bluuebunny/crossref_metadata_2025 huggingface dataset:
Polygalacturonic acid transeliminase production by Azospirillum species
Authors: Tien T. M. , Diem H. G. , Gaskins M. H. , Hubbell D. H.
Published: May 2010

Polygalacturonic acid transeliminase (PATE) was produced by all of six Azospirillum strains studied. Characteristics were similar to those of PATE from other bacteria: activity was maximal at pH 8.0 and was stimulated by CaCl2. Polygalacturonic acid was used more readily than pectin as a substrate. Polygalacturonic acid in the medium stimulated PATE production by several but not all strains. In all cases some of the PATE produced in cultures remained bound to cell walls. In one strain, most remained cell wall bound. When nitrogen was supplied as amino acids rather than ammonium salts, the ratio of free to bound enzyme was increased. The strains studied varied considerably in response to nutrient amendments and in maximum PATE activity.
K+, Na+, and Mg2+ content and permeability of Methanospirillum hungatei and Methanobacterium thermoautotrophicum
Authors: Sprott G. D. , Jarrell K. F.
Published: May 2010

The K+, Na+, and Mg2+ contents of Methanospirillum hungatei and of the thermophile Methanobacterium thermoautotrophicum were determined at various phases of growth. The intracellular K+ content of exponential phase cells of M. thermoautotrophicum (approximately 780 mM) was 5.4-fold higher than in M. hungatei, and decreased gradually as the culture entered the stationary phase. Both methanogens concentrated Mg2+, exhibiting an increased content as the cultures aged. Comparisons among extraction methods showed that most of the internal K+ was readily released, but a minimum of half of the Mg2+ in M. hungatei, and most of the Mg2+ in M. thermoautotrophicum, was in a bound form. Exponential phase cells of M. hungatei established an intracellular level of Na+ lower than the outside medium, but the thermophile concentrated Na+.Dextran, inulin, sucrose, and glucose penetrated cell pellets to varying degrees and could be used to measure the space corresponding to cytoplasm and to cell wall permeability barriers. L-Phenylalanine penetrated fully and acetate accumulated in both methanogens. Acetate uptake in cell suspensions of M. hungatei was fully inhibited by oxygen, N-ethylmaleimide, or N,N′-dicyclohexylcarbodiimide, but was not affected by the proton conductor carbonylcyanide p-trifluoromethoxyphenylhydrazone. L-Malate, which penetrated M. hungatei cells poorly, was metabolized to glutamate, indicating the presence of an incomplete reductive carboxylic acid cycle.
Motility and chemotaxis of three strains of Pseudomonas aeruginosa used for virulence studies
Authors: Craven Rebecca C. , Montie Thomas C.
Published: May 2010

The motility and chemotaxis of three strains of Pseudomonas aeruginosa were examined by electron microscopy, soft agar migration, and the capillary assay test. Strain M2, which is highly virulent in the burned mouse model, was vigorously motile and highly chemotactic. The avirulent strains tested, PA103 and WR5, were defective in motility and chemotaxis, respectively. These results suggest that considerable heterogeneity in chemotactic capacity exists among the P. aeruginosa strains that are used for virulence studies, and further, that chemotaxis should be examined as a possible virulence factor for P. aeruginosa.
Nitrogen fixation and methane metabolism in a stream sediment–water system amended with leaf material
Authors: Tam T.-Y. , Mayfield C. I. , Inniss W. E.
Published: May 2010

The reduction of acetylene and the production and oxidation of methane in a stream sediment–water system amended with either fresh leaves or autumn-shed leaves in the presence and absence of air were studied. Net methane production by the sediment–water system occurred only when leaf material was added, with fresh leaves giving 2.2 times the methane accumulation as autumn-shed leaves. Static incubation in the presence of air had little effect on net methane production, with such production being about the same as (with fresh leaves) or 79% of (with autumn-shed leaves) the anaerobic rates. Acetylene reduction was more affected by the presence of air, with anaerobic rates being at very low levels. The presence of fresh leaves was again stimulatory, with the acetylene reduction rate being 5.5-fold greater than that occurring with autumn-shed leaves.
Glutaraldehyde reactions with alkaline phosphatase of Pseudomonas aeruginosa
Authors: Day D. F. , Ingram Jordan M.
Published: May 2010

Glutaraldehyde, the biological fixative of choice in the cytochemical localization of the phosphatases, was investigated for its effects on Pseudomonas aeruginosa alkaline phosphatase. Comparative studies on the inactivation of alkaline phosphatase by glutaraldehyde showed significant differences when the purified protein was compared with whole, cell-bound enzyme.The effects of the reagent on the kinetics of the purified enzyme were studied and some conclusions drawn as to the mode of inactivation. The reaction of glutaraldehyde with the cell envelope of P. aeruginosa was also investigated, and it was found not to modify the extraction of lipopolysaccharides from the outer membrane. This study emphasizes the care that must be taken to interpret data, cytochemical or otherwise, obtained when glutaraldehyde is used as a fixative or cross-linking reagent.
Changes in the chemical composition of oospores of Pythium aphanidermatum during bimodal germination
Authors: Ruben D. M. , Frank Z. R. , Chet I. , Sklan D.
Published: May 2010

