bluuebunny/crossref_metadata_2025 huggingface dataset:
The use of fluorescein isothiocyanate in the determination of the bacterial biomass of grassland soil
Authors: Babiuk L. A. , Paul E. A.
Published: February 2010

Quantitative recoveries of bacteria added to a number of soils were obtained using fluorescein isothiocyanate (FITC) as a stain. Enzyme fluorescence, using fluorescein diacetate or dibutyrate, could not be adapted for the routine counting of metabolizing organisms in soil. Staining with rose bengal gave recoveries of 60–80%.Soil-extract dilution plates revealed 4 × 107 bacteria/g in the 0–10 cm layer in April and 27 × 107 in October. One-third of this number was observed in the 20–30 cm layer. Actinomycete colonies added another 20% to the counts at the 0–30 cm depth but constituted 70% of the total colonies from the 90–120 cm depth. Microscopic counts indicated 2.2–4.6 × 109 organisms/g of surface soil. The number of bacteria decreased in a linear fashion with depth but no relation was found between the numbers obtained by direct microscopy and those by plate counting. However, each of the methods showed a high relationship between the size of the bacterial population present at each depth on the different sampling dates.The observed bacteria, actinomycete spores, and hyphal segments averaged 0.6 × 1 μ. On this basis, the biomass in the top 30 cm, as determined by direct microscopy, ranged from 30 to 76 g/m2 (dry weight basis). This implies, considering the amount of available energy, that the individual cells have enough energy to divide only a few times each year. Direct microscopic counting yields a quantitative picture of the organisms present but cannot separate between inactive cells, spores, and metabolizing organisms. Data from plate counts probably give a truer indication of metabolically active cells.
Platelet reactions and immune processes. IV. The inhibition of complement by pyrazole compounds and other inhibitors of platelet reactions
Authors: Jobin François , Gagnon France T.
Published: February 2010

We have found that several inhibitors of the aggregation of human platelets also inhibit guinea pig haemolytic complement (C′). Hydroxyphenylbutazone and sulfinpyrazone were the most potent complement inhibitors among the chemicals studied in this investigation. They inhibited the haemolysis of EAC′142 by EDTA-C′. Chloroquine and hydroxychloroquine also inhibited complement. It is suggested that drugs which could inhibit both platelets and complement might prove beneficial in the treatment of thrombo-immuno-inflammatory conditions.
Characteristics of pectate lyase formation by Hypomyces solani f. sp. cucurbitae
Authors: Hancock Joseph G. , Eldridge Colleen , Alexander Michal
Published: February 2010

Pectate lyase, produced by Hypomyces (Fusarium) solani f. sp. cucurbitae, is considered a normal extracellular enzyme in that most of the enzyme was found in the culture medium during early stages of enzyme production and before extensive lysis. This enzyme was produced during active growth in the presence of citrus pectate but not citrus pectin. Enzyme yield was highest when the initial pH of the medium was between 5.5 and 7.5 and the temperature was between 25 and 29 C. Production of the enzyme was reduced when individual amino acids or inorganic N-sources were substituted for casein hydrolyzates. Glucose repressed enzyme formation when it exceeded 0.025%, while arabinose and xylose had little effect or stimulated greater production at 0.1%. Pectate lyase yield varied considerably, depending on fungus strain and inoculum level used. A delay in enzyme formation was reduced substantially when small amounts of agar were present in the liquid medium or the medium was solidified with agar.
Penetrability of a marine pseudomonad by inulin, sucrose, and glycerol and its relation to the mechanism of lysis
Authors: Buckmire Francis L. A. , MacLeod Robert A.
Published: February 2010

Cells of a marine pseudomonad were prevented from lysing when suspended in a 0.15 M sucrose solution even after treatment of the sucrose with an ion exchange resin to remove contaminating trace elements. Isolated cell envelopes of the organism in concentrations of sucrose able to prevent lysis of the cells released non-dialyzable hexosamine-containing material into the suspending medium. This did not occur when the envelopes were suspended in concentrations of NaCl able to prevent cell lysis. Glycerol was found to occupy almost all the available fluid space in a packed cell preparation of the organism. Sucrose occupied less space than glycerol, and inulin the least. When the sucrose concentration was increased from 3 mM to 0.2 M, both the sucrose and inulin spaces increased. The results have been interpreted as indicating that sucrose prevents lysis by balancing the internal osmotic pressure of the cells, that the various layers of the cell envelope of the organism differ in their permeability to various solutes, and that the whole cell shrinks in solutions of high osmotic pressure.
Serological characteristics of Streptomyces species using cell wall immunizing antigens
Authors: Taylor Gerald R. , Guthrie Rufus K. , Shirling Elwood B.
Published: February 2010

A dichotomous key for determination of serological groups among Streptomyces is described. This key is limited in that only seven specific antisera are used for testing. The utility and reliability of the application of this key were tested and compared to the results of previous taxonomic studies reported on the basis of biochemical and morphological characteristics of these organisms. Results indicate the desirability of using a combination of methods including serological characteristics on the one hand, and biochemical–morphological characteristics on the other, to increase the reliability of taxonomic studies.
The effects of serum components on the agglutination of Gram-negative bacteria
Authors: Melching L. , Vas S. I.
Published: February 2010

