bluuebunny/crossref_metadata_2025 huggingface dataset:
Ingestion and survival of Y. pseudotuberculosis in HeLa cells
Authors: Bovallius Åke , Nilsson Gustaf
Published: April 2010

HeLa cells were infected with Yersinia pseudotuberculosis for 0.5–3 h. Intracellular bacteria could then be demonstrated by three different techniques: viable count, fluorescent-antibody staining, and electron microscopy. Most of the bacteria seemed to be viable, since there was a good positive correlation (0.94) between viable and fluorescent bacteria. The bacterial uptake seemed to be mediated by a phagocytic-like procedure. The intracellular bacteria seemed to reside in vacuoles some of which increased in size as a function of time. The kinetics of infection was studied after addition of 107 or 109 bacteria per cell culture (2 × 106 cells). After a lag period of about 30 min there was a linear increase of intracellular bacteria, and this uptake proceeded for 1–2 h until most of the bacteria were ingested or an upper limit of ingested bacteria was reached. The upper limit was calculated to be a mean of 60 per infected cell in the cell culture. More than 90% of the cells could be infected and a reasonable number of the bacteria survive in the cells for at least 3 days, as demonstrated by the viable-count technique.The bacteria–cell system may be used to study, for example, the effect of antibiotics or antibodies on intracellular bacteria and pathogenicity of intracellular diseases.
SDS – polyacrylamide gel electrophoresis of lipopolysaccharides
Authors: Russell R. R. B. , Johnson K. G.
Published: April 2010

Lipopolysaccharides (LPS) prepared from four different species of Neisseria have been separated by SDS – polyacrylamide gel electrophoresis. Each LPS possessed a characteristic mobility on gels. Examination of the effect of acrylamide concentration on migration illustrated that the basis of the separation was molecular size, and not intrinsic charge.
Quantitative assessment of the bacterial rhizosphere flora of Pinus contorta var. latifolia
Authors: Dangerfield J. A. , Westlake D. W. S. , Cook F. D.
Published: April 2010

The bacterial flora associated with root systems of young and mature lodgepole pine was investigated by sampling forest-grown trees. Counts were performed and expressed on a surface-area basis to give a more realistic comparison of organism density or activity within the control soil, rhizosphere soil, and rhizoplane. On this basis, densities increased by an order of 104- to 106-fold from control soil to rhizoplane, with the degree of stimulation being inversely related to root radius.
Microcycle conidiation in Penicillium urticae: an ultrastructural investigation of spherical spore growth
Authors: Sekiguchi J. , Gaucher G. M. , Costerton J. W.
Published: April 2010

A cultivation system has been developed for Penicillium urticae (NRRL 2159A) which yields 'microcycle' conidiation in submerged culture. Spherical growth of spores was initiated by incubation at 37 °C in a growth-favoring medium. Transfer of these enlarged spores to a nitrogen-poor medium at 35 °C resulted in synchronous germination and limited outgrowth followed by roughly synchronous conidiation. An ultrastructural study of the spherical growth stage indicates a significant loss of cell envelope fine structure and a general increase in the number of cellular organelles. Loss of the complex pattern of rodlet s on the spore surface, and the trench-like invaginations of the plasma membrane were most prominent. From an ultrastructural point of view these large spores (about 6 μm in diameter) appeared to be perfectly normal.
Microcycle conidiation in Penicillium urticae: an ultrastructural investigation of conidial germination and outgrowth
Authors: Sekiguchi J. , Gaucher G. M. , Costerton J. W.
Published: April 2010

A cultivation system has been developed for Penicillium urticae (NRRL 2159A) which yields 'microcycle' conidiation in submerged culture. Spherical growth of conidia was initiated by incubation at 37 °C in a growth-favoring medium. Transfer of these enlarged conidia to a nitrogen-poor medium at 35 °C resulted in synchronous germination and limited outgrowth followed by roughly synchronous conidiogenesis. An ultrastructural study of the germination stage indicated nuclear migration into the emerging germ tube whose new cell wall was an extension of the parent conidium's innermost cell wall layer. Septal formation at the neck of the germ tube followed. The septal pore was filled with particulate material and the septal membranes possessed unusual linear elements in their median hydrophobic zones. The germ tube, which possessed a smooth-surfaced plasma membrane, continued to elongate with periodic septum formation. The parent conidium and later the proximal germ tube showed progressive vacuolation and the cytoplasm became largely occupied by electron-translucent material. In older cells the septal pore was blocked by Woronin bodies. Compared with normal conidial germination this 'microcycle' germination is far more synchronous and the resultant germling is morphologically simpler. In ultrastructural terms, however, germination appears to be identical with that obtained at 28 °C.
Antigenic and morphologic comparisons of Ibaraki and bluetongue viruses
Authors: Campbell C. H. , Breese jr. S. S. , McKercher P. D.
Published: April 2010

Bluetongue disease virus, type 10, and Ibaraki disease virus, which causes a bluetongue-like disease of cattle, were compared to determine whether they are the same or different viruses. They were similar in morphology, but neutralization tests, complement-fixation tests, and ferritin tagging indicated that they have antigenic differences. Therefore, they should be considered as different viruses. Two other viruses of this group, African horsesickness and equine encephalosis, were included.to show that Ibaraki and bluetongue had developmental morphological features that could be used to differentiate them from the two equine viruses.
Glycerol metabolism in Rhizobium
Authors: Arias A. , Martinez-Drets G.
Published: April 2010