The developmental mode by which oospores of Pythium aphanidermatum germinate may be controlled by the concentration of glucose present in the germination medium. When incubated in a liquid medium containing emulsified lecithin without added glucose (S + L), oospores germinated indirectly, with zoospore release occurring during the 10th to 13th h. A decrease in dry weight of the fungus took place by the 13th h of indirect germination. When 0.2 mM glucose was added to S + L, the dry weigh of germlings increased and direct germination occurred without zoospore formation. Polar lipid comprised the bulk of total acylglycerides of dormant oospores. A greater decrease in total fatty acid content took place during direct germination that during indirect germination. During both developmental modes of germination, polar lipid content decreased considerably neutral lipids, however, increased during indirect germination and decreased during direct germination. Protein content of the fungus increased in both developmental modes of germination, being initally 9.7% of the dry weight of dormant oospores. After 13 h of incubation, KOH-soluble polysaccharide decreased by 35% during direct germination and by 48% during indirect germination.
Hemagglutination by Neisseria meningitidis
Authors: Salit Irving E.
Published: May 2010

The direct agglutination of erythrocytes by Neisseria meningitidis was studied as a marker for adherence. Hemagglutination (HA) was studied by slide test (5-min incubation) and by dilutions in microtitre plates (20-h incubation). Meningococci that were freshly isolated from subjects agglutinated only human cells by slide test but human, dog, rabbit, guinea pig, and rat cells were agglutinated in the microtitre system. Newly isolated strains were piliated and HA positive but pili were lost after 10 passages on agar, and bacteria became HA negative. HA could be maintained by "affinity culturing," which selected markedly adhesive bacteria: erythrocytes with adherent meningococci were isolated and cultured on agar. This procedure was repeated daily. HA titres were unaffected by mannose but were reduced by sonic disruption, trypsinization, ultraviolet irradiation, heating (65 °C), and formaldehyde. Encapsulated (serogroupable) bacteria had low HA titres compared with nongroupable strains, and purified capsular polysaccharides A and C inhibited HA. Meningococcal HA is probably mediated by pili and modified by other factors such as encapsulation. Colonial variation was not a reliable indicator of piliation, and HA is best used for this purpose.
The assay of adenosine 5′-triphosphate extracted from salt-marsh microbiota
Authors: Stevenson L. Harold , Wilson Charles A. , Chrzanowski Thomas H.
Published: May 2010

The light-emitting reaction of firefly luciferin and luciferase is a common ingredient in the quantification of adenosine triphosphate (ATP) extracted from the microbiota of environmental samples. Both portions of the light-emission phase of the luciferase reaction, the primary flash within 3 s of mixing and the secondary decay in the luminescence following the flash, have been used to quantify extracted ATP. However, the magnitude of the secondary phase is influenced by nucleotides other than ATP. The impact of this influence on the quantification of ATP was studied in samples collected from the water covering a salt marsh. Analysis by integration of the secondary decay portion of the emission yielded values of ATP per cubic metre that were consistently higher than those obtained by peak height analysis of the same extracts. Assays using the integration technology resulted in values that were up to 8 [Formula: see text] times higher than corresponding values determined by peak height analysis in unfractionated samples (total microbial biomass) and up to 16 [Formula: see text] times higher in water that had been prefiltered with a 1.0 μm filter (bacterial biomass).
Streptomyces setonii: catabolism of vanillic acid via guaiacol and catechol
Authors: Pometto III Anthony L. , Sutherland John B. , Crawford Don L.
Published: May 2010

Streptomyces setonii (strain 75Vi2) was grown at 45 °C in liquid media containing simple aromatic compounds as principal carbon sources. Thin-layer chromatography, UV spectrophotometry, and gas chromatography were used to show that S. setonii converted benzoic acid, guaiacol, and vanillic acid to catechol; p-hydroxybenzoic acid to protocatechuic acid; and m-hydroxybenzoic acid to gentisic acid. Presence of the ring-cleavage enzymes catechol 1,2-dioxygenase, protocatechuate 3,4-dioxygenase, and gentisate 1,2-dioxygenase was shown both by O2 uptake in ring-cleavage reactions catalyzed by cell-free extracts and by changes in UV spectra that indicated the presence of specific ring-cleavage products. A unique feature of this strain was its catabolism of vanillic acid by way of guaiacol and catechol, using a pathway that had not been confirmed previously.
Hanseniaspora nodinigri, a new yeast species found in black knots (Dibotryon morbosum) of Prunus virginiana
Authors: Lachance Marc-André
Published: May 2010

The new yeast species Hanseniaspora nodinigri is described to accommodate members of the genus Hanseniaspora that are unable to assimilate glucono-δ-lactone and isolated from stromatal tissue of black knots (Dibotryon morbosum) of chokecherry, Prunus viriginiana. The newly described taxon shows much resemblance, by other criteria, to H. vineae van der Walt et Tscheuschner and H. osmophila (Niehaus) Phaff, Miller et Shifrine.
Germination of macroconidia and growth of Sporidesmium sclerotivorum in vitro
Authors: Ayers W. A. , Barnett E. A. , Adams P. B.
Published: May 2010

Macroconidia of Sporidesmium sclerotivorum, a mycoparasite of Sclerotinia spp., were induced to germinte by aqueous and ethanolic extracts of sclerotia of Sclerotinia minor. Paper chromatography of sclerotial extracts indicated the presence of several amino acids and carbohydrates, chiefly glucose. Glucose was identified as the principal germination stimulant in ethanolic extracts. Glucose, fructose, mannose, cellobiose, sucrose, maltose, trehalose, soluble starch, and glycerol at 0.1% (w/v) stimulated macroconidia to germinate in 3–6 days at 25 °C. Crude sclerotial extracts, and glucose combined with inorganic and organic nitrogen sources, supported germination of greater numbers of macroconidia than glucose alone. Yeast extract, Casaminc acids, peptone, and several carbon substrates alone did not support germination. Macroconidia germinated well (> 30%) over the range of pH 3–7; maximum germination (> 80%) occurred at pH 5.0–5.5. Mycelial growth in a glucose – Casamino acids - mineral salts medium was also greatest in the range of pH 5.0–5.5, but growth fell off sharply below pH 4.5 and above pH 6.0. The fungus grew slowly on several complex agar media adjusted to pH 5.5.
Lipid level and total fatty acid composition for selected developmental stages of Entomophthora egressa
Authors: Dunphy Gary B. , Keough K. M. W. , Nolan Richard A.
Published: May 2010