Fresh normal guinea pig serum was found to increase the agglutination titer of antiserum. Absorption of fresh serum with homologous bacterial cells did not remove the activity. Exposure of fresh serum to 56 C for 30 min, 0.01 M ethylenediaminetetraacetic acid (EDTA), or 150 μg/ml of lipopolysaccharide significantly decreased its activity. This reaction was shown to be initiated at 37 C, but not at 0 C, thus indicating an enzymatic reaction, possibly that of the complement system. Other sources of fresh serum were also found to mediate this reaction. Although this phenomenon requires further investigation, it should be considered when evaluating the bactericidal effect of serum from plate counts, as some decrease in numbers could be due to agglutination.
The interaction of Coxiella burnetii phase I and phase II in Earle's cells
Authors: Kordová Nonna , Burton Paul R. , Downs Cora M. , Paretsky David , Kováčová Elena
Published: February 2010

Coxiella burnetii (Cb) in phase I (Ph I) multiplies very poorly in L-cells as shown by light and electron microscopy and infectivity titrations; Cb antigens, however, are detectable by immunofluorescence in most cells. Phase II (Ph II) organisms, in contrast, multiply well and produce typical particles in well-defined cytoplasmic vacuoles. Density gradient centrifugation has been applied to test the heterogeneity of the animal-maintained Nine Mile strain in Ph I and the corresponding egg-grown strain in Ph II. The evidence indicates that both strains are mixtures of Ph I and Ph II organisms, although they reacted as Ph I or Ph II antigens in the complement fixation test. The interaction of Ph I and Ph II organisms was studied in mixed infections in L-cells; suppression, or a less marked enhancement, of the growth of Coxiella burnetii was observed, depending on the conditions. It is suggested that Ph I and Ph II rickettsiae represent genetically different but closely related organisms, Ph I being the "parent" strain and Ph II the "mutant" strain; "phase variation" of Coxiella burnetii results from a selection of the mutant in the population under the prevailing environmental conditions.
Influence du mode de culture dans la toxinogénèse de Plectridium tetani
Authors: Vinet G. , Fredette V.
Published: February 2010

Production of tetanus toxin under strictly anaerobic conditions does not favor high titers comparable to those obtained when the surface of the culture medium is largely exposed to the air.
Biosynthesis of cinnamamide and detection of phenylalanine ammonia-lyase in Streptomyces verticillatus
Authors: Bezanson G. S. , Desaty D. , Emes A. V. , Vining L. C.
Published: February 2010

Radioactivity from L-phenylalanine-carboxyl-14C was incorporated specifically into the carboxyl group of cinnamamide by cultures of Streptomyces verticillatus. L-Phenylalanine ammonia-lyase (EC. 4.3.1.5) could be extracted from the mycelium. Cultures grown in defined medium produced little cinnamamide unless supplemented with L-phenylalanine; phenylalanine ammonia-lyase activity in the mycelium was directly related to the yield of cinnamamide.
Changes in the rhizosphere microflora of spring wheat induced by disomic substitution of a chromosome
Authors: Neal Jr. J. L. , Atkinson T. G. , Larson Ruby I.
Published: February 2010

Substitution of a chromosome pair (5B) from Apex (A), a variety of spring wheat (Triticum aestivum) relatively resistant to common root rot (primarily Cochliobolus sativus), for the corresponding chromosome of S-615 (S), a highly susceptible variety, changed the rhizosphere microflora qualitatively and quantitatively. Microbial analyses of the parental varieties, the substitution line (S-A5B), and non-rhizosphere soil included estimates of total microbial populations and physiological and nutritional groupings. In all characteristics a typical rhizosphere effect was evident, and significant differences were found between the different rhizospheres. In most characteristics the rhizosphere microflora of the substitution line was significantly different from either parent. The incidence of rhizosphere bacteria antagonistic to C. sativus was the most notable exception. Twenty percent of the rhizosphere isolates from both Apex and the resistant substitution line S-A5B were antagonistic to C. sativus. None of the isolates from the susceptible variety was antagonistic. The differences between the rhizospheres of the substitution line (S-A5B) and the recipient variety (S-615) are attributable to changes induced by disomic substitution of chromosome 5B.
Activity and location of two enzyme fractions during the culture cycle of Schizosaccharomyces pombe
Authors: Rock Gail Dolan , Johnson B. F.
Published: February 2010

When cell walls of Schizosaccharomyces pombe were removed, the protoplast contained most of the ribonuclease but only about 50% of the aminopeptidase activity. In cell homogenates approximately 75% of the total peptidase activity was in the soluble fraction; the membrane fraction retained an average of 25% while the ribosomes had less than 1% of the total activity. The RNase activity was highest in stationary phase, aminopeptidase at mid log phase. Properties of the soluble aminopeptidase were similar in many respects to those of the enzyme from Escherichia coli. In contrast, 90% of the ribonuclease activity was attached to the membrane fraction and up to 10% was found on the ribosomes. The ribosome-bound ribonuclease required incubation in 4 M urea for activation; however, the purified ribonuclease had properties similar to the ribonuclease I of E. coli.
Soil bacteria: numerical analysis of electrophoretic protein patterns developed in acrylamide gels
Authors: Rouatt J. W. , Skyring G. W. , Purkayastha Vesna , Quadling C.
Published: February 2010

The protein band patterns of 47 soil bacteria, all thought to be of the arthrobacter kind, were analyzed by a simple numerical method in which each observed Et value was treated as a unit character. The results were not satisfactory. In a second analysis only major bands were taken into account and small variations in the Et values of the 24 chosen bands were disregarded. This subjective editing was required to satisfy a minimum criterion that replicates be recognized as such by the analysis. It was concluded that without a means of estimating the variation in Et value for each band and of identifying homologous bands, electrophoretic band patterns of crude extracts of soluble proteins are likely to be of limited rather than general use in microbial taxonomy.
A freeze-etch study of membranes in the yeast Wickerhamia fluorescens
Authors: Bauer Heinz
Published: February 2010