Four strains of Rhizobium japonicum and one strain of R. trifolii were grown on glycerol and found to contain a soluble ATP-glycerol kinase and a particulate glycerophosphate dehydrogenase. Both enzymes are induced by glycerol. The presence of NAD+– or NADP+–glycerol dehydrogenase was not detected in any of the strains. No significant differences were found in the glycerol metabolic pathway between fast- and slow-growing rhizobia.
Production, purification and characterization of thermomycolase, the extracellular serine protease of the thermophilic fungus Malbranchea pulchella var. sulfurea
Authors: Ong Poh Seng , Gaucher G. Maurice
Published: April 2010

The thermophilic fungus Malbranchea pulchella produces a single extracellular, alkaline, serine protease when grown at 45 °C, on 2% casein as sole carbon source. The growth-associated production of protease in submerged cultures was inhibited by addition of glucose, amino acids, or yeast extract. A simple four-step purification which yields homogeneous protease in 78% yield is described. The protease has an isoelectric point of 6.0, a pH optimum of 8.5, and is completely inhibited by serine protease inhibitors. A specificity study with small synthetic ester substrates indicated that the protease preferentially hydrolyzed bonds situated on the carboxyl side of aromatic or apolar amino acid residues which are not β-branched, positively charged or of the D configuration. Peptidase substrates and others such as N-acetyl-L-tyrosine-ethyl ester were not hydrolyzed. The protease was stable over a broad range of pH (6.5–9.5 at 30 °C, 20 h), and was particularly thermostable (t1/2 = 110 min at 73 °C, pH 7.4) in the presence of Ca2+ (10 mM). Macromolecules and Ca2+ also provide protection against the significant autolysis which occurs at pure protease concentrations greater than 0.01 mg/ml, as well as against surface denaturation which is enhanced by the presence of a silicone antifoam agent. Hence the stability of protease in submerged cultures is rationalized.
An electron-microscopic study of Herpetomonas sp. (Leptomonas pessoai)
Authors: Souza Wanderley De , Rossi M. A. , Kitajima E. W. , Santos R. R. , Roitman I.
Published: April 2010

The fine structure of the promastigotes of Herpetomonas sp. (Leptomonas pessoai) kept in a defined medium at 28 °C is described. This protozoon reveals several features in common with other trypanosomatids. A membrane-bounded organelle measuring 0.2 to 0.8 μm in diameter, similar to that described as peroxisome in Crithidia fasciculata, was also observed. A large cavity, located between the nucleus and the kinetoplast and containing vesicles and small particulate material is discussed in this paper.
β-Glucanases in the yeast Cryptococcus albidus var. aerius. Production and separation of β-glucanases in asynchronous cultures
Authors: Notario V. , Villa T. G. , Benítez T. , Villanueva J. R.
Published: April 2010

β-Glucanases were detected in cell-free extracts of the yeast Cryptococcus albidus var. aerius when grown on glucose as the sole carbon source. The production of β-glucanases was followed in log-phase cells and stationary-phase cells; the maximal production of β-(1 → 3) and β-(1 → 6) glucanases takes place respectively in log-phase and stationary-phase cells. The results show that there are marked differences in the elution profiles on Sephadex G-50 of fractions containing β-glucanase from cells grown for 12, 24, 48, 72, and 96 h. The possibility either of replacement changes in fractions containing β-glucanase activity or of a different synthesis of each β-glucanase during the growth of the yeast is discussed. The results suggest that all fractions containing β-glucanases hydrolyze both β-(1 → ) and β-(1 → 6) linkages.Evidence in support of the conclusion that a low molecular form of β-glucanase has a molecular weight of 2100 ± 100 is also shown.
Temperature–pH effect upon germination of bacterial spores
Authors: Ishida Yuzaburo , Ishido Takashi , Kadota Hajime
Published: April 2010

Using several kinds of criteria for the germination of bacterial spores, germination–pH curves were drawn for Bacillus subtilis spores observed at different temperatures. The experiments revealed that optimum pH for spore germination was markedly changed by changing the incubation temperature; the optimum pH for germination was 7.4 at 37 °C and 5.4 at 10 °C. A possible mechanism involved in this phenomenon is discussed.
Temperature optima for bacteria and yeasts from cold-mountain habitats
Authors: Mosser Jerry L. , Herdrich Gary M. , Brock Thomas D.
Published: April 2010

Optimal temperatures for the growth of bacteria and yeasts isolated from several cold-mountain habitats were determined. The lowest optimal temperatures encountered were in the 10–15 °C range, even though most of the isolates were obtained from sites at or near 0 °C.
Etude de quelques facteurs intervenant dans la colonisation du tube digestif de la souris blanche par le Candida albicans
Authors: Auger Pierre , Joly Jeannine
Published: April 2010

This paper deals with the quantitative localization of Candida albicans in different parts of white mice gastrointestinal tract after oral inoculation of the yeast. Animals are previously treated with ampicillin, cortisone, or estradiol. Female pregnant and normal adult mice are also used.Our results show that the number of yeasts increases respectively in small intestine, stomach, caecum, and sigmoid. As compared with normal adult mice, C. albicans is more abundant in mice treated with ampicillin or cortisone whereas the yeast growth is lower in pregnant animals or in mice receiving estradiol. Moreover, male animals ordinarily show higher values than those found in female mice.
Phosphopantothenic acid—the major product of pantothenic acid accumulation and a significant growth stimulant in Lactobacillus plantarum
Authors: Germinario Ralph J. , Waller James R.
Published: April 2010