The major fatty acids (> 10%) of Entomophthora egressa were C16:0 and C18:1. Minor fatty acids, which varied with the stage of fungal development, included C11:0, C12:0, C13:0, C14:0, C15:0, C16:1, C17:0, C18:0, C18:2, C18:3, C20:1, C20:2, C20:3, C20:4, C20:5, and two unidentified unsaturated fatty acids. Differences were observed between the total fatty acid levels of C12:0, C14:0, C17:0, C18:0, and C20:5 and the degree of unsaturation of the fatty acids of 37-h protoplasts grown in modified Grace's medium and a simplified growth medium (SGM). The levels of C12:0, C14:0, C18:1, C20:4, and C20:5 decreased and the levels of C18:0 and C20:2 increased with the formation of spherical hyphal body (shb) initials. With the production of mature shb increased levels of C12:0, C14:0, C15:0, C18:1, C20:4, and C20:5 were detected. During the germination of the shb the levels of C14:0, C16:1, C18:1, and C20:4 increased, whereas C15:0 and C20:5 levels declined. The fatty acid levels, except for Cl2:0, C13:0, and C20:2, remained constant during the mycelial stage. The degree of fatty acid unsaturation decreased during early stages of development (protoplasts through shb initials). In SGM the degree of fatty acid unsaturation was lowest during the shb initial stage and highest during the shb stage. The total lipid level increased during shb maturation and declined during shb germination.
The effect of polarization on the attachment of marine bacteria to copper and platinum surfaces
Authors: Gordon Andrew S. , Gerchakov Sol M. , Udey Lanny R.
Published: May 2010

Electrochemical polarization of copper and platinum was shown to affect the attachment of two marine bacteria to the surfaces of these metals in seawater. Attachment of both bacteria to copper surfaces was enhanced by polarizing the metal cathodically, whereas attachment was reduced when the copper was anodically polarized. Anodic polarization of platinum also retarded bacterial attachment but overpotentials higher than those for copper were required to produce the same effect. The pH was measured at a distance of 50 μm from the polarized surfaces. Changes in pH at the metal–seawater interface correlated with the attachment of bacteria, and may have influenced bacterial attachment to polarized surfaces.
Modification du bacille de Koch par un matériel extrait de lésions de tuberculose
Authors: Lafont Jeanne , Lafont Philippe
Published: May 2010

Lymph node lesions of tuberculous cattle and swine gave, after disruption, centrifugation through 2.2 M sucrose, and ultrafiltration, a material that brings about, in vitro, modification of the tubercle bacilli or chromogenic mycobacteria into bacterial elements that are not acid fast, rapidly growing on nutritive agar supplemented with glycerol. The phenomenon is similar to that which the authors have previously described, using an inducing agent extracted from cultures of mycobacteria, called "endometallaxic conversion."
The microbiology of spent mushroom compost and its dust
Authors: Kleyn John G. , Wetzler Theodore F.
Published: May 2010

Microorganisms in spent steamed mushroom compost and its dust were enumerated, isolated, and identified. Some phase II (indoor composting) compost samples were also examined. Steaming of spent compost resulted in a 70–76% reduction in microbial numbers. Total counts made with compost infusion agar were approximately two logs greater than those for nutrient agar.The most common bacterial isolate was Bacillus licheniformis. The most common actinomycete isolates were Streptomyces diastaticus and Thermoactinomyces vulgaris. Other actinomycete isolates included Streptomyces albus, Streptomyces griseus, Thermoactinomyces thalpophilis, Thermomonospora chromogena, and Thermomonospora fusca.The most common fungal isolates were Aspergillus fumigatus and Humicola grisea var. thermoidea. Other fungal isolates included Aspergillus flavus, Aspergillus nidulans, Aspergillus terreus, Aspergillus versicolor group, Chrysosporium luteum, Mucor spp., Nigrospora spp., Oidiodendron spp., Paecilomyces spp., Penicillium chrysogenum, Penicillum expansum, Trichoderma viride, and Trichurus spp.
Effect of chemical and pharmacological agents on the secretory activity induced by Escherichia coli heat-stable enterotoxin
Authors: Knoop Floyd C. , Abbey David M.
Published: May 2010

The effect of aspirin (ASP), chlorpromazine (CPZ), diphenoxylate (DP), ethylene glycol tetraacetate (EGTA), hydrocortisone (HC), loperamide (LPA), methylprednisolone (MP), phenotolamine mesylate (PTM), propranolol (PR), and trifluoperazine (TPZ) on the secretory activity induced by Escherichia coli heat-stable (ST) enterotoxin in infant mice was studied. LPA and DP, which are used therapeutically for diarrhea, did not inhibit the effect of ST enterotoxin; MP and HC, known inhibitors of cholera enterotoxin, and two adrenergic agents (PR and PTM) had no effect on ST-induced secretory activity. TPZ, EGTA, ASP, and CPZ caused a significant (P < 0.05) decrease in the secretory activity induced by ST enterotoxin. CPZ, EGTA, and TPZ inhibited secretory activity induced by 8-bromoguanosine 3′5′-cyclic monophosphoric acid (8-BrcGMP), a cGMP analog.
Transformation of Pseudomonas syringae with nonconjugative R plasmids
Authors: Gross Dennis C. , Vidaver Anne K.
Published: May 2010

