bluuebunny/crossref_metadata_2025 huggingface dataset:
On the nature of the forces involved in the sex-directed flocculation of a fission yeast
Authors: Calleja G. B.
Published: April 2010

Cells of Schizosaccharomyces pombe NCYC 132 flocculate during stationary growth phase. Inducible by aeration, flocculation is followed by conjugation and formation of ascospores. Not all cells in a culture are competent to form flocs. Cells in flocs are separable from the in competent cells by differential sedimentation. Stable when diluted in deionized water, flocs are reversibly deflocculated by heat. Tm, the temperature at which half a floe population is deflocculated, is 61 °C in deionized water. Mono- and di-valent cations increase Tm and the rate of reflocculation at ambient temperature. Guanidinium chloride, urea, sodium dodecyl sulfate, extremes of pH, and ultrasonication also reversibly deflocculate purified flocs. In contrast, proteinases, e.g., pronase and trypsin, cause irreversible deflocculation. All reflocculation exhibits hysteresis. It is very likely that the principal binding forces are hydrogen and hydrophobic bonds between walls of competent cells, rather than ionic bonds. The data also suggest the involvement of some proteinaceous structure on the cell wall.
ICMSF methods studies. V. The influence of selective enrichment media and incubation temperatures on the detection of salmonellae in raw frozen meats
Authors: Silliker J. H. , Gabis D. A.
Published: April 2010

Sixty lots of frozen raw meat were analyzed for Salmonella using preenrichment in lactose broth followed by selective enrichment in four different selective broths, each incubated at 35C and 43C. Incubation at 43C resulted in detection of more Salmonella-containing samples. The highest recovery was observed with selenite cystine at 43C. However, the data indicated that two selective broths should be used for maximum recovery. Tetrathionate broth without brilliant green was inferior to the three other selective media used, both at 35C and 43C. Using selenite cystine, tetrathionate brilliant green, and selenite brilliant green sulfa broths, a number of medium/temperature pairs gave Salmonella recoveries approaching that obtained from all eight medium/temperature variables combined.
The negative staining of "difficult" bacteria like Arthrobacter globiformis for electron microscopy
Authors: Chan E. C. S. , Gomersall M. , Bernier J.
Published: April 2010

A method is suggested for the negative staining of "difficult" bacteria like Arthrobacter globiformis for electron microscopy when the usual procedures do not give satisfactory results. It involves glutaraldehyde fixation, and thorough washing and drying of the cell suspension on a grid sitting on a bed of plain agar, followed by a rapid flushing with 2% phosphotungstic acid.
A new approach to the description of colony color of cytophagas and their allies
Authors: Christensen Penelope J.
Published: April 2010

Descriptive microbiology is in urgent need of more precise definitions of morphological parameters. The introduction of an objective, qualitative system to replace the very subjective and limited naming of colonies is long overdue. A simple method is described by which the color of a bacterial colony can be recorded rapidly and accurately using the Munsell system of color notation. The results of investigations with cytophagas and flavobacteria showed that the method is reliable and reproducible under standard conditions.
Yeasts isolated from some lakes and rivers of Saskatchewan
Authors: Spencer J. F. T. , Gorin P. A. J. , Gardner N. R.
Published: April 2010

Yeasts were isolated from lakes in northern Saskatchewan, from the Saskatchewan River between Prince Albert and Cumberland House, and from three small lakes near Saskatoon, two of which form part of recreational areas. Yeast and bacterial counts were relatively low, less than 400 yeast cells/liter, except in samples taken near towns and industrial plants which discharged waste into the rivers or lakes. There was little change in the numbers of yeast cells in waters used for recreational purposes only, but the number of species isolated increased considerably. Most of the yeasts isolated from the other lakes and rivers were species known to occur in association with trees and in soils.
Aliphatic alcohols and bacterial motile behavior
Authors: Biddle C. , Doetsch R. N.
Published: April 2010

Aliphatic alcohols induced a state of continuous uncoordinated translational movement in Pseudomonas fluorescens, Citrobacter freundii, Alcaligenes faecalis, and Rhodospirillum rubrum. This behavior was reversible and ceased upon removal of the stimulus. A hypothesis based upon electrostatic mechanisms is presented to explain these observations.
Isolation and immunological characterization of a unique toxic cytoplasmic polymer of type 1 Neisseria gonorrhoeae
Authors: Cheng A. , Kwapinski J. B. G. , Ronald A. R.
Published: April 2010

Cytoplasms of types 1 and 4 of Neisseria gonorrhoeae, passed through 0.2-micron (μ) membrane filters, were resolved on Sephadex G-200 columns, followed by repeated isoelectric focusing of peak-zone materials. By each method and by disc electrophoresis, it was found that the type 1 cytoplasm contained one extra component (β). The partly purified, unique biopolymer of type 1 cytoplasm proved to be four times more toxic for chick embryos than was another toxic material found in both cytoplasms. The β compound was identified as a protein that had no immunological counterpart among the remaining cytoplasmic components.
A partially defined medium for the flagellate stage of Tetramitus rostratus
Authors: Brent Morgan M. , Paxton Helene
Published: April 2010

The flagellates of Tetramitus rostratus were grown in a buffered trypticase – yeast extract broth (TY) to which autoclaved Escherichia coli had been added. With the increase of the concentration of trypticase to 1.0%, the yeast extract could be eliminated if replaced with nicotinamide, pyridoxal HCl, folic acid, and thiamine. It was found that the non-dialyzable fraction of sonically disrupted bacteria supported growth and that the activity resided in the bacterial ribosomes. The possible role of the ribosomes is discussed.
Effects of wall inhibitors on thymineless Streptococcus faecalis
Authors: Bisaillon J. G. , Repentigny J. de , Mathieu L. G.
Published: April 2010