Non-proliferating cells of Lactobacillus plantarum accumulated about 1.3 μg of pantothenic acid (PA) per milligram dry cells when placed in a phosphate-buffered solution containing glucose, NaCl, and PA for 21 h. Under the conditions applied for PA uptake, pH 7.5 and 38 °C, the accumulated PA existed almost exclusively in a bound form. Free PA was observed only occasionally and then at questionably significant levels. All bound PA was released quantitatively by enzyme hydrolysis with alkaline (intestinal) phosphatase. Chromatographic analysis coupled with differential microbiological analysis of cell extracts using Saccharomyces cerevisiae, Lactobacillus helveticus, and L. plantarum identified the accumulated PA as phosphopantothenic acid (P-PA). Assay of P-PA loaded cell extracts (devoid of free PA) by L. plantarum before and after alkaline phosphatase hydrolysis showed that the growth of this primary assay organism was stimulated by 8.3%.
Dry-heat inactivation of Bacillus subtilis var. niger spores with special reference to spore density
Authors: Molin G. , Östlund K.
Published: April 2010

The dry-heat inactivation kinetics of Bacillus subtilis var. niger (ATCC 9372) spores has been studied in the temperature range of 120–190 °C. The spores were applied to glass plates of a standardized area (3.24 cm2).Spore preparations of five different spore densities were used (8.3 × 104, 7.4 × 105, 7.8 × 106, 6.3 × 107, and 6.6 × 108 spores per sample, respectively). The heat resistance of the spore was dependent on the number of spores per surface unit. Maximum resistance was observed when the concentration was 7.4 × 105 spores per sample. The D-values obtained at 160 °C from these samples were about twice as high as the D-values obtained from samples with a concentration of 6.3 × 107 or 6.6 × 108 spores per sample. The z value was found to be independent of spore density. Thus, for the two concentrations 7.4 × 105 and 6.3 × 107 spores per sample, the z-value was found to be 22 °C and constant over the temperature range investigated.
Selection of synchronous bacterial cultures by density sedimentation
Authors: Baldwin W. W. , Wegener W. S.
Published: April 2010

A procedure previously used to select synchronous cultures of Chlorella was found to produce similar results with the bacterium Lineola longa (Bacillus macroides). A midlog culture of L. longa was layered onto a 31–42% dialyzed Ficoll gradient and ceitrifuged at 51 000 3 g. The culture sedimented into a broad band in 30 min. Continued centrifugation failed to cause further migration. Cells taken from the top of the band and reinoculated into the broth in which they had previously grown, pH adjusted to 7.0, grew without a lag, doubled in optical density at the same rate as midlog cultures, and divided synchronously. Coulter counter sizing of these cells showed a doubling in volume just before division followed by a halving of volume after division. The major advantages of this method are the low osmolarity of Ficoll and the large volume of cells that can be separated.
Structure and composition of the cell wall of Choanephora cucurbitarum
Authors: Letourneau D. R. , Deven J. M. , Manocha M. S.
Published: April 2010

Mechanically isolated, cytoplasm-free cell walls of Choanephora cucurbitarum were analyzed qualitatively and quantitatively by use of microchemical methods, infrared spectrophotometry, and X-ray diffraction. Chemical analysis of cell wall revealed the presence of chitin (17%), chitosan (28.4%), neutral sugars (7.2%), uronic acid (2.4%), proteins (8.2%), and lipids (13.8%). The structure of hyphal wall, investigated by electron microscopy of shadowed replicas before and after alkali-acid hydrolysis, showed two distinct regions: microfibrillar and amorphous. The microfibrils, which were composed of mainly chitin, were organized into two distinct layers; an outer, thicker layer of randomly oriented microfibrils, and an inner, thin layer of parallel microfibrils. In its structure and chemical composition the cell wall of C. cucurbitarum resembles those of other zygomycetous fungi.
Effect of hydroxamic acids on growth and urease activity in Corynebacterium renale
Authors: Nervig Robert M. , Kadis Solomon
Published: April 2010

Studies were conducted on the effect of four different hydroxamic acids (HA), hydroxyurea, acetohydroxamic acid, p-fluorobenzoylhydroxamic acid and sorbylhydroxamic acid, on the growth and urease activity of Corynebacterium renale. The addition of each of these HA, at concentrations ranging from 10−3 to 10−5 M, to medium containing urea as the sole nitrogen source resulted in a lengthened lag period of growth the extent of which depended upon the concentration of each HA tested as well as the structure of the compound; that is, the size and (or) complexity of the side chain attached to the common terminal group of the molecule. However, the maximal growth levels achieved following conclusion of the exponential phase were not affected by the HA. Investigations on the effect of these HA on the urease activity of intact cells as well as cell-free extracts revealed that in each case the enzymatic activity was inhibited by each of the HA tested. The extent of inhibition with the intact cells was about one-half of that observed with cell-free extracts. Direct incubation of cell-free extracts as well as intact cells with each of the HA tested was required for maximal inhibition.
Superficial cell-wall layers on Spirillum "Ordal" and their in vitro reassembly
Authors: Beveridge T. J. , Murray R. G. E.
Published: April 2010