Transformation of Pseudomonas syringae strains with plasmid DNA occurs at a frequency of 1 × 10−3 to 4 × 10−9 per recipient cell, depending on the strain, plasmid, and conditions for transformation. R plasmids used successfully in transformation were pR0161 (26 × 106 molecular weight) and RSF1010 (5.5 × 106 molecular weight). Transformation involved growing the recipient cells to approximately 8 × 108 colony-forming units per millilitre in 50 mL of a nutrient broth. After washes with a 150 mM CaCl2 – 10% (v/v) glycerol mixture, cells were concentrated 20-fold and resuspended in this solution. The cells then were incubated with purified plasmid DNA for 1 h prior to a heat pulse at 45 °C for 2 min. Transformants were selected by antibiotic resistance and plasmid presence was verified by agarose gel electrophoresis. With plasmid pCG131 (34 × 106 molecular weight; putatively associated with syringomycin production), transformation of syringomycin-negative P. syringae strains that contained no detectable plasmid or were cured of pCG131 was unsuccessful, whether the plasmid was used alone or in combination with either pR0161 or RSF1010.
Stable isotope fractionation by Clostridium pasteurianum. 4. Sulfur isotope fractionation during enzymatic S3O62−, S2O32−, and SO32− reductions
Authors: Harrison G. I. , Laishley E. J. , Krouse H. R.
Published: May 2010

Cell-free extracts from Clostridium pasteurianum grown on SO32− utilize H2 to reduce S3O62−, S2O32−, and SO32− to H2S at a much faster rate than extracts from SO42−-grown cells. This further supports the concept of an inducible dissimilatory type SO32− reductive pathway in this organism. 35S dilution experiments further support the concept that S3O62− and S2O32− are pathway intermediates. The inducible SO32− reductase is ferredoxin linked and the kinetics of the reduction and the sulfur isotope fractionation of the product can be altered by altering the growth conditions. The attending sulfur isotope fractionations are similar to those observed during the chemical decomposition of these compounds. In the case of S2O32−, 35S labelling experiments verified the conclusions derived from the stable isotope fractionation data concerning the relative reduction rates of the sulfane and sulfonate sulfurs. The reduction rates were also affected by enzyme concentration. The integrity of the whole cell is a necessary requirement for the large inverse isotope effects previously reported.
Changes in the activity of antifungals in mixed cultures of bacteria and yeasts
Authors: Domon M. H. , Mathieu L. G. , Repentigny J. de
Published: May 2010

When Candida cells were grown in mixed cultures with Escherichia coli, Salmonella typhimurium, or Pseudomonas aeruginosa, their sensitivity to antifungal agents affecting sterol metabolism or functioning (polyenes and miconazole) was increased by several log units. This phenomenon was overcome by the addition to the culture medium of sugars utilized either by the bacteria or the yeast. Antifungals without direct effect on sterol metabolism (5-fluorocytosine, methylparaben, and 4-hydroxyquinazoline) were not more active in mixed than in pure cultures.
Identification of sterigmatocystin as a metabolite of Monocillium nordinii
Authors: Ayer William A. , Pena-Rodriguez Luis , Vederas John C.
Published: May 2010

Sterigmatocystin, a potent hepatocarcinogen, has been identified as one of the metabolites of Monocillium nordinii (Bourchier) W. Gams.
A simple procedure for partial purification of an RNAase of Entamoeba invadens
Authors: Weller David L. , Richman Andrea
Published: May 2010

The behavior of an RNAase, present in centrifugally clarified homogenates of axenic trophozoites of Entamoeba invadens, on isoelectric focusing (IEF) and agarose–poly(G) chromatography is described. The results led to a simple two-step procedure for partial purification of the RNAase in which fractionation of the homogenate by IEF is followed by agarose–poly(G) chromatography. Recovery of enzyme activity has ranged from 50 to 80% of that present in homogenates, and increases of 80- to 160-fold in the specific activity have been obtained using the procedure. A single zone of activity was observed on analysis of the partially purified RNAase by sucrose gradient IEF and velocity zonal ultracentrifugation.
Effects of carbon and nitrogen supplementation on lignin and cellulose decomposition by a Streptomyces
Authors: Barder Maichael J. , Crawford Don L.
Published: May 2010

Effects of nitrogen source and concentration and organic carbon cosubstrates on lignin and cellulose degradation by Streptomyces badius strain 252 were examined using 14C-labeled substrates prepared from Pseudotsuga menziesii twigs. As compared with white-rot fungi, which do not degrade lignin in the absence of a readily metabolizable carbon cosubstrate, degradation of a milled-wood lignin occurred in a minimal medium, although degradation by S. badius was greatly enhanced when organic nitrogen and an organic carbon cosubstrate were added to the medium. Lignin degradation was greatest in the presence of high levels of organic nitrogen. Further enhancement of lignin and cellulose degradation occurred in a medium containing organic nitrogen supplemented with low levels of NO3−. The specific effects of inorganic nitrogen on lignocellulose degradation by S. badius in an otherwise optimal medium included both enhancement and inhibition of lignin or cellulose degradation depending on the source and concentration of inorganic nitrogen used. These effects were distinctly different from those observed with white-rot fungi and were shown to be specific ion effects on polymer degradation and not simply a salt concentration effect on cellular growth.
Bacillus thuringiensis distribution in soils of the United States
Authors: DeLucca II Anthony J. , Simonson Janet G. , Larson A. D.
Published: May 2010

