bluuebunny/crossref_metadata_2025 huggingface dataset:
THE LOCATION OF THE MUCOPEPTIDE IN SECTIONS OF THE CELL WALL OF ESCHERICHIA COLI AND OTHER GRAM-NEGATIVE BACTERIA
Authors: Murray R. G. E. , Steed Pamela , Elson H. E.
Published: February 2010

Electron micrographs of sections of Escherichia coli have shown that the wall has an extra component 20–30 Å in thickness on the inside of the usual double-track profile. Demonstration was aided by treating the sections with uranium, lanthanum, thallium, or lead salts. This innermost layer alone was lost in spheroplasts produced by penicillin poisoning or treatment with lysozyme-EDTA, and was removed from isolated cell walls by lysozyme. The innermost layer is considered, therefore, to contain the mucopeptide characteristic of bacteria. The inner taut layer (or "intermediate layer") of Spirillum serpens, Vitreoscilla sp., and Simonsiella sp. was also found to be lysozyme sensitive. In the latter species this layer was the sole component of the septum, so that the outer cell wall components enclosed the elements of the trichoma. Other components were less easily localized but it was considered that the lipoprotein layer was outside of the limits of the wall profile usually visualized in sections. The outer layers generally loosened during embedding, but in E. coli and some others the layers all stayed tightly adherent to each other. The Gram-negative bacteria seem to have the double-track layer and the mucopeptide as a basic complement for the cell wall.
STUDIES ON THE BIOLOGICAL STABILIZATION OF THIN STILLAGE: I. AEROBIC FERMENTATION
Authors: Smith R. E. , Fargey T. R.
Published: February 2010

Thin stillage was subjected to aerobic fermentation in both batch and semi-continuous studies, involving forced aeration, sedimentation, and recirculation through a modified trickling filter. The authors have demonstrated that the total solids content and chemical oxygen demand of thin stillage can be reduced considerably by the use of these combined techniques.
THE FINE STRUCTURE OF THIOPLOCA INGRICA AND A COMPARISON WITH BEGGIATOA
Authors: Maier S. , Murray R. G. E.
Published: February 2010

Electron micrographs of sections of Thioploca ingrica and of Beggiatoa showed that the wall of both consisted of multiple and similar layers, of which only the innermost took part in septum formation. Thioploca, however, contained an additional wall component. Invaginations of the cytoplasmic membrane produced extensive intracytoplasmic membranes in both organisms. Sulfur appeared to be deposited within this membrane system, which was accentuated in Thioploca by an enclosure of dense, vesicular material. The deposition of sulfur external (in effect) to the cytoplasmic membrane was also found when hydrogen sulfide and air were bubbled through cultures of a number of Gram-negative bacteria not considered to be sulfur bacteria. The cytoplasm of Beggiatoa was richer in ribosomes than the extraordinarily dense cytoplasm of Thioploca, and the lipid deposits of both left behind spaces that were not membrane-bounded. Metachromatic granules were observed only in Beggiatoa. A heterotrophic strain of Beggiatoa contained a diffuse nucleoplasm, but nucleoplasms could not be recognized either in the wild type or in Thioploca. Thioploca and Beggiatoa are sufficiently different in their infrastructure to be considered distinct organisms. The former consistently produce sheaths. Similarities in structure and in the arrangement of components are enough to support a family relationship.
INFLUENCE OF HUMIDITY ON THE MIGRATION OF BACTERIA ON CUCUMBER SEEDLINGS
Authors: Leben Curt
Published: February 2010

Bacteria carried by cucumber seeds did not appear to migrate to the aerial parts of seedlings under conditions of low humidity (30–40% RH), as determined by imprinting seedling parts in agar. At a high RH (> 90%), however, a yellow resident (isolate A180) added to seed, and bacteria carried naturally by the seed (control residents), migrated to all aerial parts. At an intermediate RH (70–80%), control residents were on all parts, and in addition, A180 consistently was in limited areas. A period of several days of low RH prevented further migration. Stained bacterial cells on the leaf surface were observed in depressions between epidermal cells and on the basal parts of hairs of plants from the high RH; they were sparse at the intermediate RH level and not detected at the low level.
PRODUCTION OF GIBBERELLIN-LIKE SUBSTANCES BY BACTERIA AND ACTINOMYCETES
Authors: Katznelson H. , Cole Shirley E.
Published: February 2010

The production of gibberellin-like substances by bacteria and actinomycetes was investigated. Most of the bacterial cultures tested produced a gibberellic acid-like substance (A3) in amounts varying from 1 to 14 μg/liter. The production of a gibberellin-A9-like compound was much more limited, 6 out of 15 cultures yielding small amounts. Six out of 11 actinomycetes showed evidence of A3 synthesis; two produced A9. Antigibberellin substances co-chromatographing with A3 were detected in culture filtrates of Bacillus polymyxa and two actionmycetes. Cultural conditions and concentration of the ingredients of the medium influenced gibberellin synthesis by Agrobacterium radiobacter. Production of these substances was not growth linked and none was detected in stationary cultures. Microbial synthesis of the gibberellins was demonstrated also by means of assays with the dwarf maize mutants d1, d2, and d5.As added to soil was rapidly inactivated and it was postulated that the plant could derive maximum benefit from microbial synthesis of gibberellins and related substances only at the root surface—the rhizoplane.
THE PRODUCTION OF SPHEROPLASTS BY RAPID-GROWING NON-VIRULENT MYCOBACTERIA
Authors: Sato H. , Diena B. B. , Greenberg L.
Published: February 2010