The cell envelope of Spirillum sp. strain "Ordal" (possibly a variety of S. anulus) demonstrated multiple superficial wall layers which were diverse in their macromolecular arrays. Negative staining and freeze-etching techniques revealed an outer hexagonally packed layer and an inner tetragonally packed layer. However, both thin sections and freeze-etched cleavages of the wall showed that each of these regular structures rested upon a backing layer, and that there was a delicate amorphous layer overlying the outer hexagonal array. Rotary integration, optical diffraction, and reconstruction of image were used to clarify measurements of each array and to verify the validity of a diagrammatic model of the outer hexagonal system. The integrity of these layers required suitable cations (Ca2+ appeared essential) and pH ([Formula: see text] dissociated most superficial layers). These observations aided in the development of a low-pH cationic-substitution technique, in which Na+ replaced essential Ca2+, for extraction of the layers from the cell surface. Dialysis to remove Na+ and restoration of Ca2+ initiated in vitro reassembly of the superficial layer components until regularly structured assembly products were formed.
Comparison of the biodegradability of crude and fuel oils
Authors: Walker J. D. , Petrakis L. , Colwell R. R.
Published: April 2010

Crude and fuel oils were compared for ability to support growth of a mixed population of estuarine bacteria. A total of four oils, two crude and two fuel oils, were examined. It was found that each of the oils supported a unique population of bacteria and yeasts, with respect to generic composition. Low-sulfur, high-saturate, South Louisiana crude oil was found to be highly susceptible to degradation. In contrast, the dense, high-sulfur, high-aromatic, Bunker C fuel oil was strongly refractory to microbial degradation.
Arrangement of morphological subunits in bacterial spinae
Authors: Easterbrook K. B. , Willison J. H. M. , Coombs R. W.
Published: April 2010

The filament, that is helically arranged to form the bacterial spina, is composed of morphological subunits (oligomers) about 5.6 nm in width and 11 nm in length. The oligomers are asymmetrical in that the inner surface is grooved. Image analysis of negative-stained spinae ribbons indicates that the oligomers are paired, possibly beaded structures, the arrangement of which is easily distorted during preparation. In intact spinae, the oligomer orientation may be normal to the filament axis, but in collapsed freeze-etched spinae, the oligomers are inclined at a constant angle of about 72° to the filament axis.
Prodiginine (prodigiosin-like) pigments from Streptomyces and other aerobic Actinomycetes
Authors: Gerber Nancy N. , Lechevalier M. P.
Published: April 2010

About 95 microorganisms, mainly streptomycetes, were examined for prodiginine pigments. The test methods, including some media for stimulating pigment production, are given. All nine strains which produced prodiginine pigments were characterized and the pigments identified. The results were used to propose structures for five prodigiosin-like pigments from actinomycetes reported in the literature between 1947 and 1964. Streptoverticillium sp. 26-1 furnished good yields of butylcycloheptylprodiginine (I), whose antimicrobial activity is given.
Un ARN extrait d'Agrobacterium tumefaciens, souches oncogènes et non oncogènes, élément indispensable à l'induction des tumeurs chez Datura stramonium
Authors: Goff L. Le , Cunha M. I. Aaron-Da , Beljanski M.
Published: April 2010

An RNA bound to the reverse transcriptase of Agrobacterium tumefaciens has been isolated and shown to be oncogenic for stem tissues of Datura stramonium grown under axenic conditions. The tumorous nature of the cellular change induced by the infectious RNA was demonstrated by serial grafts of tumors on Datura stems and by cultivation of tumorous tissue in vitro on a medium without supplemental auxins and cytokinins. Active cellular proliferation within tissues of Datura stems was a prerequisite for expression of the oncogenic potential of the RNA. Further, infectious RNA was isolated from avirulent and attenuated strains of Agrobacterium tumefaciens including attenuated derivatives of strain AC58 which have been "heat-cured" of the plasmid associated with virulence. It is proposed that the infectious RNA is an essential but not the sole component of the tumor-inducing mechanism of the crown-gall bacterium.
Inhibition of growth, iron, and sulfur oxidation in Thiobacillus ferrooxidans by simple organic compounds
Authors: Tuttle Jon H. , Dugan Patrick R.
Published: April 2010

Iron and sulfur oxidation by Thiobacillus ferrooxidans as well as growth on ferrous iron were inhibited by a variety of low molecular weight organic compounds. The influences of chemical structure of the organic inhibitors, pH, temperature, physical treatment of cells, and added inhibitory or stimulatory inorganic ions and iron oxidation suggest that a major factor contributing to the inhibitory effects on iron oxidation is the relative electronegativity of the organic molecule. The data also suggest that inhibitory organic compounds may (i) directly affect the iron-oxidizing enzyme system, (ii) react abiologically with ferrous iron outside the cell, (iii) interfere with the roles of phosphate and sulfate in iron oxidation, and (iv) nonselectively disrupt the cell envelope or membrane.
Nematophagous fungi: three new species of Myzocytium
Authors: Barron G. L.
Published: April 2010

Three species of Myzocytium parasitic on nematodes are described as new. In M. papillatum the zoospores encyst directly on the host cuticle before penetration. This species produces smooth, spherical oospores. In M. glutinosporum the biflagellate zoospores do not attack the host directly; after encystment they produce a spherical adhesive bud which allows the spores to adhere to the cuticle of passing nematodes. This species produces echinulate, spherical oospores. In M. anomalum the primary spores are aplanospores. After a dormant phase, and when suitably stimulated, these aplanospores change into biflagellate zoospores and the latter encyst on the host cuticle. No sexual state is known in this species. Persistence is by means of thick-walled, spherical chlamydospores.
Characterization of a temperature-sensitive mutant of Saccharomyces cerevisiae that undergoes uncontrolled protein synthesis
Authors: Gentile James M. , Nadakavukaren Mathew J. , Richardson Arlan
Published: April 2010

