various criteria.
Mechanism of decomposition of jute and cellulose by a Corticium species
Authors: Ghosh B. L. , Bose R. G. , Basu S. N.
Published: February 2010

Growth of a Corticium species on jute fabric exposed to 100% relative humidity led to staining and deterioration of the fiber, showing evidence of considerable oxalic acid production and cellulase activity. Pure oxalic acid in excess of quantities produced by the organism did not degrade jute fabric to any comparable extent, and decomposition of cotton cloth was even less pronounced. Strength losses of jute and cotton yarn as a result of treatment with the cell-free culture filtrate were greater by far than those caused by the autoclaved filtrate, again suggesting cellulase action rather than oxalic acid as the main cause for deterioration.When the fungus was grown on jute and cotton fabrics suspended in a nutrient solution, losses in fabric strength were lower.Filter paper suffered a very small loss in weight when used as substrate for growth. The cellulase appeared to be random-splitting, adaptive, and extracellular in character, showing optimum activity at pH 4.0 and temperature 58 °C.
New observations on the determination of bacterial lipid phosphorus
Authors: Toennies G. , Das D. N. , Feng F.
Published: February 2010

A microprocedure potentially useful in serial determinations of phosphatides or lipid phosphorus is described, in which lipid liberation is accomplished by heating bacterial specimens with aqueous methanol under pressure in Teflon-capped tubes. Data are also presented which suggest that the ease of lipid removal from bacterial cells is a negative function of their wall and membrane content.
Enzymatic reversibility of flagellar immobilization
Authors: Dipierro J. M. , Doetsch R. N.
Published: February 2010

The agglutination and consequent immobilization of actively motile cultures of Escherichia coli and Pseudomonas fluorescens by specific flagellar antisera may be reversed by treating them with proteolytic enzymes such as trypsin, pepsin, or bromelin. Reversion is not possible if more than 4 h elapse before it is attempted. Immune globulin fragments prevent immobilization when cultures are subsequently exposed to divalent sera; hence, the bacteria continue to be actively motile although their flagella are now "loaded" with globulin fragments. Distinct behavior differences are noted both when monotrichously flagellated (Pseudomonas) and peritrichously flagellated (Escherichia) bacteria are immobilized, as well as when such immobilization is reversed.
The cell wall of Penicillium roquefortii
Authors: Applegarth D. A. , Bozoian G.
Published: February 2010

The cell wall of Penicillium roquefortii has been shown to contain predominantly glucan, chitin, and protein. There is no evidence for any mucopeptide-like structure.
A microbial interaction involving combined mutualism and inhibition
Authors: Yeoh H. T. , Bungay H. R. , Krieg N. R.
Published: February 2010

A defined medium deficient in both niacin and biotin supported neither Proteus vulgaris nor Bacillus polymyxa in pure culture, but a mixed culture grew well. Presumably each can supply a vitamin requirement for the other. Continuous flow cultivation of mixed cultures exhibited oscillatory population levels of each species. P. vulgaris produced an inhibitor which accumulated to inhibit growth of B. polymyxa, and the vitamin interdependency caused the former to also cease growing. After continued pumping diluted the inhibitor, growth resumed. The inhibitor seems to be a protein, because proteolytic enzymes added to the culture gave higher, non-oscillatory population levels.
Nucleic acid methylase activity in hamsters bearing tumors induced by adenovirus-12
Authors: McFarlane E. Sandra , Shaw Gloria J.
Published: February 2010

Cell-free extracts of tumor cells induced by adenovirus-12 derived from Syrian hamsters possessed higher transfer RNA (tRNA) methylase activity than cell-free extracts from liver, lung, kidney, spleen, or skin and muscle. No difference was found between normal and tumor cell free extracts in the methylation of DNA or ribosomal RNA.The tRNA methylase activities in cell-free extracts from hamster embryos were in the range found for normal adult tissue extracts. It appears therefore that the increase in tRNA methylase is characteristic of the tumor cells, and is not a result of their rapid growth.
Studies on the histamine-sensitizing factor of Bordetella pertussis by density gradient centrifugation
Authors: Griffiths B. W. , Mason M. A.
Published: February 2010