Thymine-requiring (thy−) mutants of Streptococcus faecalis and S. faecalis var. zymogenes were isolated by selection with aminopterin. D-Cycloserine increased the thymineless death rate of a S. faecalis thy− strain, whereas bacitracin, penicillin, and vancomycin decreased it. A S. faecalis var. zymogenes thy− strain behaved similarly, except that penicillin increased its thymineless death rate. D-Alanine reversed the effect of D-cycloserine on both strains. Because of the specificity of the inhibition, our observations suggest that mucopeptide synthesis occurs in S. faecalis not only during growth but also during thymineless death. The variations in free amino sugar content resulting from D-cycloserine inhibition of growth and thymineless death also support this conclusion.
Anaerobic sporulation in facultatively anaerobic species of the genus Bacillus
Authors: Couchot Kendra R. , Maier Siegfried
Published: April 2010

Sixteen strains of 11 facultatively anaerobic species of the genus Bacillus were tested for their ability to sporulate anaerobically on common laboratory media. Reliable data depended on a method providing anaerobic conditions quickly. Bacillus macerans (one strain tested) and B. polymyxa (two out of two strains tested) sporulated anaerobically without added nitrate. But B. licheniformis (one out of two strains tested) required nitrate for "anaerobic" sporulation. Anaerobic sporulation of B. macerans and B. polymyxa on potato extract agar was inhibited by nitrate.
Comparison of antiglobulin, direct, and anticomplement immunofluorescent staining for the identification of cytomegalovirus in cultured human fibroblasts
Authors: Laing Allan C.
Published: April 2010

The sequential development of intracellular antigens in cultured human embryonic fibroblasts infected with the AD-169 strain of cytomegalovirus was studied by means of antiglobulin, direct, and anticomplement immunofluorescent staining.Direct immunofluorescent staining, although less sensitive than the antiglobulin or anticomplement methods for the detection of early diffuse nuclear antigens, gave the clearest definition of the typical intracellular inclusions produced by cytomegalovirus.Quantitative complement fixation assays, carried out in parallel with anticomplement staining, showed that complement is fixed strongly by the intracellular antigens which develop in the late stages of infection.
Aerotaxis in Spirillum volutans
Authors: Caraway B. H. , Krieg N. R.
Published: April 2010

Spirillum volutans responded aerotactically to self-created oxygen gradients in capillary tubes. Band formation required an oxidizable substrate, inorganic ions, and a chelating agent. The higher the respiratory rate, the faster the band migrated. Random motility occurred in the anaerobic region behind the band. Inhibitor studies indicated the existence of two alternative energy pathways for motility: one involved the oxidation of exogenous substrates while the other allowed energy production in the absence of oxygen uptake and was apparently linked to intracellular poly-β-hydroxybutyrate breakdown. Respiratory inhibitors such as KCN caused decreases in ATP and prevented band formation but allowed motility. 2,4-Dinitrophenol stimulated oxygen uptake but caused decreases in ATP and prevented band formation. Oxidation of substrates without aeration caused decreases in ATP while aeration increased ATP. Aerotactic band formation therefore appeared to result from an avoiding reaction in which cells moved away from the anaerobic environment created by the band, thereby resulting in an increase of cellular ATP. Results with 2,4-dinitrophenol suggested that not only is oxygen uptake required for band formation but also oxidative phosphorylation. Intracellular ATP levels may possibly serve to regulate the aerotactic response.
Clostridium durum, sp. nov., the predominant organism in a sediment core from the Black Sea
Authors: Smith Louis DS. , Cato Elizabeth P.
Published: April 2010

Microbiological examination of a sediment core from the Black Sea showed 1320 viable organisms per gram at the surface, 630 per gram 5 cm below the surface, 760 per gram at the 10-cm level, and 700 per gram at the 20-cm level, which had been laid down about 400 years ago, according to radiocarbon dating. Many of the isolates belonged to known clostridial species, although most did not. The predominant organism found below the surface was an aerotolerant Clostridium, C.durum, sp. nov.
Toxic properties of Aeromonas proteolytica
Authors: Foster B. G. , Hanna Mary O.
Published: April 2010

Aeromonas proteolytica was grown for various time periods in nutrient broth, tryptic soy broth, a semisynthetic medium, and 1 and 5% peptone under different conditions involving temperature and in continuous shake and stationary flasks. The cell-free culture filtrates were tested for hemolytic, endopeptidase, and dermonecrotic activity and optimal growth conditions for their production were determined. The dermonecrotic activity and endopeptidase activity was found to be parallel in all tests, while hemolysin was independent of the other two. Studies on the thermal stability of the culture filtrate revealed that hemolysin and dermonecrotic and endopeptidase activity were destroyed at 70 °C for 30 min. Fractionation of the filtrate by Sephadex G-200 resolved three peaks at 280 nm. Peak I was inactive; peak II contained endopeptidase and dermonecrotic and hemolytic activity; peak III contained pigment and hemolysin. Evidence is presented that the endopeptidase and dermonecrotic substance found in the cell-free filtrates of A. proteolytica grown medium appear at the same time and thus may be the same entity.
Motility and flagellation of Arthrobacter strains
Authors: Antheunisse J.
Published: April 2010