In this study the surface structure of the plasmalemma, the endoplasmic reticulum, and the vacuolar membrane of the yeast Wickerhamia fluorescens was examined by freeze-etching. The outer surface of the plasmalemma is covered with densely packed globular units, 100 Å in diameter, which, in some places, are arranged in a hexagonal pattern with the centers of the particles spaced 150 Å apart. The highest number of particles per unit membrane area can be observed in cells approaching the end of the logarithmic growth phase.To the outer surface of the endoplasmic reticulum (ER) are attached 50 Å units and, in cells approaching the stationary growth phase, about 10% of these particles are arranged in long double rows resembling membrane-bound chains of polyribosomes. Fewer, but larger, particles of the same order of size as those on the plasma membrane are randomly distributed over the inner surface of membranes of the ER.The outer surface of the membrane surrounding the vacuole bears the same size of particles (50 Å) as the outer surfaces of the ER, confirming the theory according to which vacuoles may be regarded as differentiations of the ER.
A fermenter for plant cell suspension cultures
Authors: Veliky I. A. , Martin S. M.
Published: February 2010

A conical glass V-fermenter for plant cell suspension cultures is described. This V-fermenter has proved useful for the production of biomass and metabolic products. It also is ideally suited for the preparation and maintenance of actively growing cultures to be used as inocula for shake flasks and fermenters. An outline of the procedure for isolating and "conditioning" plant cell suspension cultures is presented.
Biotin deficiency in Arthrobacter globiformis: fine structure and effect of physical stress
Authors: Robertson Janet , Chan E. C. S.
Published: February 2010

The minimal biotin requirement for both maximum growth and normal morphological development of Arthrobacter globiformis 425 was found to be about 0.3 ng/ml medium. Morphological changes associated with biotin nutrition were investigated by light and electron microscopy. The aberrant form induced by biotin deficiency consisted of several membrane-bound bodies embedded in a thick matrix which appeared distinct from the wall of the normal organism. Both cell types resisted lysis by tonicity changes but the aberrant form showed greater resistance than the normal cell to destruction by sonication.
Detection of latent murine nosematosis and growth of Nosema cuniculi in cell cultures
Authors: Bismanis J. E.
Published: February 2010

Administration of hydrocortisone to mice caused activation of latent nosematosis in at least 25% of the animals. The sporozoan parasite Nosema cuniculi could be demonstrated in the tissues of the internal organs and circulating blood by direct microscopic examination. Growth and multiplication of the parasite could be achieved in mouse embryo cell cultures, where the parasite infected and destroyed only about 2% of the cells, thus establishing a state of persistently infected cell culture. The parasite grown in cell culture retained its mouse pathogenicity.
Physiology of sporeforming bacteria associated with insects. I. Glucose catabolism in vegetative cells
Authors: Bulla L. A. , Julian G. St. , Rhodes R. A. , Hesseltine C. W.
Published: February 2010

The catabolic pathways for use of glucose in proliferating vegetative cells of Bacillus thuringiensis, B. alvei, B. lentimorbus, and B. popilliae were studied by radiorespirometry. These organisms dissimilate glucose predominately via the Embden–Meyerhof–Parnas pathway and to a lesser extent by the pentose phosphate pathway. Extent of participation of concurrent pathways varied with each organism. Tentative evidence suggests that B. popilliae and B. lentimorbus, grown in a yeast extract – glucose medium, lack a fully operational tricarboxylic acid (TCA) cycle. Dilution of this medium slightly enhanced TCA cycle activity in B. popilliae but had no effect with B. lentimorbus. Radiorespirometric data regarding glutamic acid oxidation also were obtained for each bacterium. All organisms studied except B. lentimorbus were capable of oxidizing glutamic acid to carbon dioxide.
Composition of the cell wall of Pityrosporum ovale (Bizzozero) Castellani and Chalmers
Authors: Thompson E. , Colvin J. Ross
Published: February 2010

Fractions of the cell wall of the yeast, Pityrosporum ovale, were analyzed for neutral sugars, nitrogen, protein, hexosamines, cysteine + cystine, lipids, and ash as affected by age of cells and degree of breakage of cells. Neither the age of cells nor the degree of breakage influenced the composition of the fractions very much. The results indicate that the composition of the wall of P. ovale is substantially different from that of Saccharomyces cerevisiae, being higher in lipid, protein, and glucosamine. The polymerized N-acetyl-glucosamine in the wall seems to be present in a non-crystalline form. These results are consistent with known structural differences between the walls of the two genera.
A plant wilting factor from Rhizobium spp.
Authors: Hubbell D. H.
Published: February 2010

The ability of crude preparations of extracellular polysaccharide from Rhizobium species to induce plant wilting in vitro is reported for the first time.
Nucleic acid homology as a measure of genetic compatibility among streptococci and a strain of Diplococcus pneumoniae
Authors: Mehta Bipin M. , Hutchison Dorris J.
Published: February 2010