During a 2-year study, samples of various types of soils were collected from 115 fields that had not previously been treated with Bacillus thuringiensis and which were remote from any large-scale aggregations of lepidopterous insects in rearing or grain-storage areas. An average of about 400 isolates were examined from each soil, and, of 46 373 isolates examined, only 250 (0.5%) were identified as B. thuringiensis. While it was almost impossible to insure that a field had never been treated with B. thuringiensis or that drift from some nearby application had not reached the field, it is noteworthy that of the 250 isolates, 156 (62.4%) were not var. kurstaki, the only variety that has been used commercially in the United States in about 10 years. This is a strong indication that the B. thuringiensis isolates observed were present naturally. To verify the procedures used, samples were taken from two adjacent experimental plots which had been treated about 12 months previously with formulations of var. kurstaki and var. galleriae, respectively. With practically no exception, the variety recovered from each plot was the variety applied, indicating that the varietal status of B. thuringiensis is stable in the soil.
Denitrification and dissimilatory nitrate reduction to ammonium in digested sludge
Authors: Kaspar Heinrich F. , Tiedje James M. , Firestone Richard B.
Published: May 2010

Acetylene inhibition and 13N methods were used to assay digested sludge for its potential to denitrify and to reduce nitrate to ammonium. At nitrate concentrations below 10 μM, the reduction of N2O to N2 was not inhibited by acetylene concentrations as high as 80 kPa, though at higher nitrate concentrations acetylene was an effective inhibitor. NO, N2O, and N2 were produces immediately after addition of nitrate or nitrite, indicating that denitrifying enzymes were present. NO was maintained at a concentration of 2–5 nM, while nitrate or nitrite were being reduced, but this gas was depleted once the ionic N oxide substrates were exhausted. Acetylene had little effect on appearance and disappearance of NO. It was also noted that NO was readily consumed by chemical reactions in the anaerobic sludge. Added N2O was reduced without a lag, but pasteurized samples did not consume N2O although they produced it. Fresh digested sludge reduced 60–70% of the added 13NO3− to 13NH4+ with the rest of the NO3−-N presumably lost to denitrification. This agrees well with the nitrate partitioning observed by the acetylene inhibition method in which 30–40% of the NO3−-N was recovered as N2O. Denitrification capacity persisted in both digested sludge and methanogenic enrichment culture which had been grown in a chemostat for 2.5 years with acetate and ammonium as the solid carbon and nitrogen source. This suggests that denitrifiers with capacities for alternative anaerobic energy metabolism may be more common than now known.
Mycoparasitism of sclerotial fungi by Teratosperma oligocladum
Authors: Ayers W. A. , Adams P. B.
Published: May 2010

Sclerotia of Sclerotinia minor were parasitized by Teratosperma oligocladum, a recently described dematiaceous hyphomycete. The mycoparasite was cultured on living sclerotia placed on water agar and on sclerotia in moist sand. It grew poorly on several common laboratory media but growth in vitro was enhanced by supplements of soil extract and, especially, by aqueous extracts of sclerotia. Sclerotia of S. minor, S. sclerotiorum, S. trifoliorum, Sclerotium cepivorum, and Botrytis cinerea were parasitized in vitro, but sclerotia of Sclerotium rolfsii and Macrophomina phaseolina were not. Macroconidia of T. oligocladum germinated on membrane filters placed on soil containing sclerotia of S. minor but not on soil without sclerotia. Sclerotia of three Sclerotinia spp. were infected within 2 weeks in soil infested with the mycoparasite. Teratosperma oligocladum parasitized and destroyed all of the sclerotia of S. minor buried in a natural soil by 10 weeks. Parasitism was equally good at 20 and 25 °C, but occurred more slowly at 15 °C. No parasitic activity occurred at 30 °C. The morphology, cultural characteristics, and mycoparasitic habit of T. oligocladum indicated that it was similar in many respects to the mycoparasite, Sporidesmium sclerotivorum, and that it is a potentially useful agent for the biological control of sclerotial plant pathogens.
Bacteriocin production by Streptococcus salivarius strain P
Authors: Tagg J. R. , Russell C.
Published: May 2010

A bacteriocin, streptococcin sal-P, was isolated by freeze-thaw elution from cultures of Streptococcus salivarius strain P grown on tryptic soy agar plus 1 % neopeptone. The inhibitor could also be extracted with either 7 M urea or 1 M NaCl from cells grown on this medium, but little activity was recovered from cells grown in liquid media or from the supernatants of these cultures. Streptococcin sal-P was found to be a proteinaceous substance of molecular weight approximately 8000. It was remarkably stable at extremes of pH or temperature and appeared to adsorb nonspecifically to both sensitive and resistant bacterial cells and also to cellulose membranes. The range of its inhibitory activity was almost entirely against Gram-positive bacteria, particularly streptococci, including strains of S. pyogenes and S. sanguis, but not S. mutans or group D streptococci. Streptococcin sal-P was bactericidal for actively metabolizing susceptible strains.
Endotrophic sporulation by the yeast Nadsonia fulvescens
Authors: Novak Gary E.
Published: May 2010

Studies of carbon requirements for sporulation by Nadsonia fulvescens showed an unexpected appearance of spores in the absence of an exogenous carbon source, when the cells were grown on ethanol prior to induction of sporulation. Dextrose-grown cells taken from either the logarithmic or stationary phase required a carbon source (dextrose, ethanol, or glycerol) for sporulation. An inhibitory effect by acetate upon sporulation was demonstrated, and it appears to be due to a repression mechanism.
Molecular characterization of Vibrio anguillarum biotype 2
Authors: Schiewe Michael H. , Crosa Jorge H.
Published: May 2010