Motility and flagellation of 120 Arthrobacter strains derived from soil have been studied. About 80% of 95 of the strains, non-motile and non-flagellated, were identified as A. globiformis. No difference was made between A. globiformis and A. pascens. Of the 25 motile strains 60% were identified as A. simplex. The motile strains always showed a mixture of subpolar and peritrichous flagellated cells. The rods of 14 non-chromogenic strains had mainly normal flagella (wavelength 1.8–2.8 μm) while mainly curly (wavelength 1.0–1.8 μm) and undulant flagella were observed on 5 yellow strains. Nearly all of the motile strains demonstrated flagellated cocci after 5 and 11 days. In spite of their flagellation motile cocci were rarely observed.
Decreased activity of colicins K-K235, A-CA31, C-CA57, and E2-CA42 upon sensitive Escherichia coli strains in the presence of cyclic 3′,5′–adenosine monophosphate
Authors: Lavoie M. , Mathieu L. G.
Published: April 2010

The addition of cyclic 3′,5′-adenosine monophosphate (c-AMP) at a final concentration of 3 mM to nutrient broth significantly decreased the lethal activity of crude preparations of colicins A-CA31, K-K235, E2-CA42, and C-CA57 upon three different sensitive Escherichia coli strains. A protective effect of c-AMP on cell viability could also be shown in mixed cultures of the colicinogenic and the sensitive strains. Furthermore, the addition of c-AMP significantly reversed, in the sensitive E. coli ROW strain, the inhibition of triphenyltetrazolium chloride (TTC) reduction caused by the bacteriocins. However, the activities of colicin E3-CA38 on cell viability and reduction of TTC were not overcome markedly by exogenously added c-AMP. None of seven other cyclic nucleotides tested appeared to duplicate the protective effect of c-AMP against colicin A-CA31. The results indicate that for colicins K-K235, A-CA31, C-CA57, and E2-CA42 but not for colicin E3-CA38, there may be similar steps in the translocation of effects to sensitive targets and (or) a closely related mode of action reversible by c-AMP.
Cold-sensitive mutants of the psychrophile Bacillus psychrophilus
Authors: Inniss W. E. , Murray W. D. , Ingraham J. L.
Published: April 2010

Cold-sensitive mutants have been developed from the psychrophile Bacillus psychrophilus. At 5C, when compared with the parental strain, the mutants showed a distinctly different colony morphology and had a decreased capacity to form septa, tending to form elongated cells. However, at 20C, the mutant and wild-type cells were not elongated and gave the same colony morphology. No changes in any other properties were found.
ICMSF methods studies. VI. The influence of selective enrichment media and incubation temperatures on the detection of Salmonella in dried foods and feeds
Authors: Gabis D. A. , Silliker J. H.
Published: April 2010

Recovery of Salmonella from low-moisture foods was studied using selective enrichment in tetrathionate brilliant green and selenite-cystine broths at 35C and 43C. A total of 1375 samples of dried dairy, soya, and rendered animal by-products were analyzed. All samples were preenriched before selective enrichment. No significant difference in recovery was detected between tetrathionate brilliant green and selenite cystine at either temperature, which is in contrast to our earlier findings with red meats. Pairing of enrichment conditions resulted in the detection of more positive samples than the use of any single enrichment condition.
Evidence that the nephrotoxin from the fungus Mortierella wolfii is a protein
Authors: Davey G. , Kalmakoff J.
Published: April 2010

A purified toxin from Mortierella wolfii contained about 60% lipid, 39% protein, and less than 0.4% carbohydrate. Labelling of the toxin, with the protein-alkylating agent 3H-iodoacetic acid and subsequent extraction of the lipid with a chloroform–ethanol–water mixture resulted in almost all of the radioactivity (97%) being present in the ethanol–water layer, suggesting that the lipid was not covalently linked to the protein. A threefold reduction in the lipid content of the toxin by ion-exchange chromatography did not reduce toxicity of the toxin, expressed in mean lethal dose (LD50) per unit of protein. The LD50 for mice is 3.3 μg protein. The cumulative findings suggested that the active toxic substance is a protein, with a high proline content (17.2% w/w) and a calculated molecular weight from amino acid analysis of 22 800 daltons.
Regulation of chloramphenicol synthesis in Streptomyces sp. 3022a. Properties of arylamine synthetase, an enzyme involved in antibiotic biosynthesis
Authors: Jones A. , Westlake D. W. S.
Published: April 2010

A new arylamine synthetase activity has been demonstrated in Streptomyces sp. 3022a when grown under chloramphenicol-producing conditions. The enzyme has several characteristics which distinguish it from anthranilate synthetase. It converts chorismic acid to an, as yet, unidentified aromatic amine easily separable from anthranilic and p-aminobenzoic acids. This arylamine synthetase was absent from strains of Streptomyces sp. 3022a, which were incapable of chloramphenicol production. The addition of chloramphenicol to growing cultures repressed arylamine synthetase but not anthranilate synthetase activity. The role of arylamine synthetase in the control and regulation of chloramphenicol biosynthesis is discussed.
Preservation of living fungi pathogenic for man and animals
Authors: Butterfield W. , Jong S. C. , Alexander M. T.
Published: April 2010

The paper describes the materials and procedures presently used at the American Type Culture Collection (ATCC) for the long-term preservation of living fungi pathogenic for man and animals by freeze-drying and by freezing and subsequent storage in liquid nitrogen. Longevity storage data for the strains available for distribution is presented.
In vitro measurement of cytotoxic antibodies in mouse-immune sera against mouse ascites tumor cells
Authors: Eng C. P. , Tolbert W. R. , Harnaha J. B. , Concannon J. P.
Published: April 2010