A mutant of Saccharomyces cerevisiae, DW137, was isolated after treatment of a wild-type strain with ICR-170. The mutant was respiration-deficient and showed abnormal cell division when grown at 30 °C. In addition, the mutant was temperature-sensitive and underwent lysis when grown at 37 °C. Random spore analysis, induced reversion profiles, and complementation analysis indicated that the abnormal phenotypes were under the control of a single recessive mutation caused by a base-pair substitution in a nuclear gene. Macromolecular analysis of the mutant at permissive and restrictive temperatures showed that at restrictive temperatures the mutant cannot synthesize DNA. Surprisingly, at restrictive temperatures, protein synthesis in the mutant continued at a rate greater than that observed at permissive temperatures. Cell death and lysis of the mutant could be prevented by treatment of cultures with cycloheximide, an inhibitor of protein synthesis. The data suggest that the abnormally high rate of protein synthesis and the inability to synthesize DNA are jointly responsible for death of the cells, and most probably play an integrating role in the incipient cell lysis.
The effect of light on acid-soluble polysaccharide accumulation in Sclerotium rolfsii Sacc.
Authors: Miller R. Michael , Liberta Anthony E.
Published: April 2010

A light-stimulated increase in β-1,3 glucan accumulation was observed for Sclerotium rolfsii Sacc. The acid-soluble polysaccharide accumulated in large quantities in 'white' light- and blue light-grown cultures. This polysaccharide also accumulated in both dark- and red light-grown cultures as well. However, the quantities were significantly lower when compared to the 'white' light- and blue light-grown cultures. A greater quantity of polysaccharide accumulated in red light-grown cultures than in dark-grown cultures.
Biochemical characterization of a cortexless mutant of a variant of Bacillus cereus
Authors: Pearce Susanne M.
Published: April 2010

Previous studies on this cortexless mutant of Bacillus cereus var. alesti indicated that the forespore membrane was the site of the biochemical lesion. This hypothesis is supported by the results presented here: fatty acid composition of sporulating cells of the mutant is altered, while in vegetative cells it is comparable to the parent; soluble precursors of peptidoglycan synthesis are accumulated in the mutant, at the time of cortex formation; homogenates of the mutant prepared at the time of cortex formation are unable to incorporate tritiated diaminopimelic acid into peptidoglycan, while homogenates of cells forming germ cell wall do so to an extent comparable to that of the parent; lipid-linked intermediates are formed by the mutant as in the parent. Apparently the mutant is unable either to transfer disaccharide penta-peptide units from the carrier lipid to the growing peptidoglycan acceptor, or to transport lipid-linked intermediates across the forespore membrane.
The fine structure of conidial development in the genus Torula. IV. T. thermophila Cooney & Emerson
Authors: Ellis D. H. , Griffiths D. A.
Published: April 2010

Torula thermophila produced typical chlamydospores either as intercalary chains within prostrate hyphae or as terminal swellings on short, lateral, hyphal branches. Mature chlamydospores were spherical, dark brown, smooth-surfaced structures with thick, single-layered cell walls (= secondary wall layer) usually differentiated into an outer electron-dense zone and an inner electron-transparent zone. Disarticulation and spore release occurred after the disintegration of the original hyphal wall.The thallospores of T. thermophila arise in a manner different from the blastospores produced by other species of Torula and are structurally more closely related to the spores produced by Humicola insolens. However until further work has been completed on spore development in the Torulu-Humicola complex of fungi the name T. thermophila is retained.
Antibody production in milk serum of goats experimentally infected with Neisseria gonorrhoeae
Authors: Pasieka A. E. , Ashton F. E. , Wallace R. , Ota F. , Ryan A. , Perusse C. , Diena B. B.
Published: April 2010

Instillation of the goat's mammary gland with Neisseria gonorrhoeae colony type Tl has elicited an antibody response in the goat milk serum (GMS). Purification, and characterization of the GMS by gel filtration, electrophoresis, immunodiffusion, analytical ultracentrifugation. And serological analyses demonstrated that the active immune component was mainly in the IgA and IgG fractions (F2 and F3) of GMS.
Un nouveau sérotype de Salmonella isolé au Canada: Salmonella montreal (431, 432: c: l,5)
Authors: Kasatiya S. S. , Petrow S. , Basu A. , Minor S. Le , Minor L. Le , Coueffic E. Le , Morrisset R.
Published: April 2010

A new serotype of Salmonella, Salmonella montreal (431, 432: c: 1,5) belonging to Kauffmann's sub-genus I was isolated from the faeces of a young male patient suffering from recurrent diarrhoea. [Journal translation]
The relationship between chemical structure of attractants and chemotaxis by a marine bacterium
Authors: Chet Ilan , Mitchell Ralph
Published: April 2010

The chemotactic responses of a marine pseudomonad to stereoisomers and analogues of amino acids and sugars were tested. The data reveal that the bacterium is equally attracted to D. L and DL forms of the amino acids. In contrast, chemical analogues of the amino acids and glucose yielded significantly lower chemotactic responses. The threshold of bacterial detection was 10−8 M for leucine and cysteine. However, the threshold molarity of most of the analogues was higher than those of the related amino acids and sugars.
Interaction between Pseudomonas pseudomallei and cultured rabbit peritoneal macrophages
Authors: Kishimoto Richard A. , Eveland Warren C.
Published: April 2010

The interaction between two strains of Pseudomonas pseudomallei of different virulence with normal and immune rabbit peritoneal macrophages was compared in vitro. Phagocytic activity of macrophages and bacterial survival within macrophages were dependent upon the virulence of the bacterial strain and the immune status of the macrophages. Virulent bacteria were more resistant than the less virulent strain to phagocytosis and destruction. Immune macrophages were more phagocytic and bactericidal than normal macrophages. Specific immune serum facilitated ingestion and destruction of bacteria by both normal and immune macrophages.
Transport of phenylalanine by conidia of Fusarium sulphureum
Authors: Barran Leslie R.
Published: April 2010