Examination of polynucleotide sequence relationships among 11 strains of Vibrio anguillarum biotype 2 isolated from moribund fish in North America and Japan demonstrated the highly conserved character of this group of fish pathogens and, moreover, confirmed its discrete nature from V. anguillarum biotype 1. Additional molecular analyses of the V. anguillarum biotype 2 strains revealed the universal presence of a multicopy plasmid with a molecular mass of approximately 20 × 106 daltons and a mole percent guanine plus cytosine of 44. The plasmid of strain DF3K was representative of this molecular species and was designated pMJ101. Subsequent DNA–DNA hybridizations using nick translation-labeled pMJ101 as a probe indicated all the 20 × 106 dalton plasmids were either identical or highly conserved, and, furthermore, that pMJ101 was apparently unrelated to either the virulence plasmid, pJM1, of V. anguillarum biotype 1 or to representatives of common plasmid incompatibility groups. The lack of relatedness between pMJ101 and pJM1 was further supported by differences in their restriction endonuclease cleavage patterns.
Nitrogen fixation and hydrogen metabolism by Rhizobium leguminosarum isolates in pea root nodules
Authors: Nelson Louise M. , Child J. J.
Published: May 2010

A survey of 108 isolates of Rhizobium leguminosarum was conducted to determine the variation in H2 uptake and relative efficiency of N2 fixation in Pisum sativum L. root nodules and the relation of relative efficiency to plant dry weight and N content. Only 14 of the isolates exhibited significant uptake hydrogenase activity and none of these had sufficient hydrogenase activity to recycle all of the H2 produced by nitrogenase. In 74 of the isolates tested relative efficiencies of N2 fixation were less than 0.60.Twenty-nine of the isolates were ineffective, since total plant N at harvest did not differ significantly from uninoculated controls. The remaining 79 effective isolates could be divided into low-and high-efficiency groups. Plants which were inoculated with isolates from the two groups and harvested after 4 weeks did not differ significantly in plant dry weight or N content. Among the isolates with high relative efficiency of N2 fixation, two groups could be recognized: one possessing significant uptake hydrogenase activity, the other lacking hydrogenase activity but in which H2 evolution was low. Although the two groups did not differ with respect to plant dry weight or N content, the identification of this latter group may be of some significance for optimizing the efficiency of N2 fixation.
Some properties of the human erythrocyte receptors for Neisseria gonorrhoeae
Authors: Wiseman G. M. , McNicol P. , Lian C. J. , Primrose D. S.
Published: May 2010

The nature of the receptors for T1 and T4Neisseria gonorrhoeae on erythrocytes and other cells was investigated. In general, cells of nonprimate origin contained few receptors for gonococci. Receptors for T4 gonococci were only uncovered when host cells were pretreated with trypsin. Trypsinization, while unnecessary for T1 adherence to erythrocytes, enhanced attachment in inverse proportion to original erythrocyte sensitivity. Receptors for T1 and T4 organisms on trypsinized and trypsin–neuraminidase-treated erythrocytes were blocked by concanavalin A and peanut lectins, respectively, but a distinction could be made between them with wheat germ lectin and galactose oxidase. Of a number of sugars tested as inhibitors, only D-galactose blocked adherence of T4 but was without effect on T1. While the identity of erythrocyte receptors is uncertain, likely candidates are "band 3" protein and glycophorin, by virtue of their galactose content, lectin binding capacity, and partial exposure on the outer surface of the erythrocyte.
Application of a direct microscopic method for enumeration of substrate-responsive marine bacteria
Authors: Peele E. R. , Colwell R. R.
Published: May 2010

The suitability of a modified acridine orange epifiuorescence technique for direct enumeration of substrate-responsive marine bacteria was evaluated. Seawater samples, incubated with nalidixic acid and various growth substrates, were examined for the presence of enlarged bacterial cells. On average, direct counts of enlarged responsive cells were two orders of magnitude lower than total bacterial numbers as observed by microscopy. The number of swollen cells was found to vary with concentration and type of substrate. Largest direct counts of substrate-responsive cells were obtained in samples incubated with yeast extract or tryptone. Significantly lower counts were obtained in seawater samples incubated with simple carbon or nitrogen sources. Results indicated that growth requirements and substrate preferences of marine bacteria may affect direct microscopic counts of substrate-responsive cells.
Detection of beta-lactamase in Haemophilus influenzae by immunofluorescence
Authors: Hargis Jerold W. , Husain Syd S.
Published: May 2010

Beta-lactamase immunizing antigen was prepared from cells of an ampicillin-resistant strain of Haemophilus influenzae by cold osmotic shock followed by DEAE column fractionation. Nonspecific antibodies were removed by cross-absorption with cells of an ampicillin-sensitive strain of H. influenzae. Any residual nonspecific antibodies remaining after cross-absorption were effectively eliminated by dilution of the anti-beta-lactamase serum 1:50. Twenty strains were tested for presence of beta-lactamase by the indirect fluorescent antibody technique. By this technique 91% of the strains in multiple smears were correctly identified as to the presence or absence of beta-lactamase in a blind study. The beta-lactamases of other gram-negative bacteria were not detectable by this technique.
Uptake and metabolism of organic compounds by Chlorobium phaeobacteroides isolated from Lake Kinneret
Authors: Bergstein T. , Henis Y. , Cavari B. Z.
Published: May 2010