Previous studies reported that nontumorigenic 6C3HED tissue-culture cells induced strong tumor-specific immunoprotection against 6C3HED tumors. However, in the in vitro test, sera from C3H mice immunized with nontumorigenic 6C3HED tissue-culture cells failed to lyse 6C3HED ascites tumor cells when fresh guinea pig serum was incorporated as the complement source. A number of serum samples from different animal species were assayed as a complement source. With the exception of fresh rabbit serum, all other sera were either by themselves toxic to 6C3HED ascites tumor cells, or did not function as a complement source. The rabbit serum, by itself, was not toxic to 6C3HED tumor cells, but when incorporated with the isogeneic mouse-immune serum, killed more than 95% tumor cells. The facilitating activity exhibited by rabbit serum was characterized as classical complement and was not due to the presence of heterophile antibodies in the rabbit serum. By using this immunolytic testing system, the sera from mice bearing 6C3HED, S-180, TA-3, and Ehrlich solid tumors for an extensive time were found toxic to homologous ascites tumor cells. The cross-reactivity of the sera from tumor-bearing animals suggests that these four murine tumors, 6C3HED, S-180, TA-3, and Ehrlich, share some common tumor-specific antigen(s).
Biosynthesis of branched long-chain fatty acids by species of Bacillus: relative activity of three α-keto acid substrates and factors affecting chain length
Authors: Naik Devaray N. , Kaneda Toshi
Published: April 2010

An investigation of the fatty acid synthesizing systems of Bacillus cereus and Bacillus subtilis has been carried out to determine the factors which govern the comparative activity of branched short-chain α-keto acids as chain initiators, and the factors which determine the ensuing chain length.The B. cereus system requires the same components for fatty acid synthesis as established for B. subtilis: an α-keto acid substrate, malonyl CoA, NADPH, dithiothreitol, a heat-stable factor (HSF), and a protein fraction (enzyme). HSF and enzyme fractions from the two organisms are interchangeable. The comparative activity of the various α-keto acids depends upon a combination of these two components, the malonyl CoA concentration, and incubation temperature. In all cases, the HSF and enzyme from B. subtilis dominate over similar components from B. cereus. The activity of HSF from Escherichia coli was also studied.
Relationship between growth and metabolic activity in the strict chemolithotroph, Thiobacillus thiooxidans
Authors: Amemiya K.
Published: April 2010

The metabolic activity of Thiobacillus thiooxidans was found to decrease rapidly as stationary phase was approached. Keeping the culture at constant pH (4.0) and supplementation with CO2 did not effect the decrease in metabolic activity although growth was increased. The respiration rate of cells obtained from stationary phase was negligible. No growth was obtained when the pH was adjusted to pH 6.0. Measurement of pyruvic acid, an inhibitor of metabolic activity, showed that it reached only about 1.0 × 10−5 M during the early stages of growth and then decreased during exponential growth.
Effect of propagule size on the in vitro production of polygalacturonase and cellulase by Rhizoctonia solani
Authors: Lisker N. , Katan J. , Henis Y.
Published: April 2010

The physiological behavior of large (250–500 microns (μ)) infective and small (50–150 μ) non-infective mycelial fragments (propagules) of Rhizoctonia solani was compared. Liquid Czapek's medium containing sodium polypectate (NaPP) as the sole carbon source was inoculated with equal amounts (on a dry weight basis) of each kind of propagule. At NaPP concentrations of 0.005%–0.25% large propagules produced more polygalacturonase (PG) after a shorter period of incubation than small ones, whereas no differences in PG activity were observed at 1% NaPP. Differences in PG activity between large and small propagules were also observed in a medium consisting of 1:50 dilution of potato extract, but not in richer media such as potato dextrose broth and bean hypocotyl medium. These differences did not depend on pH of the medium or dry weight of the mycelium. Germination percentage of the large propagules and length of their emerging hyphae were greater than those of the small ones in media containing 0.005%–0.25% NaPP. Extracellular cellulase activity in Czapek's medium containing 0.25% carboxymethyl cellulose was also higher and appeared earlier in large propagules as compared with small ones. Viscometric and colorimetric methods for detecting PG and cellulase activities produced similar results. It is suggested that the capacity of the large propagules to produce hydrolytic enzymes at low nutrient levels may be important for their parasitic activity.
The reliability of selective media for the enumeration of unheated and heated staphylococci
Authors: Stiles M. E. , Clark P. C.
Published: April 2010

The relative efficiency of 15 selective media for enumerating unheated and sublethally heated strains of Staphylococcus aureus was tested against tryptic soy agar (Difco). Baird-Parker's egg yolk tellurite glycine pyruvate agar was found to be the medium of choice for both unheated and sublethally heated cells. Tellurite polymyxin egg yolk agar and egg yolk azide agar also gave favorable results. For unheated cells, Vogel-Johnson agar and tellurite glycine agar gave satisfactory results, but after heat treatment, even after a 10-h enrichment in tryptic soy broth for resuscitation of the heat injury, these media gave unreliable counts. Egg yolk acted not only as a diagnostic, but also as a protective agent in selective media for staphylococci. The protective action of egg yolk was more effective in azide- and tellurite-containing selective media than in salt-containing selective media.
Environmental factors affecting the degradation of Dyfonate by soil fungi
Authors: Flashinski S. J. , Lichtenstein E. P.
Published: April 2010