A correlation has been observed between the degree of DNA–DNA (deoxyribonucleic acid) hybridization and the frequency of interspecific genetic transformation between Streptococcus species of serological groups D and H and Diplococcus pneumoniae. The thermal denaturation (Tm) values and guanine plus cytosine (G + C) mole percent for all cultures were similar. Two mutants of the group D streptococcus, resistant to the potent antileukemic drug amethopterin, were found to be more alike than any other two organisms studied. The intraspecific genetic transfer of the thymine-requirement marker in either direction was not successfully demonstrated. The lack of transformation of amethopterin resistance to the wild type organism was partially due to the lack of homology between the mutants and the wild type.
Evidence for muramic acid in soil
Authors: Millar W. N. , Casida Jr. L. E.
Published: February 2010

Evidence indicative of the presence of muramic acid in soil was demonstrated. Muramic acid values ranging from 0 to 150 μg/g dry weight of soil were obtained for 33 different soil samples. Comparisons of these values with the muramic acid contents of laboratory-grown microbial cultures revealed that the soil muramic acid levels are about 100- to 1000-fold greater than can be accounted for by a platable bacterial population in soil, but are compatible with other estimates of total bacterial soil numbers. It was suggested that a muramic acid analysis of soil might provide an estimate of its total bacterial population.
The degradation of p-toluenesulfonate by a Pseudomonas
Authors: Focht D. D. , Williams F. D.
Published: February 2010

A Pseudomonas isolated from sewage was adapted to use p-toluenesulfonate as the sole source of both carbon and sulfur. Very few of over 30 aromatic compounds tested were used for growth as sole carbon sources. Significantly, sulfobenzoate, phenolsulfonates, and isomers of cresolsulfonates did not support growth. Respirometry studies with washed, resting cells showed similar results. In both studies, benzenesulfonate was always used more rapidly than p-toluenesulfonate. The degradation of p-toluenesulfonate was shown to be over 90% of the theoretical value required for complete mineralization to carbon dioxide, water, and sulfate. When resting cells were incubated with 35S-p-toluenesulfonate, the ratio of oxygen uptake to 35S-sulfate liberation remained constant during the complete degradation period. Radiochromatographic analysis showed no 35S-aromatic intermediates in resting-cell supernatants at any time. Resting cells previously incubated with 35S-p-toluenesulfonate liberated two 35S-labeled aromatic intermediates upon disruption. Resting cells incubated with 1-14C-p-toluenesulfonate produced labeled 3-methylcatechol, labeled acetate, and unlabeled pyruvate. The labeled intermediate, 3-methylcatechol, was degraded by cell-free extracts to labeled acetate. Hydroxylation, desulfonation, ring cleavage, and subsequent fissions of the carbon chain occurred in that order; all steps but the first were catalyzed by cell-free extracts.
Inhibition of cell division in Micrococcus lysodeikticus dis-II
Authors: Grula E. A. , King Robert D.
Published: February 2010

A strain of Micrococcus lysodeikticus (designated dis-II) has been isolated by nutritional selection using aspartic acid as the major source of carbon, nitrogen, and energy. This organism is inhibited from dividing when grown in a defined medium in the presence of D-serine, penicillin, mitomycin c or under conditions of suboptimal magnesium concentration. All of the division-inhibiting compounds decrease growth yields and induce varying amounts of lysis. L-Lysine, when added to D-serine-containing media, allows some increase in growth yields, but division inhibition appears more pronounced. Pantoyl lactone, D- and L-alanine, and to a lesser extent Carbowax 400 (hypertonic conditions) and glycine, but not spermine, will significantly prevent but not reverse division inhibition in D-serine-lysine-containing media. Thin-slicing and electron microscopic observation of non-dividing cells shows that a relatively thick layer of porous-appearing cell wall mucopeptide is synthesized when cells are grown in the presence of D-serine. These cells as well as those grown in the presence of penicillin or mitomycin c are not lysed in distilled water. Amount of cell wall mucopeptide is greatly decreased in cells grown under conditions of suboptimal magnesium concentration; these cells undergo extensive lysis in distilled water.
Some characteristics of streptococci competent for uptake of deoxyribonucleic acid
Authors: Pakula R. , Ray P. , Spencer L. R.
Published: February 2010

The degree of competence for uptake of deoxyribonucleic acid (DNA uptake) of the Challis streptococcus was found to be strictly related to the concentration of cell-bound competence-provoking factor (CPF). Antibodies against competent cells and antibodies against crude concentrates of CPF inhibited DNA uptake by competent cells. Both types of antibodies interacted also with soluble CPF and reduced its capacity to induce competence. Two characteristic features of competent streptococci were revealed: high precipitability at low pH's and a reduced capacity to absorb methylene blue.
Characterization of saccharolytic nonfermentative bacteria associated with man
Authors: Pickett M. J. , Pedersen Margaret M.
Published: February 2010

Features of 378 clinical isolates of saccharolytic, nonfermentative Gram-negative rods and 20 reference strains were examined. All but four of the clinical strains were assigned to recognized taxa, namely Acinetobacter, Chromobacterium, Flavobacterium, Pseudomonas aeruginosa, Pseudomonas fluorescens, Pseudomonas maltophilia, Pseudomonas multivorans, Pseudomonas putida, Pseudomonas stutzeri, and Xanthomonas.
Enzymatic and 14C-mannitol studies of the Aspergillus mannitol metabolism
Authors: Lee Wei Hwa
Published: February 2010