Spheroplasts were produced in five strains of rapid-growing non-virulent mycobacteria in a variety of media. Optimal spheroplast production occurred after 8–10 days of incubation in the presence of glycine and lysozyme, but in no culture was there complete formation of spheroplasts. While the pattern of spheroplast induction appeared to be specific for each strain and to be highly reproducible, the mechanism of the induction process is unknown.
THE EFFECT OF "COMPETASE" ON DNA UPTAKE IN PROVOKED TRANSFORMATION OF A STREPTOCOCCUS
Authors: Pakula R. , Hauschild A. H. W.
Published: February 2010

The competence-provoking factor produced by the highly transformable group H streptococcus, strain Challis, was used to provoke efficient transformability in the poorly transformable group H streptococcus, strain Wicky. Transformations to streptomycin resistance were carried out with C14-labelled DNA which was extracted from bacteria fed with thymidine-2-C14.When cultures of strain Wicky were grown in Difco brain–heart infusion broth, supplemented with serum, and treated with competence factor and deoxyribonucleic acid, 25 to 40% of viable units were transformed while no transformation occurred without the factor. At the same time, the incorporation of C14into cells treated with competence factor was higher than incorporation of C14into untreated cells.Crude preparations of the competence factor had a retarding effect on growth of the streptococcus, irrespective of whether DNA was added.
A RAPID METHOD FOR MEASURING ANTIBIOTIC SENSITIVITY OF BACTERIA
Authors: Mahony D. E. , Chadwick P.
Published: February 2010

A rapid antibiotic sensitivity test is described in which the criterion of sensitivity was the inhibition of microcolony formation on the surface of agar plates containing antibiotic. Results of the tests were available 4 hours after inoculation of the plates. Comparison between 4-hour microcolony readings and confirmatory observations after 20 hours incubation showed a discrepancy rate of 2.72%. The results obtained by the microcolony method showed a good correlation with those given by the paper disc method. Correlation with the tube dilution method was not so good, but there may be valid reasons for this. The merits and demerits of the microcolony method are discussed.
INFECTIVITÉ ET PROPRIÉTÉ HÉMAGGLUTINANTE DU VIRUS INFLUENZA TRAITÉ À DIFFÉRENTS pH
Authors: Chagnon André , Gilker Jean-Claude , Boudreault Armand
Published: February 2010

The infectivity and hemagglutination titers of influenza viruses were studied after treatment at different pH values during 4 hours at 37 °C.Influenza viruses appeared to be acid-labile. The loss of infectivity of influenza viruses varied within each type, since strains of type B were more labile than those of type A. Moreover, it appeared clearly that equine influenza virus is more resistant to acid than human strains.The acid pH alters more readily the hemagglutinating activity of influenza virus than its infectivity. These experiments would imply that at first there is a rapid destruction of surface protein complexes followed by a less rapid denaturation of nucleoproteins.
AN ANTIVIRAL SUBSTANCE FROM PENICILLIUM CYANEO-FULVUM BIOURGE: II. BIOLOGICAL ACTIVITIES AGAINST RNA-CONTAINING VIRUSES
Authors: Cooke Patricia M. , Stevenson J. W.
Published: February 2010

An antiviral substance produced by Penicillium cyaneo-ffulvum Biourge prevents or markedly reduces the infectivity of influenza virus when the two are mixed and inoculated into embryonated eggs, modified Maitland cultures, monkey kidney cell cultures, or mice. It also inhibits mumps and poliomyelitis viruses in embryonated eggs and monkey kidney cell cultures respectively. The effect of influenza virus toxin on HeLa cells is neutralized.
INTERACTION BETWEEN ESCHERICHIA COLI AND PSEUDOMONAS AERUGINOSA IN MIXED CULTURES
Authors: Guthrie R. K. , Cooper B. H. , Ferguson J. K. , Allen H. E.
Published: February 2010

Both continuous and stationary cultures were used to detect interactions between Escherichia coli and Pseudomonas aeruginosa in mixed cultures, with pure cultures included as controls. The interactions observed were both pH and substrate dependent. Stimulation of P. aeruginosa in mixture was the most marked interaction, and was, in part, due to changes in carbohydrate metabolism.
A STUDY OF THE NUTRITIONAL REQUIREMENTS AND TOXIN PRODUCTION OF CLOSTRIDIUM BOTULINUM TYPE F
Authors: Holdeman Lillian V. , Smith Louis Ds.
Published: February 2010

Clostridium botulinum type F was grown in a chemically defined medium containing 17 amino acids, 11 vitamins, glucose, and inorganic salts. The nutritional requirements were determined using single-omission test media. Arginine, tryptophan, tyrosine, valine, biotin, thiamin, and possibly methionine were essential nutrients. Growth was stimulated by glycine, isoleucine, phenylalanine, and para-aminobenzoic acid. Toxin was present in supernatant fluids from all synthetic medium cultures in which there was marked growth. In general, toxicity of synthetic medium cultures was about 1/10 that of complex medium cultures.Toxin and precursor appear to be formed intracellularly, for both were released by rupturing young cells with sonic vibration. Protoxin could be activated by treatment with trypsin.
ENERGY METABOLISM OF PHYCOMYCES BLAKESLEEANUS THE CITRIC ACID CYCLE AND ASSOCIATED AMINO ACIDS
Authors: Gangloff Edwin C.
Published: February 2010

All of the intermediates of the citric acid cycle are shown to be present in the mycelium of 6-day cultures of P. blakesleeanus grown on glucose and on ammonium sulfate, and fed non-radioactive acetate on the fourth and fifth days and acetate-1-C14on the fifth day of incubation.The concentration of organic acids and certain amino acids, and their specific activity is reported. The high activity of the latter is thought to indicate the presence of a highly labeled pool of nitrogen compounds persisting from the early anabolic reactions after acetate-1-C14administration.
AN APPRAISAL OF THE BENTONITE FLOCCULATION TEST IN THE IMMUNE RESPONSE TO TYPHOID VACCINES
Authors: Wallace R. , Diena B. B. , Greenberg L.
Published: February 2010