The ability of selected fungi to degrade the soil insecticide Dyfonate (O-ethyl S-phenyl ethylphosphonodithioate) into water-soluble, noninsecticidal metabolites was found to be dependent on the supply of nutrients, incubation time, temperature, pH, as well as other factors. With yeast extract as the carbon source (5 g/liter) and ammonium nitrate (1 g/liter) as the nitrogen source, both Rhizopus arrhizus and Penicillium notatum degraded the insecticide to a larger extent than with any other combination of nutrients used. With glucose as the carbon source, concentrations of ammonium nitrate above 5 g/liter inhibited the degradation of Dyfonate by R. arrhizus. Time-course studies on the metabolism of the insecticide indicated that Dyfonate was first absorbed by the fungal mycelium, where it was metabolized followed by the release of water-soluble, noninsecticidal, breakdown products into the culture media. The degradation appeared to involve the breakdown of Dyfonate into ethyl acetate soluble metabolites, such as ethylethoxyphosphonothioic acid, ethylethoxyphosphonic acid, methyl phenyl sulfoxide, and methyl phenyl sulfone. These compounds were then further degraded into water-soluble products. The optimum conditions for the degradation of the insecticide by R. arrhizus were observed at pH 6.0 to 7.0 and at 15–25 °C. Aged fungal mycelia were as active as mycelia in the logarithmic growth phase.
The effect of growth environment on the chloroform–methanol and alkali-extractable cell wall and cytoplasm lipid levels of Mucor rouxii
Authors: Safe S. , Caldwell J.
Published: April 2010

The distribution of chloroform–methanol and alkali-extractable lipids in the cell walls of aerobically grown filamentous cells from Mucor rouxii has been determined. The results have been compared with the corresponding lipid composition of yeast-like cells from M. rouxii, which can be produced in two ways: by growth under anaerobic conditions and by aerobic growth in the presence of 0.22% phenethyl alcohol (PEA). It was observed that in most cases the crude cytoplasmic fraction contained higher levels of several lipids (i.e., squalene, sterols, triterpenes, and fatty acids) than did the corresponding cell walls. The cell walls did, however, contain both "free" (chloroform–methanol extractable) and "bound" (alkali extractable) lipids although the relative amounts were markedly dependent on the cell growth environment. The aerobically grown filamentous cell walls contained higher levels of squalene, sterols, triterpenes, and fatty acids than did aerobically grown yeast-like PEA-induced cell walls and there was also considerable variation in the "free''/"bound" ratios of the various lipid components. The lipid levels in both the cell walls and cytoplasm of the anaerobically grown cells were considerably lower than those of the cells grown under aerobic conditions. In addition, the differences in the growth environment were also reflected in the compositions of the individual lipid fractions from both the cell wall and the cytoplasm fraction.
Immunochemical studies on burro antibodies to Histoplasma capsulatum
Authors: Sweet George H. , Tanner Carol G. , Wilson Donna E.
Published: April 2010

Burro antiserum to Histoplasma capsulatum was studied from the viewpoint of precipitating antibody distribution among euglobulins, pseudoglobulins, and immunoglobulin classes. By immunodiffusion analysis it was determined that throughout immunization most of the antibody was euglobular, but there was an increase in pseudoglobular antibody as immunization progressed. By immunoelectrophoretic and immunodiffusion analyses of specifically purified antibody, and antibody non-specifically fractionated by column chromatography and ultracentrifugation, it was established that there was no demonstrable IgM antibody, that most of the antibody appeared to be IgG, and that a γ1 immunoglobulin, probably IgA or T-globulin, may have been responsible for some of the activity. No major changes in the distribution of antibody among immunoglobulin classes seemed to occur during immunization.
Immunophyletic relationships between Actinomycetales and Eubacteriales determined by examinations of their cytoplasmic antigens
Authors: Kwapinski J. B. G. , Kwapinski E. H.
Published: April 2010

Cytoplasms obtained from a total of 205 different strains of Actinomycetales, Eubacteriales, Lower Fungi, and Protozoa were examined against selected anti-cytoplasm antisera using the immunodiffusion and counterimmunoelectrophoresis procedures. Immunological relationships between the different genera have been revealed and, in respect to Eubacteriales, the possible immunophyletic determinants have been discerned. Cytoplasms of Enterobacter, Clostridium, Staphylococcus, and Diplococcus were found to retain the significant linkage determinants between large groups of Eubacteriales and Actinomycetales.Evolutionary implications of the findings are discussed.
Basic characterization of a lipid-containing bacteriophage specific for plasmids of the P, N, and W compatibility groups
Authors: Bradley David E. , Rutherford Elizabeth L.
Published: April 2010

Preliminary studies have shown that bacteriophages PR3 and PR4, originally isolated on Pseudomonas aeruginosa, resemble the lipid-containing phage PM2 in appearance. Their host range extends intergenerically to species carrying drug-resistance plasmids of the P and N compatibility groups. In this paper, the serological identity of the two isolates is established and it is concluded that they are the same virus, but with some differences in growth characteristics. They contain double-stranded DNA and are probably icosahedra (65 nm) with short (47 nm) noncontractile tails. Their sensitivity to chloroform and low buoyant density in CsCl (1.265 g/ml) indicate that they contain lipid which is probably located in the thickened inner layer of the capsid. A study is made of their adsorption efficiencies to sensitive and resistant bacteria, and it is found that, unlike most sex-specific phages, they adsorb directly to the cell surface and not to sex pili. Their host range is shown to include strains harboring a drug-resistance plasmid of the W compatibility group.
Ultrastructural effects of lysozymes on the cell wall of Caryophanon latum
Authors: Trentini W. C. , Murray R. G. E.
Published: April 2010