Aspergillus species (UC4177) accumulated mannitol from glucose substrate and it also used mannitol as the sole carbon source. Experiment with radioactive mannitol showed that the accumulation of mannitol and the oxidation of mannitol to CO2 proceeded simultaneously. The presence of glucose in the medium did not inhibit mannitol oxidation. Mannitol was oxidized at about 25% of the metabolic rate of glucose. The rate of mannitol oxidation and several of the enzymes directly involved in mannitol metabolism were unaffected by using glucose or mannitol as the sole source of carbon. Nine enzymes of glucose metabolism were tested and none appeared to limit the rate of glucose oxidation. Aspergillus phosphofructokinase was not inhibited by 2.4 mM ATP or 10 mM citrate. Possible enzymatic defects favoring mannitol accumulation were not found.
Tumors induced in hamsters by a respiratory-associated canine adenovirus (A26/61)
Authors: Dulac G. C. , Swango L. J. , Burnstein T.
Published: February 2010

Sarcomas were induced in the subcutis of hamsters by a respiratory-associated (RA) canine adenovirus, A26/61. The tumors were transplantable in vivo and retained their oncogenic properties after in vitro cultivation. Hamsters bearing RA-induced tumors developed complement-fixing antibodies against T antigens prepared in cell culture. The sera reacted to a lesser degree with T antigens induced by infectious canine hepatitis (ICH) virus, but not with those induced by an unrelated simian adenovirus.
Salient features of nonsaccharolytic and weakly saccharolytic nonfermentative rods
Authors: Pickett M. J. , Pedersen Margaret M.
Published: February 2010

One hundred and thirty-one strains of nonsaccharolytic and weakly saccharolytic Gram-negative rods recently isolated from clinical specimens were examined with a battery of 74 tests, mostly biochemical. All but five of these strains were thus assigned to established taxa. Alkalinization of amides and organic acids was a particularly useful feature for identifying these bacteria.
Ultrastructure of Vi phages I to VII of Salmonella typhi
Authors: Ackermann H. -W. , Berthiaume L. , Kasatiya S. S.
Published: February 2010

Vi phages I to VII belong to three morphological groups. All phage heads are octahedral. The tail of phage I is long and contractile, whereas that of phage II is long and sheathless. Phages III, V, VI, and VII have very short tails and are nearly identical in morphology and dimensions. Preparations of phage IV supplied by three typing centers contain two distinct phages resembling either phage I or III. It seems necessary to study the morphology of typing phages for control purposes.
The toxicity of cochliodinol, an antibiotic metabolite of Chaetomium spp.
Authors: Brewer D. , Jerram W. A. , Meiler D. , Taylor A.
Published: February 2010

Cochliodinol is a phenol of unknown structure and a metabolite of Chaetomium cochliodes and C. globosum. It inhibited the growth of some species of several genera of microfungi at concentrations of 1–10 μg/ml. The germination of spores of Botrytis allii and Fusarium moniliforme was also inhibited, at similar concentrations. Cochliodinol forms stable, insoluble salts with strong bases but the triethanolamine salt is appreciably soluble in water. Solutions of this salt inhibit the growth of many species of bacteria. The growth of several strains of Pseudomonas aeruginosa isolated from the local general hospital was inhibited at 30 μg/ml. Cytopathological effects were not observed in cultures of HeLa cells at 5 μg/ml and preliminary toxicity tests in young turkeys and rats did not reveal symptoms of acute toxicity.
Preservation of viable flexibacteria at low temperatures
Authors: Sanfilippo Annika , Lewin Ralph A.
Published: February 2010

Most of the 28 species (91 strains) of flexibacteria tested without additives survived after freezing in liquid nitrogen (−196 °C): they included all six Microscilla spp., all three Cytophaga spp., both of the Herpetosiphon spp. tested, Flexithrix dorotheae, and seven (most strains) of the eight species of Flexibacter spp. All but 2 of the 19 strains of Saprospira grandis, but neither of the two other tested species of Saprospira, survived freezing to −196° without additives.Incorporation of 10% glycerol before freezing permitted survival of three of the sensitive strains of Flexibacter (F. aurantiacus copepodarum, F. flexilis iolanthae, and F. giganteus), but adversely affected two other species (F. elegans and F. ruber). Incorporation of 10% dimethyl sulphoxide (DMSO) had some similar effects. Freezing to −196° with glycerol conserved viable cultures of all 19 S. grandis strains, of S. toviformis, and of 2 of the 3 strains of S. thermalis.A less extreme temperature was less satisfactory. Stored at −22°, some or all strains of 6 species died out in less than 1 week; most strains of 12 others died after a few weeks; and 7 species survived for at least 21 weeks. (The other three were not tested.)
Proton magnetic resonance spectra of the mannans of some new species of Hansenula and their phylogenetic significance
Authors: Spencer J. F. T. , Gorin P. A. J. , Wickerham L. J.
Published: February 2010

The proton magnetic resonance spectra of the mannose-containing polysaccharides from some new species of Hansenula were obtained and used as an aid in establishing their phylogenetic relationships to other members of the genus. The spectrum of the mannan from Hansenula dimennae is identical with that of the mannan from Hansenula californica. These two haploid species are taxonomically closely related and are adjacent on the same line of the phylogenetic diagram according to Wickerham. Hansenula saturnus var. subsufficiens mannan has a spectrum like those of the mannans of some strains of Hansenula mrakii and Hansenula beijerinckii. The new species Hansenula henricii, Hansenula nonfermentans, and Hansenula glucozyma all form mannans with spectra having characteristic signals at about τ4.24 and τ4.38, as do the spectra of the mannans formed by the other species on the same phylogenetic line, Hansenula polymorpha, Hansenula minuta, and Hansenula wickerhamii. These species have, relatively, DNA's with the highest guanine and cytosine percentages in the genus. Hansenula platypodis, a species which, unlike other Hansenula species, forms ascophores and anastomoses, has DNA with a lower content of guanine plus cytosine. The spectrum of H. platypodis mannan is like that of H. minuta mannan, with the exception of two small signals at τ4.44 and τ4.48 which do not occur in the spectrum of H. minuta mannan.
Effects of radiation pasteurization on Salmonella. I. Parameters affecting survival and recovery from chicken
Authors: Previte Joseph J. , Chang Y. , El-Bisi H. M.
Published: February 2010