L-Phenylalanine was actively transported by conidia of Fusarium sulphureum Schlect (isolate 1). Uptake was optimal at pH 7, 30 °C; respiration-dependent; and was unaffected by relatively high internal concentrations of phenylalanine. The Km for transport was 1–3 × 10−5 M and the Vmax was 2.5–4 nmol/min per milligram dry weight. Phenylalanine is transported by a general transport system for basic and neutral amino acids. Sucrose repressed uptake of phenylalanine and this repression was largely negated by cycloheximide. Efflux of accumulated phenylalanine was influx-dependent; this transport system deteriorated slowly with aging of the conidial culture.
Effect of temperature and pH on the growth of Caryophanon latum colonies
Authors: Moran James W. , Witter Lloyd D.
Published: April 2010

The influence of temperature and pH on the growth rate of Caryophanon latum colonies was determined by measuring the rate of change in colony diameters. The colony growth rate had an optimum pH of 8.0, an optimum temperature of 35 °C, and a temperature characteristic of 11 500 cal.
Macrophage function and host resistance against infection with Toxoplasma gondii
Authors: Hof H. , Höhne K. , Seeliger H. P. R.
Published: April 2010

The role of macrophages on the course of an infection with Toxoplasma gondii has been examined. Stimulation of macrophage function by killed Bordetella pertussis cells did not show any beneficial effect as an increased susceptibility became apparent. The functional blockade of macrophages by dextran sulfate or carbon particles did not result in a higher susceptibility of mice to the lethal primary infection with T. gondii. Thus in vivo macrophages apparently do not play an essential role as effector cells as they do in infections with other obligate intracellular infective organisms such as Listeria monocytogenes.The spleen is apparently of crucial importance for resistance against T. gondii infection, since death occured earlier in splenectomized mice than in control animals.
Ecological distribution of Spirillum lipoferum Beijerinck
Authors: Dobereiner J. , Marriel I. E. , Nery M.
Published: April 2010

A survey in various countries revealed that the N2-fixing Spirillum lipoferum Beijerinck is a very common root and soil inhabitant in the tropics. More than half of the grass root and soil samples collected in tropical countries (four African countries and Brazil) contained abundant S. lipoferum populations, while less than 10% of the samples collected in temperate South Brazil, Kenya, and the U.S.A. contained the organism. There is a pronounced vegetation effect. Panicum maximum seems the most favorable among the forage grasses, while few positive samples were found under virgin tropical forest. Legume roots contained less S. lipoferum than adjacent soils. More than 80% of the samples from cereal roots (maize, sorghum, wheat, and rye) grown in fields fertilized with PK and Mo, in Rio de Janeiro State, were positive. Maize and sorghum grown under similar conditions in Wisconsin contained less than 10% of positive samples, but when maize fields were inoculated 90% of the root samples contained S. lipoferum. Alluvial soils were more favorable than eroded hill soils. Occurrence in soil was strongly pH-dependent with a pH around 7, being optimal (correlation coefficient r = 0.90). Sporadic occurrence was observed even in soils with pH 4.8. Surface-sterilized P. maximum roots collected from soils with pH ranging from 4.8 to 7.2 contained high S. lipoferum numbers which did not correlate with soil pH (r = 0.41). Amendment with malate of acid soils was not very effective in increasing nitrogenase (N2-ase) activity, but in two soils with pH above 6.4, high N2-ase activity was obtained after 16 to 48 h of incubation. In two soils from a temperate climate region, inoculation with S. lipoferum increased N2-ase activity produced through malate amendment.
The effects of glucosamine derivatives on the growth of cultivable Treponema
Authors: Thomas John J. , Thomas Betty J. , Jones Ronald H. , Folger Edward C.
Published: April 2010

The effects of glucosamine and its derivatives on the growth of Treponema phagedenis biotypes reiter and kazan 5 were studied to determine if these agents could act as growth stimulants for organisms of the genus Treponema. Growth studies on the cultivable treponemes were conducted in culture tubes containing glucosamine, glucosamine derivatives, and (or) glucose and galactose in serum-based media. Glucosamine and N-phenylacetylglucosamine were definitely inhibitory to growth at the concentrations studied. N-acetylglucosamine (NAG) produced mixed effects.
Thermothrix thioparus gen. et sp. nov. a facultatively anaerobic facultative chemolithotroph living at neutral pH and high temperature
Authors: Caldwell Douglas E. , Caldwell Sarah J. , Laycock J. Paul
Published: April 2010

Thermothrix thioparus gen. et sp. nov. occurs naturally in a New Mexico hot spring at a temperature of 74 °C, a pH of 7.0, and a HS− concentration of 1 mg/litre. The organism is gram-negative, non-motile, 0.5–1.0 × 3–20 μm, and forms cell chains up to 1 cm in length. The resulting filaments do not possess a sheath. Sulfur is deposited extracellularly. The organism was isolated using an autotrophic medium with HS− as the energy source and NO3− as the terminal electron acceptor. Anaerobically either NO2− or NO3− is required, NO2− is formed from NO3−, and no observable gas is evolved. Oxygen can also be used as the terminal electron acceptor, but growth is poor because of the decreased solubility of O2 at temperatures required for growth. Alternate energy sources used aerobically and anaerobically include hexose, HS− SO3−, and S2O3=. The temperature optimum is 70–73 °C and growth occurs from 62 to 77 °C. The organism's thermal and physiological characteristics are compared to those of Bacillus stearothermophilus, Methanobacterium thermoautotrophicum, Sulfolobus acidocalderius, Thermus aquaticus, Thermits flavus, as well as Thiobacillus denitrificans, the latter being the only other facultatively anaerobic chemolithotroph which has been isolated and described.
Functional and structural differences between photosynthetic and heterotrophic Rhodospirillum rubrum ribosomes and S-100 fractions
Authors: Chow C. T.
Published: April 2010