When Caryophanon latum was exposed to egg white lysozyme in isotonic sucrose and observed by phase-contrast microscopy, protoplasts emerged along the length of the trichomes, apparently at sites corresponding to cross septa. Electron microscopy of sections revealed that this enzyme initially attacked the core of the septal peptidoglycan and delamination of septa resulted. The inner densely staining layer of the lateral and polar wall (considered to contain peptidoglycan as the major component) remained intact except for destruction at the advancing tip of partial septa; protoplasts or cell debris could escape from the gaps formed at developing septa. Treatment of intact trichomes with pronase, a lipase – phospholipase C mixture, EDTA, glutaraldehyde, or heat, before exposure to egg white lysozyme did not alter this pattern nor did it render the remaining peptidoglycan more susceptible to attack. The wall material external to the peptidoglycan was solubilized by pronase. The peptidoglycan remaining after lysozyme treatment was not morphologically changed by treatment with pronase. Lysozyme derived from Chalaropsis hydrolyzed incomplete septa initially, while the lateral and polar wall and complete septa were degraded later. Therefore, it is most probable that the inner dense layer does contain the peptidoglycan component and that some biochemical maturation distinguishes the substrate for these enzymes in the lateral wall and septa.
Photomicrography of nalidixic acid treated Hyphomicrobium neptunium: inhibition of bud formation and bud separation
Authors: Blackman Marcia A. , Weiner Ronald M.
Published: April 2010

Hyphomicrobium neptunium proceeds through a number of morphological stages during the course of its life cycle, but apparently only the bud formation and the bud separation stages are inhibited by nalidixic acid.
Occurrence of lactose-negative mutants in chemostat cultures of lactic streptococci
Authors: McDonald I. J.
Published: April 2010

Batch and chemostat cultures of Streptococcus cremoris HP and Streptococcus lactis 829 were examined for lactose-negative (lac−) mutants on indicator agar. In batch cultures, S. cremoris HP gave less than 1% of the total count as lac− colonies while S. lactis 829 consistently contained about 15% of the total as lac− colonies. In chemostat cultures of S. cremoris HP in 2% skim milk containing casamino acids and yeast extract (0.1% each), the percentage of lac− colonies increased markedly when the temperature of growth was 18 °C but not when the temperature of growth was 25 °C. The percentage of lac− colonies in chemostat cultures in the skim milk medium at 25 °C was about the same as that in batch cultures. On the other hand, when chemostat cultures of S. lactis 829 in the skim milk medium were grown at several temperatures between 18 and 33 °C, the percentage of lac− colonies was markedly lower than that found in batch cultures of this organism. Cultivation of S. cremoris HP in chemostats with yeast extract – lactose broth at low temperatures (14–18 °C resulted in cultures that gave plate counts on lactose agar, which were as much as 50% lower than counts on glucose agar but did not result in the selection of lac− mutants. Cultivation of S. lactis 829 in chemostats with yeast extract – glucose broth at low temperature (18 °C resulted in a selection of cells giving lac− colonies and atypical (small) lac+ colonies. The results show that cultivation of S. cremoris HP and S. lactis 829 in chemostats sometimes gave rise to altered populations. Conditions causing a change in one organism did not necessarily cause a similar change in the other. The results indicate that the successful propagation of lactic streptococci in chemostats for use as starter cultures in the dairy industry will require the careful establishment of optimum conditions for every strain so as to minimize the possible selection of undesirable populations.
Simplified procedures for releasing and concentrating microorganisms from soil for transmission electron microscopy viewing as thin-sectioned and frozen-etched preparations
Authors: Balkwill D. L. , Labeda D. P. , Casida Jr. L. E.
Published: April 2010

A simplified procedure is presented for releasing and concentrating indigenous microbial cells from soil for viewing by transmission electron microscopy as thin sections or replicas of frozen-etched preparations. This procedure is compared with two others reported earlier, and their relative merits are discussed as concerns the choice of procedure for the cellular information desired from the soil. Freeze-etching showed that the cell types and size distributions for cells which have been released and concentrated from soil are in general agreement with those for cells in a crude soil slurry in which no attempt to release and concentrate cells was made. Microcolonies were present both in the crude slurry and in the discard soil debris centrifugation pellets from the cell release and concentration procedures. In contrast to the historic assumptions, these microcolonies, as well as some individual cells embedded in soil debris could not be broken up and (or) dislodged so that they would be washed from the soil. The relative numbers of these cells remaining with the soil debris, however, could not be quantitated in the present study.
Glycolytic enzymes in resting spores and vegetative mycelia of Entomophthora pyriformis
Authors: Tyrrell David , Simpson Janet E.
Published: April 2010

Specific activities of 14 enzymes of the Embden–Meyerhof–Parnas and pentose phosphate pathways were determined in extracts of resting spores and vegetative mycelia of Entomophthora pyriformis. All these enzymes were detected in mycelial extracts, whereas only nine were detectable in resting spore extracts. Activities of detectable spore enzymes were much lower than those of the corresponding mycelial enzymes with the exception of triosephosphate dehydrogenase, which had higher activity in spore extracts. The enzyme deficiencies noted point to the inability of either pathway to function in dormant spores.
Lysosomes and the "toxicity" of Rickettsias. VI. In vivo response of mouse peritoneal phagocytes to L-cell-grown Chlamydia psittaci 6BC strain
Authors: Kordová Nonna , Wilt John C. , Martin Caroline
Published: April 2010