Growth of Salmonella typhimurium, strain RIA, in minimal broth supplemented with methionine, produced a population of cells that was more sensitive to 60Co irradiation than were those grown in brain heart infusion. The resistance values (D) were 0.056 and 0.066 Mrad, respectively. D was not significantly different when the bacteria were irradiated at 4 °C on fresh or frozen-thawed germ-free chicken, or on conventional chicken sterilized by autoclaving, or by exposure to 2 Mrad of ionizing radiation. It was generally higher when the cells were irradiated in the original growth medium than on chicken. D of five different strains of S. typhimurium irradiated at 4 °C on autoclaved chicken varied from 0.052 to 0.068 Mrad. The greatest increase in resistance was produced by decreasing the temperature during irradiation. S. typhimurium, RIA, attained a D value of 0.293 Mrad at −80 °C. The effect of the recovery media on survival is equivocal. In some instances nutrient and minimal agar seemed to provide slightly better recovery of strains SR-11 and RIA. Enrichment of complex media with yeast extract did not increase recovery. The results indicate that of those parameters studied, the most significant effects on resistance were due to the temperature during irradiation.
Effect of tryptophan on alkaloid biosynthesis in cultures of a Claviceps species
Authors: Vining L. C.
Published: February 2010

Addition of tryptophan to cultures of Claviceps strain HLX 123 caused a large increase in alkaloid production. For maximum effect a supplement of at least 250 mg/l was required within 1 day after inoculation. When L-tryptophan-β-14C was used the labeled amino acid accumulated in the mycelium until alkaloid synthesis began, near the end of the growth phase. Intracellular tryptophan was then rapidly incorporated into alkaloids which were excreted into the culture fluid. L-Tryptophan-β-14C added to cultures during the period of rapid alkaloid synthesis was efficiently incorporated into alkaloids, but caused only a small increase in yield. The results suggest that tryptophan stimulates alkaloid production mainly through an increase in activity of the alkaloid-synthesizing enzyme system. The role of tryptophan in the regulatory process is discussed.
Studies on the purification of Entamoeba histolytica antigens by gel filtration. I. Some physicochemical properties of the isolated fractions
Authors: Khan Z. Ali , Meerovitch E.
Published: February 2010

Aqueous extracts, prepared from Entamoeba histolytica (DKB strain) grown at 37 °C in TTY medium with Crithidia sp., were chromatographed on Sephadex G-200 and G-100 gels equilibrated with 0.15 M phosphate buffer, pH 7.2. Seven fractions were obtained, the molecular weights of which ranged from 650 000 to [Formula: see text]. The absorption spectra of either the whole amoebic extract or the first two fractions from the G-200 column were in the region of 280 mμ. The protein to carbohydrate ratio of the whole undialyzed amoebic extract was 2.6:1, which changed to 17:1 after dialysis, indicating a considerable loss of carbohydrate. The whole amoebic extract when subjected to disc electrophoresis resolved into 26 protein bands while the fractions, in addition to having contaminants from the preceding peaks, also contained their own characteristic protein bands. The first two fractions contained, as determined by disc electrophoresis and isoelectric focusing, a variety of different anionic proteins. The isoelectric pH of the first fraction was 5.8 to 6.0 and that of the second ranged between 4.5 and 6.4.
Studies on the purification of Entamoeba histolytica antigens by gel filtration. II. The antigenic properties of the isolated fractions
Authors: Khan Z. Ali , Meerovitch E.
Published: February 2010

Partially purified fractions of the water-soluble extract of Entamoeba histolytica (DKB strain) obtained by chromatography in Sephadex G-200 (F1, F2, and F4) and G-100 (F3a, F3b, F3c, and F3d) gels were used in various serological tests and their reactivities compared with the whole 1:40 antigen. The main haemagglutinating (HA) and complement-fixing (CF) activities were confined to fractions F1 and F2, which had molecular weights of 650 000 and 229 000, respectively. The 4 to 6 μg/ml of protein contained in these fractions at the optimum dilution gave antibody liters comparable to those for the whole antigen, which had about 77 μg/ml of protein. The other antigen fractions (F4, F3a, F3b, F3c, and F3d) showed very little activity. Fraction F1 had two main precipitin bands (1 and 2), which showed reaction of identity with two of the bands in fraction F2. The other fractions which showed some HA and CF reactivity had trace amounts of these antigens. It is presumed that the antigens specific for precipitin bands 1 and 2 are the main CF and HA antigens.
Requirements for transformation of the Challis streptococcus
Authors: Pakula R. , Ray P.
Published: February 2010

Transformation of the group H streptococcus Challis was studied in a mixture of phosphate buffer and glucose supplemented with either free amino acids or nondialyzable peptides or both ingredients. Peptides were a requisite for development of competence. Marker integration and phenotypic expression of the acquired streptomycin-resistance character occurred when either peptides or amino acids were present in the medium. The yield of transformants, however, was optimal when both were available during the entire process of transformation.
Saprospira toviformis nov. spec. (Flexibacterales) from a New Zealand seashore
Authors: Lewin Ralph A. , Mandel Manley
Published: February 2010