Bentonite particles can be sensitized by both somatic O and H (flagellar) soluble antigens. After fixation, washing will remove the unadsorbed O antigen, and also partially elute the flagellar antigen.The serological response of rabbits to immunization with typhoid vaccines was compared by Widal bacterial agglutination and by bentonite flocculation. Bentonite had a limited ability to react with early type antibody, but matched the sensitivity of Widal aggultination for secondary response agglutinins. While bentonite particles are preferentially clumped by secondary response antisera, both mercaptoethanol resistant (7S) and mercaptoethanol-sensitive (19S) antibodies are responsible for bentonite flocculation.
CONVERSION OF GLUTAMIC ACID TO VOLATILE ACIDS BY MICROCOCCUS AEROGENES
Authors: Horler D. F. , Westlake D. W. S. , McConnell W. B.
Published: February 2010

Radiotracer studies confirm that the major products of glutamic acid metabolism by Micrococcus aerogenes are acetic acid, butyric acid, and carbon dioxide. When glutamic acid-1-C14was used as tracer the carboxyl carbons of both acetic and butyric acid were highly radioactive. Carbon 3 of butyric acid also contained some carbon-14. Glutamic acid-2-C14yielded acetic and butyric acid, both of which were highly labelled in carbon 2; carbon 4 of the butyric acid containing some carbon-14. All positions of acetic and butyric acid contained radioactivity when glutamic acid-3, 4-C14was used but carbons 3 and 4 of butyrate were much more highly labelled than carbons 1 and 2. Glutamic acid-5-C14was the only source of radioactive carbon dioxide.The data suggest that some of the butyric acid was derived from the intact four-carbon sequence which constitutes carbons 1, 2, 3, and 4 of glutamic acid and therefore, a pathway of glutamic acid degradation hitherto not recognized must occur in M. aerogenes.
THE ISOLATION OF PULCHERRIMINIC ACID FROM MICROCOCCUS VIOLAGABRIELLAE
Authors: MacDonald J. C.
Published: February 2010

The production of pigmented cells of Micrococcus violagabriellae grown in shake cultures was studied. Pulcherriminic acid was isolated from the pigment and characterized. It was concluded that the insoluble red pigment obtained from the cells was pulcherrimin, identical with the pigment of Candida pulcherrima.
A DEFINED MEDIUM FOR GROWTH AND PIGMENT SYNTHESIS OF MICROCOCCUS ROSEUS
Authors: Cooney J. J. , Thierry O. C.
Published: February 2010

A defined medium has been developed which supports good growth and pigment synthesis of Micrococcus roseus ATCC 516. The medium contains fructose, adenine, alanine, arginine, glutamic acid, glycine, isoleucine, methionine, proline, serine, and inorganic salts. The medium is not a minimal medium, but omission of any component decreases growth or pigment content, or both. Pigment synthesis parallels culture development. Addition of leucine or mevalonic acid decreases pigment content. Diphenylamine (10−7 M) decreases pigment content 27%, suggesting that the carotenoids are principally xanthophylls. Absorption spectra of extracted pigments differ when glucose or fructose is the carbon source, and when fructose-containing medium is supplemented with mevalonic acid.
FURTHER ANALYSIS OF THE REACTION OF PARAMECIUM TO CIGARETTE PAPER ASH SOLUTIONS
Authors: Wang H.
Published: February 2010

The reaction of Paramecium caudatum to solutions containing the ash of cigarette paper was consistent with the response of Paramecium aurelia previously reported. After this confirmation, both these species of Paramecium were used as test organisms during a search for the causative agents for the "Paramecium reaction". A qualitative spectrochemical analysis of cigarette paper ash showed that its chief constituent is calcium (97%) with 12 other detected elements present at levels too low to elicit any response from paramecia. Hydroxyl ions in concentrations equivalent to 0.001 M Ca(OH)2, 0.0008 M KOH, or 0.002 M NaOH simulated but did not duplicate the effect of standard cigarette paper ash solution (as of one cigarette paper in 20 ml water). While neutralization caused the three hydroxide solutions to lose their toxicity, the toxicity of cigarette paper ash solution was not appreciably affected by neutralization. Equivalent solutions of facial tissue, filter paper, and a paper towel, burned the same way as cigarette paper, were used as controls. Each of them affected paramecia differently and none simulated the Paramecium reaction. Further, a comparison between ashes from a paperless cigarette, a whole cigarette, and one with two extra roll-your-own wrappers demonstrated a dependence of the Paramecium reaction on cigarette paper ash as well as a direct correlation between the reaction intensity and the amount of cigarette paper ash present.
DL-S-TRIFLUOROMETHYLHOMOCYSTEINE, A NOVEL INHIBITOR OF MICROBIAL GROWTH
Authors: Zygmunt Walter A. , Tavormina Peter A.
Published: February 2010

DL-S-Trifluoromethylhomocysteine was tested for its effect on the growth of a wide variety of microorganisms. The compound, trifluoromethylhomocysteine, markedly inhibited growth of Mycobacterium smegmatis, Mycobacterium phlei, Candida lipolytica, Saccharomyces cerevisiae, Geotrichum candidum, and to a lesser extent, Candida albicans and Escherichia coli. In M. smegmatis, glutamine, methionine, norleucine, norvaline, and certain natural products reversed this antagonism. Utilization of DL-methionine by Leuconostoc mesenteroides, a culture which requires preformed methionine, was not inhibited by trifluoromethylhomocysteine. The compound was also inactive as a replacement for methionine in growth of L. mesenteroides.
EVALUATION OF ACRIDINE ORANGE FLUORESCENCE TEST IN VIABILITY STUDIES ON ESCHERICHIA COLI
Authors: Korgaonkar K. S. , Ranade S. S.
Published: February 2010