The L-cell-grown 6BC strain of C. psittaci inoculated intraperitoneally in mice induced an injurious effect on mononuclear phagocytes and their lysosomes; the influx of polymorphonuclear phagocytes (PMN's) increased markedly and the PMN's showed karyorrhexis and lysis. Cytochemical methods failed to detect chlamydial forms in peritoneal fluids from day 1 and up to 6 days after inoculation of mice. Chlamydial infectivity was not detected in either the cell-bound or the cell-free fractions of peritoneal cells from 6 h up to 6 days after inoculation of mice. In contrast, after infection of mice with the egg-grown 6BC strain, readily identifiable multiplication of the parasites occurred from 4 days after inoculation of mice; the lysosomes of macrophages were refractory to egg-grown 6BC particles that were initially ingested and the macrophages were nonspecifically "activated." Some of these "transformed" into large epitheloid cells containing numerous chlamydial inclusions in the cytoplasm. That lysosomes of "professional phagocytes" play a role in the "toxic" effect of virulent chlamydiae in the intact host is discussed.
Preliminary observations on the protective action of a cytoplasmic immunogen of Neisseria gonorrhoeae
Authors: Kwapinski J. B. G. , Cheng A.
Published: April 2010

A non-toxic protein, termed β(−t), consisting of lysine, aspartic acid, threonine, serine, glutamic acid, glycine, and alanine (1.2:1.3:1.3:3:2.2:7:1) was isolated, by the polyacrylamide gel electrophoresis, from an isoelectric toxic proteinaceous fraction β(+t) of the type 1 cytoplasm of N. gonorrhoeae. The β(−t) antigen elicited delayed hypersensitivity and vigorous primary and secondary humoral responses in rabbits, and it conferred immune protection against intraocular gonococcal infections.
Optimum conditions for initiation of filamentation in Candida albicans
Authors: Evans E. G. V. , Odds F. C. , Richardson M. D. , Holland K. T.
Published: April 2010

A medium that initially produced filaments from almost all of its Candida albicans blastospore inoculum contained 1% mycological peptone and 0.2% glucose, final pH 7.4–7.5. The medium was inoculated to 106 cells/ml and incubated at 40 °C. Reversion to secondary blastospores began at a mean of 2.4 h after inoculation. The patterns of utilization of growth nutrients during optimal mycelial growth showed no correlation with the events of filamentation.
Reversal of fungitoxicity of 8-quinolinols and their copper (II) bischelates. I. Amino acids and related compounds
Authors: Gershon Herman , Parmegiani Raulo , Hauck Janice Baricko
Published: April 2010

The effect of amino acids and related compounds on the toxicity of 8-quinolinols and their copper(II) bischelates to Aspergillus oryzae (ATCC 1011) was studied. None of the compounds tested except the thiol-containing compounds cysteine, cysteamine, glutathione, and N-acetylcysteine reversed the inhibitory action of 8-quinolinol but not that of 5-iodo-8-quinolinol or bis(8-quinolinolato)copper(II). It appears that the mechanism(s) of fungitoxicity of 8-quinolinol is different from that of 5-iodo-8-quinolinol or bis(8-quinolinolato)copper(II).
Serological relationship between Gloeophyllum trabeum and Gloeophyllum saepiarium
Authors: Madhosingh Clarence , Ginns James
Published: April 2010

Gloeophyllum trabeum (Fr.) Murr. produced eight precipitin lines in homologous serological reactions in double-diffusion experiments. Five of these lines were similar to the precipitin lines developed with G. saepiarium (Fr.) Karst. antigens, indicating a close serological relationship between the two organisms.
The non-light-dependent reduction of 2,6-dichlorophenolindophenol by cells of the blue-green alga Anacystis nidulans
Authors: Ward Bailey
Published: April 2010

Whole cells of the blue-green alga Anacystis nidulans reduced, in the dark, the oxidation–reduction dye, 2,6-dichlorophenolindophenol at rates severalfold higher than those of the other algae tested. Under anaerobiosis, the endogenous reductant was depleted after up to 80 nmol of dye were reduced per microliter of cells. Cells held in darkness for several hours exhibited lowered dark reduction rates relative to cells held in light. Treatment with lysozyme and ethylenediaminetetraacetic acid yielded cells that would photoreduce the dye, whereas untreated cells would not. Comparisons of photoreduction and dark reduction revealed that the dark reduction proceeded independently of the photoreduction. It was concluded that the dark reduction represents a pool of endogenous reductant of sufficiently low oxidation–reduction potential to reduce completely 2,6-dichlorophenolindophenol. Additionally, untreated cells were shown to be permeable to the dye although they did not photoreduce it; thus lysozyme/ethylenediaminetetraacetic acid treatment was considered to make the oxidant accessible to the photosynthetic machinery.
California encephalitis virus development in mosquitoes as revealed by transmission studies, immunoperoxidase staining, and electron microscopy
Authors: McLean D. M. , Gubash S. M. , Grass P. N. , Miller M. A. , Petric M. , Walters T. E.
Published: April 2010