Cell-free, protein-synthesizing activity has been tested by using various combinations of the S-100 and ribosome fractions prepared from photosynthetic and heterotrophic Rhodospirillum rubrum. The photosynthetic ribosomes are highly active when combined with either the photosynthetic or the heterotrophic S-100 fractions, whereas the heterotrophic ribosomes are active only when combined with the photosynthetic S-100 fraction. Addition of a photosynthetic pigment-containing fraction to the homologous heterotrophic system is, however, able to stimulate its activity. An inhibitor and an activator involved in cell-free protein synthesis have been isolated from the stationary heterotrophic cells. The inhibitor is a very small, dialyzable compound which inhibits not only the R. rubrum but also the E. coli protein-synthesizing activity in vitro, whereas the activator is a non-dialyzable, small RNA molecule capable of stimulating only the R. rubrum activity. Differences exist between the photosynthetic and the heterotrophic systems in their response to various chemical compounds and to light as well as in their structure.
Leakage of periplasmic enzymes from lipopolysaccharide-defective mutants of Salmonella typhimurium
Authors: Chatterjee Arun K. , Ross Helen , Sanderson Kenneth E.
Published: April 2010

Mutants of Salmonella typhimurium with defects in the heptose region of the lipopolysaccharide (LPS) molecule (heptose-deficient, chemotype Re) leak periplasmic enzymes (acid phosphatase (EC 3.1.3.2), cyclic phosphodiesterase, ribonuclease I (EC 3.1.4.22), and phosphoglucose isomerase (EC 5.3.1.9) (PGI is at least partially periplasmic in E. coli and S. typhimurium; see below)) and do not leak an internal enzyme (glucose-6-phosphate dehydrogenase) into the growth medium. The extent of this leakage is markedly increased at higher temperature (42 °C). Leakage of periplasmic enzymes from the strains lacking units distal to heptose I in the LPS molecule (chemotype Rd2) occurs only at 42 °C, and not at 30 or 37 °C. The extent of leakage of these enzymes from smooth strain and mutants of other LPS chemotypes (Rc, Rd1) is not significant, and is not influenced by growth temperatures. The kinetics of leakage of periplasmic enzymes after shift to 42 °C in nutrient broth reveal an accelerated release into the medium from heptose-deficient strains of cyclic phosphodiesterase and ribonuclease I after 30 min at 42 °C, and phosphoglucose isomerase after 60 min at 42 °C; at 30 °C the rate of release of cyclic phosphodiesterase and ribonuclease I is relatively slower. After 60 min at 42 °C in nutrient broth, growth of these strains has either slowed down or stopped. In L-broth, which permits the growth of the heptose-deficient strain (SA1377) at 42 °C, leakage of cyclic phosphodiesterase and phosphoglucose isomerase occurs, whereas there is no detectable leakage of these enzymes from the isogenic smooth strain (SA 1355). Thus, leakage of the periplasmic enzymes from the heptose-deficient strain occurs with or without growth. Mg2+ (0.75 mM), sodium chloride (50 mM), and sucrose (100 mM) in nutrient broth at 42 °C prevent the leakage of these enzymes. The shedding of LPS from the heptose-deficient as well as the smooth strains is enhanced by high temperature (42 °C), whereas considerable leakage of protein occurs only in the heptose-deficient strain at 42 °C and not in the smooth strain. The smooth and heptose-deficient strains are equally sensitive to osmotic shock although a significant proportion of acid phosphatase and cyclic phosphodiesterase activities from the heptose-deficient cells grown at 42 °C comes off in the Tris-NaCl wash step suggesting a rather loose attachment of these enzymes onto the cell surface.
Suitability of membrane-filter techniques to study the ultrastructure of Fusarium solani in soil
Authors: Eck W. H. Van
Published: April 2010

The suitability of two types of membrane filters for scanning and transmission electron-microscopical examination of chlamydospores formed from macroconidia of Fusarium solani from soil was tested. An improved method to incubate propagules in soil and to collect them free from soil particles for electron-microscopical observations is described. Best results were obtained if macroconidia were incubated in soil between two Nuclepore membrane filters. Both chlamydospore morphology and lysis, however, were affected to some extent in comparison with that on single membranes. This is probably due to a selective effect on the microflora colonizing the chlamydospores.
Ultrastructure of forming and dormant chlamydospores of Fusarium solani in soil
Authors: Eck W. H. Van
Published: April 2010

Chlamydospores of Fusarium solani f. sp. cucurbitae, F. solani f. sp. phaseoli and F. solani f. sp. pisi formed in soil were recovered at intervals and examined by electron microscopy. Cell wall material outside the newly formed chlamydospore cell wall gradually disintegrated. Protoplasts of chlamydospore cells lyse without prior penetration of the cell wall by microorganisms. The mechanisms of lysis of chlamydospores of F. solani in soil are discussed.
Dégradation des hydrocarbures en présence d'autres substances organiques par des bactéries isolées de l'eau de mer
Authors: Petit J. Le , Tagger S.
Published: April 2010