Organic substrates have an important role in Chlorobium phaeobacteroides nutrition, especially under suboptimal light intensities for photosynthetic activity. In addition, increasing acetate concentration in the medium caused a decrease in photosynthetic activity. Approximately 50% of the acetate carbon was retained in the cells, while the other 50% was released as CO2. Acetate carbon and CO2 carbon were assimilated into the same cell fractions. Two key enzymes of the glyoxylic acid cycle were found in Chlorobium cells, indicating that acetate is incorporated via this pathway.
Molecular architecture of the hyphal wall of Achlya ambisexualis Raper. II. Ultrastructural analyses and a proposed model
Authors: Reiskind Julia B. , Mullins J. T.
Published: May 2010

The surface configuration of hyphal walls and various fractions of the wall were analyzed by electron microscopy using carbon–platinum replicas. Fractionation was carried out with both enzymes and chemical solvents. Laminarinase with or without protease and acid with alkali removed the acid- and alkali-soluble glucans revealing an underlying pattern of microfibrils. The combination of cellulase, laminarinase, and protease essentially dissolved the hyphae. The cellulose solvent cadoxen removed the microfibrillar pattern which was exposed following acid and alkali treatment. The acid-soluble fraction is amorphous, the alkali-soluble and the insoluble residuum is faintly microfibrillar, and the cellulose II preparation is strongly microfibrillar. Both the cellulose I and the chitinlike fractions are uniformly microfibrillar. Morphologically, the wall consists of an outer matrix of β-1,3- and β-1,6-glucans covering an inner cellulosic protein core. Both a diagrammatic and molecular model are proposed.
The electron transport chain of Bacterionema matruchotii
Authors: Broom Murray F. , Shepherd Maxwell G. , Sullivan Patrick A.
Published: May 2010

The membrane fraction of Bacterionema matruchotii contains an electron transport chain with oxidizing activity for NADH and succinate. Respiration was inhibited by KCN, 2-heptyl-4-hydroxyquinoline-N-oxide, UV light irradiation and CO. UV light irradiation, analysis of membrane extracts, and reconstitution of respiration in UV light treated membranes suggested that respiration is mediated by a menaquinone derivative. The membranes contained cytochromes a, b, and c. Inhibition studies and the effect of KCN and CO on the cytochrome spectrum indicated the presence of an a + a3 cytochrome oxidase and cytochrome o. The membrane fraction from cells grown under O2-limiting conditions contained nitrate reductase activity. In B. matruchotii, electron transport is coupled to oxidative phosphorylation as judged by the effects of substrates and inhibitors on the intracellular ATP concentration.
Inability to rescue viral genes from human cells biochemically transformed by herpes simplex virus type 2 DNA
Authors: Campione-Piccardo José , Rawls William E.
Published: May 2010

Thymidine kinase negative (TK−) mutants of HSV-1 were used to attempt to rescue HSV-2 genes from cells biochemically transformed with HSV-2 DNA. The results indicate that the occurrence of a rescue event was less than 7 × 10−7 in this system.
Antibodies to snowshoe hare virus of the California group in the snowshoe hare (Lepus americanus) and domestic animal populations of Prince Edward Island
Authors: McFarlane B. L. , Embree J. E. , Embil J. A. , Artsob H. , Weste J. B. , Rozee K. R.
Published: May 2010

This study, the first of arbovirus activity in Prince Edward Island, has shown antibodies to the snowshoe hare strain of the California encephalitis group virus to be present in sera of wild and domestic animals; 15.35% of snowshoe hare, 20% of equine, and 2.5% of bovine sera were positive for hemagglutination inhibition antibody, confirmed by virus neutralization procedures.
Mapping of a new pan mutation in Escherichia coli K-12
Authors: Manch Jean N.
Published: May 2010

A previously unmapped pan gene was localized in an Escherichia coli K-12 strain using Hfr and F′ matings and by transduction studies. This Pan− mutation was shown by supplementation studies to impart a block in pantoate biosynthesis. The pan gene cotransduced with rha, metB, and argE placing it at 87 min.
Growth and cellulolytic activity of Cellulomonas flavigena
Authors: Kim B. H. , Wimpenny J. W. T.
Published: May 2010

Growth factor requirements, growth kinetics, and the ability to produce the enzyme cellulase were examined in the cellulolytic bacterium Cellulomonas flavigena KIST 321. The organism was found to require only thiamine for growth in mineral salts medium containing simple sugars or cellulose. Growth rates on various carbohydrates suggested that disruption of the crystalline structure was the rate-limiting step in the utilization of crystalline cellulose, and hydrolysis of the polymer itself was as rapid as the uptake of the hydrolytic product. When the organism was grown on cellulose the cellulolytic activity appeared to be bound to the cell at the beginning of the exponential growth phase: only after this did cell-free enzyme activity appear. The cell-free enzyme appeared to be unstable, and its activity decreased at the beginning of the stationary phase.
Membrane-associated steroid-binding proteins of Pseudomonas testosteroni
Authors: Francis Mike , Watanabe Mamoru
Published: May 2010

Previous studies have established the presence of periplasmic steroid-binding proteins in induced Pseudomonas testosteroni. This study reports the presence of two additional steroid-binding proteins which can be released from the cytoplasmic membrane during preparation of membrane vesicles. These two proteins differ from each other and from the periplasmic protein in some of their characteristics and steroid specificity, and appear to be distinct from the two membrane-bound steroid dehydrogenases, 3β and 17β-hydroxysteroid dehydrogenase and 1-ene-dehydrogenase.
The seasonal abundance, vertical distribution, and relative microbial biomass of chroococcoid cyanobacteria at a station in southern California coastal waters
Authors: Krempin D. W. , Sullivan C. W.
Published: May 2010