Isolates of the snowshoe hare subtype of California encephalitis (CE) virus from Yukon mosquitoes during 1972 and 1973 were transmitted by bites of Aedes aegypti mosquitoes after 4 to 5 weeks of extrinsic incubation at 55°F after intrathoracic injection, and the 1973 strain was transmitted after mosquitoes were fed virus and held for 3 to 4 weeks at 75°F. Antigen of a 1971 isolate of CE virus (Marsh Lake 23) was detected in salivary glands of infected mosquitoes by the immunoperoxidase technique, using highly purified antiserum before and after conjugation with horseradish peroxidase, plus the use of orthotolidine as a substitute for benzidine. Enveloped virions 45 nm in diameter were observed in thin sections of salivary glands of Culiseta inornata mosquitoes 59 days after intrathoracic injection with the 1971 isolate, after incubation at 55°F.
Fungal fimbriae. III. The effect on flocculation in Saccharomyces
Authors: Day A. W. , Poon N. H. , Stewart G. G.
Published: April 2010

Flocculent strains of Saccharomyces cerevisiae and S. carlsbergensis (S. uvarum) produced many short (0.5 μm) hairs (fimbriae) on the outer cell walls. Non-flocculent strains produce few fimbriae. Cells that are flocculent in wort but not in defined medium produce fimbriae only in the former medium. Cells treated with pronase lose both their fimbriae and the ability to flocculate. Cells treated with α-amylase retain some fimbriae but lose the ability to flocculate. It is suggested that the fimbriae may be the surface mannan–protein complexes known to be involved in flocculation and also in protein secretion. Haploid cells of both mating types also produced fimbriae, some of which apparently have a terminal knob.
Degradation of feather keratin by culture filtrates of Streptomyces fradiae
Authors: Young R. A. , Smith R. E.
Published: April 2010

Treatment of milled defatted capon feathers with filtrates of Streptomyces fradiae ATCC 10745 that had been concentrated 20 times showed that the most keratin degradation in 0.5 h occurred at pH 8.0 and 60 °C. If assay time was extended, however, a decrease in reaction rate occurred and appeared to result from keratinase instability at elevated temperatures. Exposure of commercial feather meal to unconcentrated culture filtrates for 15 h produced greatest degradation at 50 °C.
Production of methionine-excreting mutants of Streptomyces fradiae
Authors: Young R. A. , Smith R. E.
Published: April 2010

Methionine-excreting mutant strains of Streptomyces fradiae ATCC 10745, produced by exposure to N-methyl-N′-nitro-N-nitrosoguanidine, were selected on the basis of ethionine-resistance and ability to support the growth of an auxotroph which required methionine or methionine precursors. When acid hydrolysates of dehydrated liquid cultures were analyzed for amino acid content, one of the mutants had produced 268% more methionine than the parental strain. To obtain an accurate analysis of methionine content, it was necessary to determine the amount of diaminopimelic acid which had been synthesized. This compound appeared in eluates during column chromatography at about the same time as methionine, and its presence increased apparent methionine concentrations by 25 to 40%.
Effect of lactobacilli and carbon dioxide on the growth of Microbacterium thermosphactum on fresh beef
Authors: Roth L. A. , Clark D. S.
Published: April 2010

Studies with artificially inoculated fresh beef showed that lactobacilli markedly restrict the growth of Microbacterium thermosphactum when the beef is vacuum-packaged. High concentrations of carbon dioxide (up to 75%) had little effect on the growth of M. thermosphactum under either aerobic or anaerobic conditions. Tests were made with samples of lean beef inoculated with pure cultures of lactobacilli and (or) M. thermosphactum and stored unpackaged in air, in air enriched with carbon dioxide, in nitrogen – carbon dioxide mixtures, or vacuum-packaged as in commercial practice. On vacuum-packaged meat, growth of M. thermosphactum was extensive in the absence of lactobacilli, but was restricted in the presence of lactobacilli. On unpackaged meat (i.e. stored in air) this inhibition did not occur, showing that anaerobic conditions are necessary for it to take place. These results show the importance of lactobacilli on the storage life of vacuum-packaged fresh beef.
Antibody production in goat milk serum after virus instillation of goat mammary gland. VII. Biochemical studies on sham infection with rabies and other non-propagating agents
Authors: Pasieka Arthur E. , Guerin L. F. , Mitchell Chas. A.
Published: April 2010

This report describes the development of a method for the production and isolation of neutralizing antibodies against rabies virus (ERA strain) and other agents in the goat mammary gland during active lactation. The rabies virus did not propagate in the gland, but neutralizing antibodies were produced by serial instillations of the antigen. This process was termed 'sham infection.' Antibodies first appeared in the milk about the 20th day and the titer increased until the 28th day. The antibodies were found to be associated with the lactogammaglobulin. The milk globulins were fractionated by gel chromatography and the fraction containing the antibody was isolated. This fraction was further purified and characterized by immunodiffusion, immunoelectrophoresis, and an analytical ultracentrifugation technique. The neutralizing antibody activity after the 29th day was associated with the milk serum IgG fraction. This active fraction was found to have a sedimentation coefficient of 6.8 Svedberg units.
Host response to infection by Coxiella burneti
Authors: McDonald Thomas L. , Mallavia L. P.
Published: April 2010

A host response to infection by Coxiella burneti was investigated. Infected yolk sacs were harvested from embryonated eggs and assayed for glycolytic activity. Assays of glycolytic enzymes included glucose isomerase, aldolase, phosphofructokinase, fructose-1,6-diphosphatase, glyceraldehyde-3-phosphate dehydrogenase, enolase, and pyruvate kinase. No significant differences in enzymatic activity between normal and infected tissues through the 12th day were observed. From the 13th day through the 16th day, the glycolytic activity of normal tissues decreased. Glycolytic activity of infected tissues did not decrease, but showed a gradual increase during this same time period. Embryos from infected eggs demonstrated a gradual decrease in total weight from the 12th day until death occurred on the 16th day.