A new species of flexibacterium, Saprospira toviformis, is described. It was isolated from marine littoral sand from New Zealand. It differs from S. grandis Gross by its more yellow color, more sluggish motility, and a number of minor physiological features. The content of guanine and cytosine, in the DNA of S. toviformis is 38% (as molar percent); the corresponding value for S. grandis is 48%.
Flexithrix dorotheae gen. et sp. nov. (Flexibacterales); and suggestions for reclassifying sheathed bacteria
Authors: Lewin Ralph A.
Published: February 2010

Flexithrix dorotheae gen. et sp. nov. (Flexibacterales) is described. It was isolated in pure culture from seashore silt at Ernakulum, Kerala, India. It is characterized by sheathed filaments of indefinite length and false branching; dispersal is by flexuous, gliding cells. It requires no specific organic factor for growth. Other physiological and nutritional data are presented. The cells contain quantities of the carotenoid, zeaxanthin. The deoxyribonucleic acid contains 37% guanine + cytosine. Consideration of the implications of sheath formation in bacterial taxonomy suggests that the order Chlamydobacteriales be abandoned.
Flagellar bundles of the honeybee pathogen, Bacillus larvae; their occurrence, size, and development in vivo and in vitro
Authors: Wilson W. T. , Combs L. E.
Published: February 2010

Flagellar bundles of the honeybee pathogen, Bacillus larvae, occurred in vivo and in vitro. Bundles as large as 47.5 × 0.6 μ developed in the gut contents of young honeybee larvae from 48 to 72 h after ingestion of spores. In vitro, they were produced in two types of media, and were seen as early as 24 h after the initiation of vegetative growth. Flagellar bundle formation was not related to sporulation.In stained sections of honeybee larvae infected with B. larvae, vegetative cells had a peritrichous coat of flagella which was apparently shed at a specific stage in the growth of the pathogen. It is probable that the release of a single flagellum or a coat of flagella is biochemically initiated both in vivo and in vitro.
Radiobacterphage neutralization anomaly in relation to cations
Authors: Roslycky E. B.
Published: February 2010

Antiserum neutralization of PS-192 and PR-1001 bacteriophages of Agrobacterium radiobacter produced anomalous and first-order inactivation curves, respectively. Maximum neutralization rates were obtained with about 0.1 M NaCl solution. Neutralization velocity constants (K values) with the PR-1001: SPR-1001(3) system in 0.1 M of Na+, K+, Li+, Cs+, and NH4+ were 24, 28, 23, 22, and 22, respectively. Bacteriophage neutralization was suppressed by 0.01 M concentration of eight divalent cations in the presence of 0.1 M NaCl solution. Differences in the Na+, K+, Ca2+, and Mg2+ concentrations in sera of 12 rabbits ranged up to 31, 61, 18, and 22% respectively. Small amounts of Ca2+ intensified the anomaly observed with phage PS-192. This cation also produced a deviation from a first-order neutralization ordinarily characteristic for the PR-1001: SPR-1001(6) phage: antiserum system. A small concentration of Na-citrate, which exerted no detrimental effect on phage PS-192, corrected the anomaly usually typical for PS-192: PR-1001(6) system. These findings suggest that as the neutralization proceeds the cation concentration in the reaction mixture may gradually increase as a result of antigen: antibody union, thus bringing about a progressive deceleration in the rate of radiobacterphage neutralization.
2,5-Dihydrophenylalanine as an inhibitor of microbial growth
Authors: Genghof Dorothy S.
Published: February 2010

DL-2,5-Dihydrophenylalanine (DHPA) inhibited the growth of a variety of bacteria representing 10 different genera. Three yeasts were also sensitive to DHPA but only two of nine filamentous fungi were inhibited. The relative effectiveness of DHPA isomers as growth antagonists for S. cerevisiae and E. coli has also been investigated, and, on a molecular basis, DL-DHPA was found to be half as effective as L-DHPA against both of these microorganisms. This DHPA inhibition was reversed by addition of equimolar amounts of phenylalanine. Acetyl derivatives of L-DHPA and DL-DHPA were only slightly inhibitory for S. cerevisiae. A synergistic effect on the DHPA-induced growth inhibition of S. cerevisiae was observed when tyrosine was added to the medium.
Effects of mechanical shaking and water tension on survival and distribution of fungal inoculum in glass microbead media
Authors: Dickinson C. H. , Parkinson D.
Published: February 2010

Data are given on two aspects of the study of fungi in glass microbead systems. Using two fungi (Penicillium decumbens and Cylindrocarpon destructans) the effect of shaking on microbead–water–spore suspensions was studied and it was shown that such shaking causes extensive killing of fungal spores (this effect being much greater for spores of P. decumbens than for spores of C. destructans). Using the same fungi, the effect of moisture tension on movement of spores was studied and data are given showing that the spores may move considerable distances during changes in water tension, this movement being limited by spore and pore size.
Cellulolytic activity in municipal solid waste composting
Authors: Stutzenberger F. J. , Kaufman A. J. , Lossin R. D.
Published: February 2010