Cultures of Escherichia coli subjected to various treatments were studied for their viability loss, as well as for the changes in fluorescent response on staining with the fluorochrome acridine orange. The treatments employed were irradiation with gamma rays (two different dose rates), beta rays, and ultraviolet rays; thermal shock; thymine starvation; and streptomycin inhibition. Marked deviations from "Strugger effect" are seen. The differences in response observed at different dose rates of irradiation are discussed.
CELLULAR PROTEOLYTIC ENZYMES OF PENICILLIUM CYANEO-FULVUM
Authors: Hill P. , Martin S. M.
Published: February 2010

Soluble cellular fractions of surface and submerged cultures of Penicillium cyaneo-fulvum, grown in beef heart infusion (BHI) medium supplemented with glucose, showed well-defined fluctuations in proteolytic activity. Four proteases were shown to occur in the cells, and fluctuations in protease specific activity were considered to be related to the appearance and disappearance of individual enzymes. Synthesis of these enzymes seemed to be regulated by the pH of the external medium.Several proteases also occurred in filtrates of cultures grown in BHI–glucose medium. A comparison of intra- and extra-cellular alkaline proteases (optima, pH 10) showed that, although they were similar in many respects, the enzymes could be distinguished by their action on polyamino acids. Inability to detect the extracellular alkaline protease in cell preparations suggested that this enzyme was released into the medium as rapidly as it was produced.
FURTHER STUDIES ON THE ANTIGENS OF ESCHERICHIA COLI O26:B6
Authors: McDade Joseph E. , Bailey W. Robert
Published: February 2010

The effect of heat on the O and B antigens of Escherichia coli serotype O26:B6 was studied. Aliquots of cell suspensions containing 1.5 × 1010 cells/ml were heated at 55, 65, 75, 85, and 100 °C, respectively, for 1 hour. The heated cells were centrifuged and the precipitinogen titer determined using O and OB antisera. The supernatants from cell suspensions heated at the higher temperatures contained proportionately more of the soluble antigen than those heated at the lower temperatures.Gel diffusion tests of the supernatants showed that both O and B antigens were released when cells were heated. Mild acid hydrolysis of a supernatant increased the B reactivity of that supernatant and slightly enhanced the O reaction. It was concluded from this study that the O and B antigens exist as a molecular complex; heating releases the B component from the complex and causes the increased agglutination with O antiserum.
THE INTERACTION OF GUANOFURACIN AND LISTERIA MONOCYTOGENES
Authors: Murray E. G. D. , Ghosh B. K. , Murray R. G. E.
Published: February 2010

Guanofuracin, a nitrofuran compound used for the selective enrichment of Listeria monocytogenes, was observed to be inactivated by cultures of L. monocytogenes. L. monocytogenes, in mixed culture, appeared to protect other organisms from the inhibiting action. Supernatant fluids of L. monocytogenes cultures inactivated guanofuracin to a great extent, but neutralization to pH 7.2 removed this activity. No specific guanofuraein-inactivating substance could be detected in L. monocytogenes cultures, Autoclaving (20 minutes at 121 °C) caused partial (60%) destruction of the drug. The antibacterial activity of guanofuracin largely depended upon the pH of the incubation medium, being high in alkaline pH and low in acidic pH. The inactivation in acidic pH can be reversed by adjusting the pH to the alkaline side. The presence of the drug in the medium caused a prolongation of the lag phase but no change in the rate of growth, once established. L. monocytogenes rapidly developed resistance to guanofuracin in proportion to the concentration to which the organism was exposed.
THE DEVELOPMENT OF A CYTOPLASMIC POLYHEDROSIS VIRUS IN THE SPRUCE BUDWORM, CHORISTONEURA FUMIFERANA (CLEMENS)
Authors: Bird F. T.
Published: February 2010

Virus particles and polyhedra develop in patches of viroplasm in the cytoplasm of mid-gut cells of larvae of the spruce bud worm, Choristoneura fumiferana (Clemens). Normal components of the cell disintegrate as the disease spreads, and either they completely disappear or mitochondria, ribosomes, and other components form rings in the outer regions of the cell.Polyhedra develop from dense material which appears to attract and envelop virus particles. Only complete particles with large prominent cores are incorporated into growing polyhedra. As the polyhedra mature, they assume a smooth outline and polyhedral shape and either cease to attract virus particles, or their size is limited by the amount of polyhedron protein and numbers of complete virus particles produced in the cell. Although most of the virus particles not incorporated into polyhedra appear incomplete, the large masses of incomplete particles formed in a similar type of disease of another insect were not found in bud worm larvae.
GROWTH INHIBITION OF UNUSUAL STRAINS OF STAPHYLOCOCCUS AUREUS BY LYSOSTAPHIN AND OTHER ANTISTAPHYLOCOCCAL ANTIBIOTICS
Authors: Zygmunt Walter A. , Browder Henry P. , Tavormina Peter A.
Published: February 2010

Sixteen hospital strains of Staphylococcus aureus (all of the recently discovered bacteriophage UC18type important in hospital-acquired infections) were found to be susceptible to lysostaphin at concentrations significantly lower than those observed with eight penicillins, two cephalosporin analogs, or fusidic acid. Three of the strains were sensitive to propicillin and the others were quite resistant to propicillin, ampicillin, and penicillin G. Cephalothin appeared to be more potent than ceporin in inhibiting these strains. Methicillin was the least active of the semisynthetic penicillins tested. Five strains of S. aureus initially isolated as naturally occurring methicillin- and cloxacillin-resistant mutants were found to have lost their resistance, but these cultures, nonetheless, were shown to be fusidic acid resistant. Several "phagocytosis-resistant" strains of S. aureus were observed to be highly susceptible to growth inhibition by lysostaphin and other antistaphylococcal antibiotics.
NEMATOCIDAL ACTIVITY TO PRATYLENCHUS PENETRANS BY CULTURE FLUIDS FROM ACTINOMYCETES AND BACTERIA
Authors: Walker J. T. , Specht C. H. , Bekker J. F.
Published: February 2010