The standing stock of autofluorescent chroococcoid cyanobacteria (1 μm in diameter) paralleled the seasonal trends of phytoplankton and bacterioplankton at a station in southern California coastal waters. Low winter levels increased through the summer to peak levels in the early fall. The greatest number of autofluorescent cells was found within the top 30 m of the photic zone(0.1 × 107 to 7 × 107 cells∙L−1). Numerically, autofluorescent cells accounted for 3% of the total population of prokaryotes, while accounting for 20% of the total prokaryotic biomass. With respect to the total microbial (0.2–203 μm) biomass, the bacterioplankton averaged 5%; autofluorescent cells averaged 1%, with phytoplankton accounting for the remaining 94%.
Effect of Rhizopus oligosporus (NRRL 2710) fermentation on the trypsin inhibitors of black gram (Vigna mungo)
Authors: Kamalakannan V. , Motlag D. B.
Published: May 2010

Solid-state and liquid-state fermentations were carried out to evaluate the effect of Rhizopus oligosporus on the trypsin inhibitor of denatured black gram grits. The trypsin inhibitor fraction was released into the supernatant, attaining a maximum concentration by 72 h of incubation, as indicated by its activity. The increase in trypsin inhibitor activity was approximately threefold in solid-state fermentation and approximately fivefold in liquid-state fermentation. Results indicated that the spore-free culture filtrate prepared from R. oligosporus contained "releasing factor(s)" which were effective on black gram grits. The effect of the spore-free culture filtrate on black gram trypsin inhibitor suggests the presence of a factor in the culture filtrate which inactivates the trypsin inhibitor fraction.
The genome of Bluegill virus
Authors: Robin Jean , Dery Claude
Published: May 2010

The EFDL strain of Bluegill virus, a fish virus, was grown in a Bluegill Fry cell line (BF-2) in medium containing [3H]uridine or [32P]orthophosphate. This virus was purified from the cellular material by precipitation with PEG 6000 followed by isopycnic centrifugation in a Percoll gradient. As calculated from reconstruction experiments, only 8.5 and 0.5%, respectively, of the host proteins and the host RNA were recovered with the viral band, whereas the recovery of viral infectivity was approximately 20%. Electron microscopy of the viral band showed mostly intact virus particles. The nucleic acid extracted from purified virus was found to have the following properties: (i) it migrated homogeneously during electrophoresis at the rate expected from a single-stranded nucleic acid of molecular weight 2.17 × 106, (ii) it sedimentated as a single molecular species when analyzed by velocity centrifugation in sucrose gradients,(iii) it banded in a neutral Cs2SO4 gradient at a density of 1.69 g/cm3 as expected for single-stranded RNA, (iv) its base composition is that of a single-stranded RNA molecule: 14.89% C, 12.77% A, 37.03% U, and 35.23% G. The nucleic acid of Bluegill virus thus appears to be a single-stranded RNA molecule of approximately 2.17 × 106 molecular weight.
Oxidation of aromatic aldehydes and aliphatic secondary alcohols by Hyphomicrobium spp.
Authors: Köhler Jürgen , Schwartz Arnold C.
Published: May 2010

Two of six tested strains of Hyphomicrobium respired on benzaldehyde with higher rates than on formaldehyde, and three strains with equal or lower rates, whereas one strain, Hyphomicrobium X, showed almost negligible respiration on benzaldehyde. Various substituted benzaldehydes stimulated oxygen consumption to lower rates than benzaldehyde itself in active strains. All strains contained multiple forms of dye-linked aldehyde dehydrogenase, as evident from polyacrylamide gel electropherograms of cell-free extracts and activity tests on the gels with nitroblue tetrazolium. All bands of this enzyme reacted more strongly with benzaldehyde than with formaldehyde in all strains. On gels of some strains additional bands appeared with benzaldehyde as the enzyme substrate. Hyphomicrobium X again displayed the lowest activity of this enzyme on the gels. A new band of this enzyme appeared on gels of strain ZV 580 after growth on methylamine, when tested in this respect. NAD-dependent secondary alcohol dehydrogenase was present on gels of three strains, which respired on 2-propanol.Difference spectra and observation of the degree of reduction of ubiquinone and cytochromes b and c of two strains indicated that the electrons from benzaldehyde oxidation were transferred to cytochrome c.The results are discussed with regard to the significance of dye-linked aldehyde dehydrogenases with broad substrate specificity for the catabolism and oligocarbophilic growth of Hyphomicrobium and the taxonomic relevance of the aldehyde dehydrogenase pattern observed on polyacrylamide gel electropherograms.
The cometabolism of 1- and 2-chloronaphthalene by pseudomonads
Authors: Morris Carolyn M. , Barnsley E. A.
Published: May 2010

1-Chloronaphthalene and 2-chloronaphthalene were metabolized by pseudomonads able to degrade naphthalene, but the chloronaphthalenes did not support growth. Their metabolism probably proceeded by the pathway for naphthalene metabolism, for they were not metabolized by cured derivatives of strains in which naphthalene metabolism is normally determined by a plasmid, the metabolism of 2-chloronaphthalene was accompanied by the accumulation of a chloro-2-hydroxy-6-oxohexadienoate, and 4- and 5-chlorosalicylate were converted to this compound and themselves induced enzymes for naphthalene and chloronaphthalene metabolism. In one strain, ATCC 17483, it was possible to show that during growth on succinate in the presence of chloronaphthalenes the enzymes of naphthalene metabolism were induced. Failure of 2-chloronaphthalene to support growth was probably associated with the very slow metabolism of the chloro-2-hydroxy-6-oxohexadienoic acid or possibly with the toxicity of this compound or its metabolites.