A study was made of the open windrow method of municipal solid waste composting as related to those factors that might influence cellulose decomposition. Composting temperatures reached a maximum (55–65 °C) at 3 weeks and then gradually decreased during the rest of the 49-day process. The pH values of compost samples homogenized in distilled water decreased slightly during the initial stages of the process and then increased gradually to final values of 7.0–8.5. Clarified compost extracts were assayed for cellulase activity by measuring the hydrolysis rate of carboxymethylcellulose (CMC). Maximal cellulase activity occurred at 65 °C, pH 6.0, with a CMC concentration of 2.5%. The cellulase activity of compost increased 10-fold at a logarithmic rate while the cellulose content decreased 50%. In a preliminary search for microorganisms active in cellulose degradation during the composting process, three cellulolytic species were isolated; these were identified as Aspergillus fumigatus, a Bacillus species, and a Thermoactinomyces species of the Actinobifida group.
Sorption of water by spores, heat-killed spores, and vegetative cells
Authors: Grecz Nicholas , Smith Roberta F. , Hoffmann Charles C.
Published: February 2010

Several hypotheses explain the heat resistance of bacterial spores in terms of a hydrophobic nature of the spore surface and possibly also the spore interior. The water-sorption properties of naturally hydrated spores which had never been dehydrated before the experiment were studied. The rate of loss of water over P2O5 at 50 °C was measured in a closed chamber by remote weighing with a Cahn electrobalance. The hygroscopicity expressed as percentage of water bound by the sample at aw = 1, 25 °C was as follows.(I) Chemicals:albumin, 70.5; starch, 42.9.(II) Clostridium botulinum 33A, a heat-resistant strain: spores, 47.0; residue (spores heat killed at 121 °C for 30 min), 50.4; exudate (material released from heat-killed spores) 63.1; vegetative cells, 70.3.(III) C. botulinum, type E, strain Beluga, a heat-sensitive strain: spores 62.5; residue, 61.3; exudate, 77.3.It is postulated that molecular masking in the spore is responsible for low binding of water, electrical and chemical inertness, biological dormancy, and high heat resistance of bacterial spores.
Chikungunya virus in salivary glands of Aedes aegypti (L.): an electron microscope study
Authors: Janzen H. G. , Rhodes A. J. , Doane F. W.
Published: February 2010

Aedes aegypti were infected with chikungunya virus by being fed on a blood–virus suspension poured over a sugar cube. The virus infection in the salivary glands was then studied with the electron microscope. In the proximal portion of the lateral lobes, 250–310 Å virus precursor particles were seen in the nucleus, in the cytoplasm, and on the membranes of cytoplasmic vesicles. Enveloped 500–580 Å virus particles with a 250–310 Å core were seen within the vesicles, in intercellular spaces, and in large numbers in the apical cavity and periductal space. In the distal portions of the lateral and median lobes precursor particles were present in the nucleus and cytoplasm, but no cytoplasmic vesicles were seen. Numerous enveloped virus particles were seen in the apical cavity and periductal space, and in the median lobe within the duct lumen as well. No evidence of virus replication was seen in the intermediate portion of the median lobe.In the distal portions, virus particles were frequently associated with a concentration of the secretory material. No other microscopically visible pathological changes were seen in the infected salivary glands.
Detection of cross-reactions by immunofluorescence within the picornavirus group
Authors: Chaudhary R. K. , Westwood J. C. N.
Published: February 2010

A rapid and sensitive method has been developed to determine the degree of cross-reactions within the picornavirus group by the indirect method of fluorescent antibody staining in green monkey kidney cells. The viruses included in the study were poliovirus type 1, 2, and 3; echovirus type 3, 9, and 11; and coxsackievirus type A9 and B5. It has been found that the cross-reactions are in fact extensive amongst the viruses tested. The heterologous reactions were almost as strong as homologous reactions. The degree of group reactivity was unexpected and its implication and advantages are discussed.
CO2 control of fruiting in Schizophyllum commune: noninvolvement of sustained isocitrate lyase derepression
Authors: Cotter D. A. , LaClave A. J. , Wegener W. S. , Niederpruem D. J.
Published: February 2010

The activity of the enzyme, isocitrate lyase, was repressed in glucose cultures of Schizophyllum commune and derepressed in acetate-grown mycelium of this basidiomycetous fungus. The maximum acetate-derepressed level of this soluble enzyme was comparable in individual homokaryotic mycelium or in the dikaryon. Addition of CO2, NaHCO3, or CaCO3 did not significantly derepress isocitrate lyase activity in glucose-cultures. Neither normal dikaryotic fruiting nor its inhibition by carbon dioxide resulted in marked and sustained changes in isocitrate lyase. Thus, a fluctuation in isocitrate lyase activity does not appear to be the salient response of S. commune to increased CO2 tension.
Inhibition of the induced synthesis of protocatechuate oxygenase by o-nitrobenzoic acid
Authors: Montgomery Karen F. , Durham Norman N.
Published: February 2010

The synthesis of protocatechuate oxygenase (EC. 1.13.1.3), an inducible enzyme, by Pseudomonas fluorescens was inhibited by o-nitrobenzoic acid. The inhibitor did not alter the oxygenase activity of induced cells. Viable cell counts indicated that o-nitrobenzoic acid, in the concentrations used in these experiments, did not kill the cells. The inhibitor decreased the incorporation of L-tryptophan-14C and DL-glutamic-14C acid into the hot trichloroacetic acid insoluble fraction of the cell, but had no effect on the uptake of either radioactive amino acids or the inducer, protocatechuic acid. The synthesis of β-galactosidase by Escherichia coli was also inhibited by o-nitrobenzoic acid. The results establish that one site of o-nitrobenzoic acid inhibition is associated with protein synthesis in the cell.