The fluids from cultures of four isolates of Streptomyces sp. and two isolates of Bacillus sp. which were obtained from soil were found to be nematocidal (in vitro) to adults and larvae of Pratylenchus penetrans. Fluids from bacterial cultures were more nematocidal than those from actinomycete cultures, and the degree of activity was dependent upon both temperature and duration of incubation. Approximately 60% mortality resulted with bacterial fluids produced at 10 and 15 C, whereas those produced at 25 C caused 30% mortality. Approximately 40% mortality resulted with fluids produced by actinomycetes at 5, 10, or 15 C, and 15% mortality with those produced at 25 C. Activity was generally independent of the amount of cellular material produced, as greatest growth of the cultures occurred at 25 C.
NUTRITIONAL REQUIREMENTS FOR AUTOPLAQUE PRODUCTION IN AP+ STRAINS OF PSEUDOMONAS AERUGINOSA
Authors: Berk Richard S.
Published: February 2010

The nutritional requirements for the growth of strains of Pseudomonas aeruginosa that produced autoplaques (AP+ strains) with and without the spontaneous production of turbid autoplaques was investigated. Self-lysis was most evident when the organisms were cultivated on complex growth media such as try p tone or brain–heart infusion agar. Partial to complete suppression of self-lysis was most evident when the cultures were grown on blood agar, chocolate agar, Seller"s differential medium, MacConkey, and other dye-containing media. In addition, lysis on a basal medium such as tryptone was suppressed by single supplements of nitrate, nitrite, normal serum, or basic fuchsin. The lytic response of cells grown on tryptone agar was duplicated when L-arginine, L-glutamate, L-glutamine, L-proline, or L-asparagine were singly supplemented to a vitamin-free salts basal medium devoid of a carbon and nitrogen source.
FACTORS AFFECTING PHAGE-RESTRICTING ABILITY IN RHIZOBIUM LEGUMINOSARUM STRAIN L4
Authors: Schwinghamer E. A.
Published: February 2010

Rhizobiophage [Formula: see text] is modified, by growth in Rhizobium leguminosarum strain L25, to the [Formula: see text] form, which has a low plating efficiency on host strain L4. Alteration of plating efficiency (EOP) was used as a means of studying the nature of phage-restricting ability in L4 cells. Mixed infection involving another phage or the unrestricted form of [Formula: see text] as helper phage increased EOP on L4 up to 200-fold, depending on time and sequence of infection. Multiple (cooperative) infection with [Formula: see text] or sublethal heat treatment of cells increased EOP by about 1000-fold. Growth of cells after they were heated resulted in fairly rapid recovery of restricting ability. Ultraviolet light irradiation of cells induced a lower order of EOP enhancement (7- to 10-fold), and loss and recovery of restricting ability appeared to occur more slowly. Some evidence of an interaction between de-restricting treatments was noted for irradiation and multiple infection. Rapid inactivation of the restricted phage genome after injection was indicated in experiments in which de-restricting treatments were applied belatedly after infection. The results and their implications concerning the nature of restricting ability are compared with those of other phage–host systems.
ELECTRON MICROSCOPY OF ULTRATHIN SECTIONS OF MICROCOCCUS CRYOPHILUS
Authors: Mazanec K. , Kocur M. , Martinec T.
Published: February 2010

Ultra thin sections of Micrococcus cryophilus cells were investigated. The cell wall, consisting of several layers, measures 410–500 Å and is covered with a distinct capsule. The cytoplasm, which is of granular structure, includes ribosomes, condensed chromatin, and occasionally mesosomes. The nuclear material has various shapes and is formed by filaments proceeding in various directions. We could find no evidence to bear out the supposition of Kocur and Martinec (1962) that M. cryophilus is related to Micrococcus luteus. M. cryophilus is, in its structure as well as its groupings of cells, different from micrococci, which leads us to believe that it does not belong to the genus Micrococcus.
THE EFFECT OF ACTINOBOLIN ON NUCLEIC ACID AND PROTEIN SYNTHESIS IN ESCHERICHIA COLI
Authors: Hunt D. E. , Pittillo R. F. , Johnson E. P. , Moncrief F. C.
Published: February 2010

Actinobolin inhibits protein synthesis in Escherichia coli. When the antibiotic is added to a culture at the time of inoculation, RNA synthesis is also inhibited. Inhibition of RNA synthesis appears to be a consequence of inhibition of protein synthesis. Cross-resistance experiments suggest that the mechanism of action of actinobolin differs from that of the other inhibitors of protein synthesis, chloramphenicol and sparsomycin. Phenylalanine prevents the action of actinobolin provided the amino acid and antibiotic are added simultaneously; this effect is not observed if the phenylalanine is added 1 hour after the addition of the antibiotic. Evidence is presented that the mechanism by which phenylalanine prevents inhibition by actinobolin differs from that which has been suggested for azaserine and p-fluorophenylalanine.
THE SPHEROPLASTS OF BORDETELLA PERTUSSIS
Authors: Mason M. Aileen
Published: February 2010