The density gradient centrifugation of the histamine-sensitizing factor (HSF) of B. pertussis extracts in admixture with purified foreign proteins has revealed a property of the HSF not previously recognized. The HSF sedimentation was markedly accelerated in the presence of human serum macroglobulin and hog thyroglobulin. The absence of gross detectable changes in the protein profiles after the displacement of the HSF by sedimentation suggests the need for studies on the chemical composition of the HSF.The affinity of the HSF towards the foreign proteins, particularly those of large molecular size, has suggested a useful model by which the relationship of the HSF to other biological activities of B. pertussis may be studied.
Bactericidal antibody studies in maternal serum, colostrum, and newborn serum of the pig
Authors: Webb Phyllis M. , Muschel Louis H.
Published: February 2010

The development of natural bactericidal antibody levels in the piglet was studied and bactericidal antibody levels in newborn serum, maternal serum, and colostrum of the pig were determined. Natural bactericidal antibody levels in serum of the newborn piglet before ingestion of colostrum were extremely low and, as in adult serum, dependent upon natural antibody and complement for its activity. When the animals were 1 year old, large variations in natural antibody levels were found in those of a single litter. The levels of natural antibody in maternal serum, colostrum, and precolostral newborn serum did not reveal a positive correlation. Finally, immunization of gilts before delivery provided a very effective antigenic stimulus in the piglets whose antibody titer, when the animals were 2 weeks old, was comparable to that of the immunized parent.
Lysogeny in mycobacteria. I. Conversion of colony morphology, nitrate reductase activity, and Tween 80 hydrolysis of Mycobacterium sp. ATCC 607 associated with lysogeny
Authors: Jones Wilbur , White Arthur
Published: February 2010

Colony changes from rough to smooth were observed in a rough strain of mycobacterium ATCC 607 after exposure to phages D29 and B4. The colonies surviving after exposure to these two phages were both smooth and lysogenic. Increased nitrate reductase and Tween 80 hydrolytic activities accompanied lysogenization. Loss of lysogeny was accompanied by conversion to the rough colony type and a decrease in nitrate reductase and Tween 80 hydrolytic activities. The rapid loss and gain of these multiple characteristics suggested that the genetic control lies in a plasmid of mycobacteria.
Conversion of phenylalanine to tyrosine by microorganisms
Authors: Chandra P. , Vining L. C.
Published: February 2010

Fourteen microorganisms of different genera were examined for their ability to convert L-phenylalanine directly to tyrosine. Comparison of the specific activities of phenylalanine, tyrosine, aspartic acid, and glutamic acid isolated after hydrolysis of cells grown in the presence of L-phenylalanine-U-14C indicated that p-hydroxylation of phenylalanine had occurred in all seven species of microfungi tested, and in the marine bacterium, Pseudomonas atlantica. In two basidiomycetes, two yeasts, an actinomycete, and a bacillus, there was no preferential incorporation of radioactivity into tyrosine.
Factors influencing tartrate uptake by Penicillium charlesii
Authors: Klatt K. P. , Gander J. E.
Published: February 2010

The uptake of tartrate by P. charlesii has been studied for cultures that were either aerated by shaking or were kept stationary. Stationary cultures were permeable to tartrate when high concentrations of NH4+ (above 36 mM) and glucose (278 mM) were present. Manganous ion (10−5 M) was required for the uptake of tartrate by stationary cultures containing high concentrations of NH4+. Both stationary and shake cultures were able to remove tartrate from the medium when the glucose concentration was reduced below 278 mM; the process was then no longer dependent upon the presence of Mn2+. The influence of changes in the concentrations of glucose and NH4+ was not related to the biochemical events of spore germination.
The production of indolelactic acid from L-tryptophan by species of Phytophthora
Authors: Leal J. A. , Lilly V. G. , Gallegly M. E.
Published: February 2010

Isolates of Phytophthora cactorum, P. citricola, P. cryptogea, P. heveae, and P. syringae produced indolelactic acid (ILA) when cultured on a D-glucose-L-tryptophan medium. The toxicity of ILA for an isolate of P. heveae increased as the pH of the culture medium decreased. When sodium succinate or CaCO3 was added to the medium more mycelium was produced and the pH of the medium did not decrease as much as in the control medium. The value of L-tryptophan as a nitrogen source differed for the various isolates of Phytophthora tested.