Three bacterial strains, isolated on gas–oil from seawater, have a variously changed growth on hexadecane with supply of two organic substances. Acetate reduces growth of all tested strains and particularly the hexadecane degradation by Acinetobacter sp. On the contrary, trypticase–phytone promotes the degradation by the three strains.
Accelerated detection of lymphocytic choriomeningitis virus in diagnostic specimens
Authors: Lewis Vester J. , Thacker W. Lanier , Mitchell Shannon H.
Published: April 2010

Lymphocytic choriomeningitis virus could be demonstrated earlier in mice inoculated with clinical specimens if the mice were sacrificed before they appeared sick for examination by the fluorescent antibody technique. In the procedure, the optimal route for inoculation was intracerebral and the best organ tested for staining was the brain.
A miniaturized counting technique for anaerobic bacteria
Authors: Sharpe A. N. , Pettipher G. L. , Lloyd G. R.
Published: April 2010

A miniaturized counting technique gave results as good as the pour-plate and Most Probable Number (MPN) techniques for enumeration of Clostridia spp. and anaerobic isolates from the gut. Highest counts were obtained when ascorbic acid (1%) and dithiothreitol (0.015%) were added to the reinforced clostridial medium used for counting. This minimized the effect of exposure to air before incubation. The miniature technique allowed up to 40 samples to be plated and incubated in one McIntosh-Filde's-type anaerobic jar, compared with 3 or 4 by the normal pour plate.
Caractéristiques de l'accroissement de la résistance de la souris contre Pseudomonas aeruginosa provoqué par Staphylococcus aureus
Authors: Mathieu L. G. , deRepentigny J. , Gadbois T.
Published: April 2010

Mice were protected against a lethal dose of Pseudomonas aeruginosa by a previous sublethal infection with Staphylococcus aureus. Under similar conditions, Staphylococcus epidermidis afforded only slight protection.The following characteristics of this increased resistance that we have observed are (1) survival of mice, and decrease of the number of viable units of P. aeruginosa in the peritoneal cavity of the same mice infected with S. aureus coagulase-positive strains, either from our laboratory collection or from hospital cases, when the time interval between the injection with staphylococci and that of P. aeruginosa was between 4 and 96 h; (2) absence of a net inhibitory effect in vitro on P. aeruginosa with serum from mice infected with a sublethal dose of coagulase-positive S. aureus; (3) changes in the appearance of peritoneal exudate cells after infection with a sublethal dose of S. aureus; P. aeruginosa injected afterwards in the peritoneal cavity of mice was eliminated; when P. aeruginosa was injected alone, "activated macrophages" were not observed and bacterial cells were present in large numbers in the exudate. The immunostimulation induced by a previous sublethal injection of S. aureus coagulase-positive strains seemed to be inhibited by the immunosuppressive drug cyclophosphamide, since mice were no longer protected against a lethal dose of P. aeruginosa. Cell immunity may intervene in such infections with opportunistic species and check the invasiveness of a gram-negative bacterium superinfecting a host already exposed to coagulase-positive S. aureus.
Survival value of chemotaxis in mixed cultures
Authors: Pilgram Wendy K. , Williams Fred D.
Published: April 2010

A motile, chemotactic strain of Proteus mirabilis outgrew a motile, non-chemotactic mutant in a semisolid, amino acid medium, although the two strains grew equally well in broth.
Baculovirus-like particles in the reproductive tracts of female parasitoid wasps II: the genus Apanteles
Authors: Stoltz Donald B. , Vinson S. Bradleigh
Published: April 2010

Virus-like particles have been found in the female reproductive tracts of all Apanteles spp. thus far examined. Particles generally consist of putative baculovirus-like nucleocapsids which are enveloped singly or as groups within nuclei of calyx epithelial cells. Enveloped particles are injected into host caterpillars during oviposition. Subsequently, particle nucleocapsids appear in the cytoplasm of many host cells, and appear to be uncoated at nuclear pores.
Agglutinating immunoglobulins to encapsulated Streptococcus bovis in bovine serum and saliva and a possible relation to feedlot bloat
Authors: Horacek G. L. , Fina L. R. , Tillinghast H. S. , Gettings R. L. , Bartley E. E.
Published: April 2010

All bovine sera tested contained agglutinating immunoglobulins against encapsulated Streptococcus bovis. The immunoglobulins also were shown in predominantly parotid saliva. Cells grown in broth with added carbohydrate (sucrose) produced extracellular dextran (capsule) and were agglutinated by sera and saliva, but S. bovis cells grown in absence of carbohydrate were not agglutinated. The reacting material was established by adsorption with mono-specific anti-bovine gamma globulin to be an immunoglobulin. Sephadex adsorption studies showed the immunoglobulin specific to extracellular dextran. Sephadex adsorption also provided a way to isolate these immunoglobulins. Purified capsular dextran demonstrated a precipitin reaction with serum and saliva preparations. Because S. bovis capsule has been implicated in feedlot bloat, it is possible that antibodies reaching the rumen in bovine saliva may affect bloat.
Polyene antibiotic affinities for the sterols of resistant and sensitive strains of Neurospora crassa
Authors: Johnson D. , Subden R.
Published: April 2010

Ergosterol, the principle sterol of many wild-type Neurospora and other Ascomycetes, had a greater affinity for polyene antibiotics than did lichesterol or eburicol, the sterols of some resistant mutant strains. The affinity was demonstrated by comparing the sterols extracted from sensitive and resistant strains of Neurospora crassa and Candida albicans for protection against polyene inhibition of sensitive N. crassa and for their ability to alter specific polyene absorption maxima.