The formation of spheroplasts by Bordetella pertussis in fluid medium containing glycine has been demonstrated. The B. pertussis organisms were grown in a fluid medium containing glycine with aeration on a rotary shaker at 35 °C for 40 hours. Maximum spheroplast production was obtained by increasing the basic inoculum 10-fold to 5 × 107 organisms per milliliter.The B. pertussis spheroplasts are large, round, vacuolated cells resembling those described in other Gram-negative species. They are fragile, autolyze readily at pH values of 7.9–8.3, and are more susceptible to mechanical rupture and enzyme attack than are the bacilli.No adaptation of the bacilli to glycine was observed on successive transfer through increasing concentrations of glycine, and the spheroplasts revert to the bacillary form on transfer to a suitable solid or fluid medium.
BIOSYNTHESIS OF PTEROIC-ACID-LIKE MATERIALS BY STAPHYLOCOCCUS EPIDERMIDIS
Authors: Williams F. D. , Koft B. W.
Published: February 2010

Washed resting-cell suspensions of Staphylococcus epidermidis produce considerable quantities of rhizopterin-like materials when incubated with para-aminobenzoic acid (PABA), adenosine triphosphate, MgSO4, and 2-amino-4-hydroxy-6-hydroxymethyldihydropteridine. A number of purine derivatives also stimulate the formation of these same materials, with the combination of inosine and serine proving to be optimal. The stimulation with either the purine or pteridine substrate occurs in two principal products, one identified as rhizopterin and the other a labile material spontaneously forming rhizopterin. The hypothetical formation of these pteroate coenzyme forms in association with the coupling reaction between pteridines and PABA is discussed.
PHYSICOCHEMICAL FACTORS INFLUENCING GROWTH AND PIGMENT SYNTHESIS BY MICROCOCCUS ROSEUS
Authors: Thierry O. C. , Cooney J. J.
Published: February 2010

Growth of and carotenoid synthesis by Micrococcus roseus are optimum at pH 6.8 and pH 7.5 in a defined medium. Maximum growth and pigment content were obtained in aerobic cultures at 25 C. Supplementing the medium with more than 0.2% NaCl resulted in less growth and decreased pigment content per unit mass of cells. At pH 7.5 the absence of visible light had no effect on growth or pigment content, but at pH 6.8 both were decreased in dark-grown cultures. Biotin did not reverse inhibition of growth in the dark. Dark inhibition was reversed by exposure of lag or early log phase cultures to visible light for 30 min, but late log or stationary phase cultures grown in the dark did not respond. Stationary phase dark-grown cultures resumed growth and pigment synthesis during a 24-h period in light. Serial culture in the dark did not result in a further decrease in growth or pigment synthesis; and when cells from serial cultures grown in darkness were used as inoculum for cultures grown in the light, maximum growth and pigment synthesis occurred. These data suggest that light is required for induction of maximum growth and pigment synthesis. A crude action spectrum was determined and suggests that light in the range from 625 to 700 mμ may be responsible for photoinduction.None of the environmental variations altered the absorption spectrum of pigment extracts. Conditions which were optimum for growth were also optimum for pigment synthesis.
ADAPTATION OF THE SOIL MICROBIOTA TO HIGH CO2 AND LOW O2 TENSIONS
Authors: Stotzky G. , Goos R. D.
Published: February 2010

The ability of the soil microbiota to adapt to atmospheres of high CO2 and low O2 tensions was investigated. Subsamples of soil were incubated (conditioned) in gases containing different concentrations of CO2 and O2, and the tolerance to adverse atmospheric conditions of organisms subsequently isolated was compared with that of organisms present in the soil before conditioning. Although apparent adaptation of the fungal, bacterial, and actinomycete populations occurred, it was not established whether physiological adaptation, rather than enrichment of segments within the populations tolerant to these conditions, occurred. Adaptation appeared to be enhanced by conditioning the soil in gases similar to, but not the same as, that under which the organisms were subsequently isolated. Although adaptation, in general, increased as the CO2 tension of the conditioning atmospheres decreased, the CO2 concentration, rather than reduced O2 tensions, induced adaptation. Aspergillus, Fusarium, Penicillium, and Trichoderma exhibited greater tolerance and adaptability to high CO2 and low O2 tensions than other genera of the mycobiota. Possible implications of the capacity to adapt to adverse atmospheric conditions in the ecology of microorganisms in soil are discussed.
THE NON-SPHERULITIC BIREFRINGENCE IN CELLULOSE PELLICLES OF ACETOBACTER XYLINUM
Authors: Colvin J. Ross
Published: February 2010

The development of non-spherulitic, threadlike birefringence, observable in pellicles of bacterial cellulose from Acetobacter xylinum, is described. This birefringence is a consequence of the formation of bundles of parallel cellulose microfibrils within the pellicle. The reason for this parallel orientation is unknown and all attempts to influence it have failed. The development of the birefringent threads within the pellicle is often accompanied by formation of streaks of lipid-like material Boating on the surface of the medium. The distribution of these streaks is similar to the distribution of the non-spherulitic birefringence. This similarity in distribution may be a reflection of a common origin.
HISTOCHEMICAL CHANGES IN MELOLONTHA MELOLONTHA (LINNAEUS) (COLEOPTERA) INFECTED BY A NEW VIRUS
Authors: Morris Oswald N.
Published: February 2010

Changes in DNA, RNA, protein, and glycogen in the fat body of a beetle, Melolontha melolontha (Linnaeus), were studied histochemically at intervals of 15, 23, 75, and 195 days after intrahemocoelic injection of a cytoplasmic polyhedrosis virus, Vagoiavirus melolonthae. As the disease progressed, the average nuclear diameter increased considerably without any apparent change in DNA content. Cytoplasmic RNA increased progressively for about 75 days and then decreased slightly. Nuclear protein content increased during the first 23 days after virus inoculation. Cytoplasmic protein content progressively increased throughout the disease process. There was no significant change in glycogen reserves 23 days after inoculation; thereafter, glycogen was drastically reduced.Three morphologically different types of cytoplasmic inclusions all staining intensely with naphthol yellow S (thus establishing their proteinaceous nature) were observed. The pyroninophilic "round" type is considered to be "mature" inclusions containing the virus particles demonstrated by electron microscopy. The resemblances between this virus and some viruses of higher animals are discussed.
CO-TRANSDUCTION OF THE GENETIC DETERMINANTS OF SYNTHESIS OF PENICILLINASE AND METHIONINE IN STAPHYLOCOCCUS AUREUS
Authors: Harmon Shirley A. , Baldwin Jack N. , Tien Wei-chen , Critz Doris B.
Published: February 2010

Six penicillin-sensitive, methionine-dependent mutants of Staphylococcus aureus were competent recipients of the genetic determinants of penicillinase production and methionine synthesis. Co-transduction of the two characteristics was observed. Transductional analyses indicated that there was a close association between the extrachromosomal determinant of penicillinase production and the locus controlling the formation of cystathionine. Based on the experimental evidence, it was concluded that the penicillinase determinant may be an episome.
THE ACCUMULATION OF α-KETOGLUTARATE BY SUSPENSIONS OF PSEUDOMONAS AERUGINOSA
Authors: Tigerstrom Margaret von , Campbell J. J. R.
Published: February 2010

Pyruvic and α-ketoglutaric acids accumulated during the oxidation of glucose by washed cell suspensions of Pseudomonas aeruginosa harvested from a glucose medium. The addition of ammonium salts had been shown to prevent the accumulation of the α-ketoglutaric acid in such suspensions. A similar situation was shown to exist with growing cultures. The accumulation of α-ketoglutaric acid was not due to inability of the cells to synthesize enzymes required for the oxidation of this compound. Cells harvested from a glucose medium required an induction period before oxidizing α-ketoglutaric acid but this was apparently due to the lack of a permease required for the transport of the substrate across the cell membrane. A comparison of the enzyme levels of cell extracts prepared from cells grown on a glucose medium with those grown on an α-ketoglutaric acid medium revealed that the latter had a higher level of the individual apoenzymes required for α-ketoglutaric acid oxidation. However, the apoenzyme level of the extracts of glucose-grown cells appeared adequate to prevent the accumulation of α-ketoglutaric acid during glucose oxidation.It is concluded that during growth in the presence of an excess of ammonium salts α-ketoglutarate never escapes from the internal metabolic pool of the cells and therefore the permease for α-ketoglutarate is not synthesized. During glucose oxidation by washed suspensions of glucose-grown cells, α-ketoglutarate is perhaps excreted from the cell either because the cells are deficient in the coenzymes necessary for α-ketoglutarate oxidation or because the avidity of the enzymes for substrate is such that, at low levels of substrate, the enzymes of α-ketoglutarate oxidation act so slowly that the intermediate accumulates.
FORMATION OF POLYTHIONATES AND THEIR INTERRELATIONSHIPS DURING OXIDATION OF THIOSULFATE BY THIOBACILLUS FERROOXIDANS
Authors: Sinha D. B. , Walden C. C.
Published: February 2010

The metabolic pathway for the utilization of thiosulfate by the acidophilic chemoautotroph, Thiobacillus ferrooxidans, has been examined by chromatographic and radiographic techniques. With suitable chemical controls, it was found that the major pathway involved 2 moles of thiosulfate passing to tetrathionate to trithionate regenerating 1 mole of thiosulfate concurrent with the production of 2 moles of sulfate. Thus, previous findings which demonstrate this pathway as far as trithionate, made with other thiobacilli, are sound despite recent documentation of the chemical interaction of various polythionates. The cyclical pathway, proposed here, explains some findings of other workers.
STIMULATION OF BACTERIA AND ACTINOMYCETES BY THE POLYENE ANTIBIOTIC PIMARICIN IN SOIL DILUTION PLATES
Authors: Tsao Peter H. , Thieleke David W.
Published: February 2010

Fungi were inhibited and numbers of colonies of bacteria and actinomycetes increased in soil dilution plates of agar media containing 100 p.p.m. pimaricin when compared with the same media without pimaricin. The increase in bacteria and actinomycetes was a result of stimulation by the antibiotic rather than the absence of antagonistic fungi in the antibiotic media. The chemically related antifungal polyene antibiotic, nystatin, produced similar results.
INHIBITION OF GROWTH OF PSEUDOMONAS DENITRIFICANS BY AMINO ACIDS
Authors: Daniels Horace J.
Published: February 2010

A large number of amino acids failed to support growth of Pseudomonas denitrificans in a basal medium composed of glucose, ammonium phosphate, and other mineral salts. Inability of an amino acid to support growth correlated well with its inhibitory action in a complete medium made up by adding L-glutamic acid to the basal medium. D-Amino acids were more toxic than the corresponding L-forms, and neutral amino acids were more toxic than acidic amino acids. Basic amino acids which were least toxic supported the best growth. The danger of the indiscriminate use of amino acid mixtures for culture studies is discussed.
DNA BASE COMPOSITION OF CYTOPHAGA MARINOFLAVA N. SP. DETERMINED BY BUOYANT DENSITY MEASUREMENTS IN CESIUM CHLORIDE
Authors: Colwell R. R. , Citarella R. V. , Chen P. K.
Published: February 2010

A marine bacterium, NCMB 397, host strain for bacteriophages NCMB 384 and 385, has been subjected to taxonoinic analysis. Overall base composition of the highly purified deoxyribonucleic acid was determined and found to be 37 moles % guanine + cytosine. The phenetic and nucleic acid data suggest significant relationship of this strain and members of the genus Cytophaga. A description of Cytophaga marinoflava n. sp. is presented.
THE EXCLUSION OF INTRACELLULAR LAMBDA FROM ESCHERICHIA COLI Y10 (λ) BY T4r+ COLIPHAGE
Authors: French R. C. , Barrens M.
Published: February 2010

The exclusion of lambda development in induced Y10 (λ) by infection with T4r+ was examined. The slow rate of adsorption of phage to cells was improved by propagation of the bacteria in nutrient broth containing glucose. Under conditions of satisfactory adsorption, it was found that T4 and ultraviolet irradiated T4 nearly completely excluded lambda when added to induced cells as late as 30 minutes after induction. Less than 2% of the induced cells were refractory to T4 infection. By 50 minutes after induction T4 still excluded lambda from 50% of the cells, but by 70 minutes most of the cells were committed to the production of lambda.
PERMEABILITY OF A MICROCOCCAL CELL TO MALTOSE AND SOME RELATED SUGARS
Authors: Williams P. J. le B. , McDonald I. J.
Published: February 2010

Cells of Micrococcus sp. ATCC No. 407 grown in glutamic acid medium were permeable to maltose, maltotriose, maltotetraose, maltopentaose, 3-ketomaltose, and β-methylmaltoside but not to glucose, α-methylglucoside, isomaltose, maltitol, cellobiose, sucrose, trehalose, or lactose. The results suggest that the uptake mechanism is constitutive and may be specific for sugars with α,1–4 linkages. The kinetics of maltose and maltotriose uptake are in accord with the sugars undergoing an initial combination with a site followed by a rate-limiting reaction. Maltotriose competitively inhibited maltose uptake, which suggests that the same site is used during uptake of these two sugars. Maltotriose was taken up at a greater rate than maltose, which suggests that the rate-limiting process during uptake is not diffusion but a reaction that proceeds faster with maltotriose than with maltose.
INFLUENCE OF CLAY MINERALS ON MICROORGANISMS: III. EFFECT OF PARTICLE SIZE, CATION EXCHANGE CAPACITY, AND SURFACE AREA ON BACTERIA
Authors: Stotzky G.
Published: February 2010

The stimulation of bacterial respiration by clay minerals was related to certain physicochemical characteristics of clays. Respiration increased with an increase in the cation exchange capacity and surface area of the particles. The importance of surface area, however, could not be unequivocally established, as some of the methods used to determine this characteristic on certain clay species were questionable. Particle size did not appear to be a critical characteristic. The implications of the cation exchange capacity of clay minerals in the activity, ecology, and population dynamics of microorganisms in nature are discussed.
Isolation, selection, and characterization of beneficial rhizobacteria from pea, lentil, and chickpea grown in western Canada
Authors: Hynes Russell K. , Leung Grant C.Y. , Hirkala Danielle L.M. , Nelson Louise M.
Published: February 2010

The use of beneficial soil microorganisms as agricultural inputs for improved crop production requires selection of rhizosphere-competent microorganisms with plant growth-promoting attributes. A collection of 563 bacteria originating from the roots of pea, lentil, and chickpea grown in Saskatchewan was screened for several plant growth-promoting traits, for suppression of legume fungal pathogens, and for plant growth promotion. Siderophore production was detected in 427 isolates (76%), amino-cyclopropane-1-carboxylic acid (ACC) deaminase activity in 29 isolates (5%), and indole production in 38 isolates (7%). Twenty-six isolates (5%) suppressed the growth of Pythium sp. strain p88-p3, 40 isolates (7%) suppressed the growth of Fusarium avenaceum , and 53 isolates (9%) suppressed the growth of Rhizoctonia solani CKP7. Seventeen isolates (3%) promoted canola root elongation in a growth pouch assay, and of these, 4 isolates promoted the growth of lentil and one isolate promoted the growth of pea. Fatty acid profile analysis and 16S rRNA sequencing of smaller subsets of the isolates that were positive for the plant growth-promotion traits tested showed that 39%–42% were members of the Pseudomonadaceae and 36%–42% of the Enterobacteriaceae families. Several of these isolates may have potential for development as biofertilizers or biopesticides for western Canadian legume crops.
Semiselective isolation of the ethanol-imbibing sooty mould Baudoinia of distillery aging warehouses
Authors: Ewaze Juliet O. , Summerbell Richard C. , Scott James A.
Published: February 2010

Baudoinia compniacensis is a darkly pigmented microfungus that grows conspicuously on environmental surfaces around warehouses where alcoholic spirits are stored in wooden casks. This fungus has long been ignored because its primary isolation is very difficult. The present study describes a new semiselective isolation medium for this fungus based on the use of ethanol as a sole carbon source and low levels of nitrogen and trace elements.
Vegetation influences patch occupancy but not settlement and dispersal decisions in a declining migratory songbird
Authors: Harrison M. L. , Green D. J.
Published: February 2010

Territorial clustering within larger, continuous patches of seemingly appropriate habitat could indicate that a species has additional, finer scale habitat requirements. Studying fine-scale (e.g., territory-level) habitat selection using methods that elucidate individual preferences may allow us to identify resources that influence species distributions. We examined breeding territory selection in the sagebrush Brewer’s Sparrow ( Spizella breweri Cassin, 1856) at the northern extent of its range to test for influences on fine-scale habitat selection. We used an information–theoretic approach to evaluate models relating a suite of vegetation characteristics to breeding habitat selection. We employed two methods: (1) assessment of patch occupancy at a territory scale and (2) examination of individual decisions relating to settlement and dispersal. We found that patch occupancy was most consistently predicted by models that included the cover of big sagebrush ( Artemisia tridentata Nutt.) with the greatest likelihood of occupancy at 20%–25% cover. However, assessment of settlement and dispersal decisions did not identify additional fine-scale preferences for other vegetation characteristics. Vegetation cover also did not influence breeding success, indicating that within the vegetation range found in Brewer’s Sparrow territory clusters, there is little benefit in basing individual settlement or dispersal decisions on vegetation cover.