bluuebunny/crossref_metadata_2025 huggingface dataset:
Studies on diphosphopyridine nucleotidase and platelet damaging factor in an extracellular product of Listeria monocytogenes
Authors: Siddique I. H. , Ying L. C. , Chung R. A.
Published: February 2010

Hemolysin preparations from a virulent strain of Listeria monocytogenes were chromatographed on Sephadex G-100 and Sephadex DEAE A-50 columns. Three types of activities were identified: DPNase activity, hemolytic activity, and platelet-damaging activity. The separation of the peak with DPN-destroying activity from the peaks with hemolytic and platelet-damaging activities provided evidence that the factor in the solutions responsible for the destruction of DPN was distinct from that causing hemolysis and platelet-damage. The DPNase factor was found to be non-dialyzable, to be heat labile, and to have optimal activity in the pH range of 6.8–7.4.
Ergotamine production and metabolism of Claviceps purpurea strain 275 FI in stirred fermenters
Authors: Arcamone F. , Cassinelli G. , Ferni G. , Penco S. , Pennella P. , Pol C.
Published: February 2010

Strain 275 FI of Claviceps purpurea produces up to 1000 μg/ml of peptide alkaloids, mainly ergotamine, when grown in stirred and aerated fermenters on a sucrose – ammonium citrate medium for 9 to 10 days. Distinct phases of growth, related to the changing nutritional status and metabolic activity of the microorganism, can be defined. The first phase shows exponential growth, high [Formula: see text] and mycelial RNA values, and a rapid uptake of inorganic phosphate from the medium. The second phase shows linear growth and lasts till the time of ammonium nitrogen exhaustion; active alkaloid formation takes place during this phase, but continues with slower rate in the third phase.The highest yields of peptide alkaloids are obtained under conditions favoring "shunt" product formation, such as high carbohydrate and low phosphate concentrations in the medium. The ammonium citrate level, however, greatly influences the production pattern. Sucrose is converted by a β-D-fructo-furanosidase early during the first phase of growth to free glucose and a mixture of oligosaccharides which have been chemically characterized. This conversion is considered to be primarily responsible for prolonging the production phase so that high yields of the lysergic acid derivatives are attained.
Diacetyl reductase of Lactobacillus casei
Authors: Branen A. L. , Keenan T. W.
Published: February 2010

Diacetyl reductase (diacetyl:reduced nicotinamide adenine dinucleotide (NADH) oxidoreductase, EC. 1.1.1.5) has been isolated from Lactobacillus casei. Cell sonication, ammonium sulfate fractionation, Sephadex gel filtration, DEAE-cellulose chromatography, and alumina gel adsorption were used to obtain the partially purified enzyme. Both NADH oxidase and diacetyl reductase activity were associated with the same fraction at all stages in purification. Growth in media containing added pyruvate resulted in a 10-fold increase in the NADH oxidase activity and a 3-fold increase in the diacetyl reductase activity of crude cell extracts on a protein basis. Purified preparations showed maximal reductase and oxidase activities at pH 4.5 and 5.0, respectively. Lineweaver–Burke plots yielded intersecting lines when NADH and diacetyl concentrations were varied, suggesting a flavin-linked reaction. The absorption spectrum of the purified preparation was characteristic of that of a flavoprotein. The product of the reduction of diacetyl was identified as acetoin. Acetoin and methylene blue were inactive as acceptors.
A comparative study of some properties of the ØX174 type bacteriophages
Authors: Bradley D. E.
Published: February 2010

Members of the ØX174 group of coliphages are all morphologically identical. The host range patterns of the principal isolates on strains of Escherichia coli are shown to form three distinct groups. These are found to coincide with three serological groups. Some basic properties of the isolate St-1, which is the only one able to grow on male strains of E. coli, are described. Sections of phage-infected cells were examined in the electron microscope, and the structural changes produced by ØX174 and St-1 were found to be similar. The commonest mechanism of lysis consists of the formation of a small bulge at the midpoint of a dividing cell; this bursts and releases the cell contents.
Proflavine binding and release by sensitive and resistant Bacillus subtilis
Authors: Barabas Gy. , Mehta B. M. , Kushner D. J.
Published: February 2010

Proflavine binding of a sensitive strain of Bacillus subtilis and of a resistant strain derived from it was compared. Proflavine was bound very rapidly and more was bound at 0 °C than at 37 °C. Boiling increased the proflavine-binding capacity at 37 °C of sensitive but not of resistant cells. The binding capacity of sensitive and resistant cells suspended in buffer was the same; this was also true in various growth media. If cells were able to grow in the presence of proflavine their proflavine content decreased.Bound proflavine was released when cells were treated with growth media or with the salts of growth media. Sodium salts of organic acids also caused a release. This effect seemed due to their Na+ content, and was somewhat higher for resistant than for sensitive cells. The mechanism of proflavine resistance in B. subtilis is probably different from that of Escherichia coli, which is thought to depend on an energy-driven release of bound proflavine.
Intracellular development of a bacteriophage of Clostridium perfringens
Authors: Mahony D. E. , Easterbrook K. B.
Published: February 2010

A new bacteriophage of Clostridium perfringens was isolated which could cause complete lysis of its indicator strain in fluid culture. The adsorption characteristics and one-step growth experiments revealed that the phage rapidly adsorbed to the indicator strain and had a latent period of 45 min. Electron microscopy was performed on both thin sections and partially lysed preparations of infected bacteria at intervals throughout the growth cycle of the phage. This phage, named CPT4, has a head diameter of 64 nm and a striated tail 170 × 10 nm. In addition to these complete phages a number of "petit" phage forms was apparent in lysates. These forms were 55 nm in diameter, possessed no tail, and probably contained no nucleic acid.Morphogenic studies revealed that head forms appeared 30 min postinfection and that tails were present by 35 min. Assembly of mature phage particles seemed complete 40 min postinfection.
Glucose requirements of L cells infected with Chlamydia psittaci
Authors: Gill Shawn D'Arcy , Stewart Robert B.
Published: February 2010

Strain 929 mouse fibroblast L cells were found to consume about twice the normal amount of glucose when infected by the 6BC strain of the psittacosis agent. This was accompanied by an increase in lactic acid production. In addition, the yield of psittacosis organisms was related to the availability of glucose in the tissue culture medium when other constituents were held constant. Under conditions of limiting glucose, the addition of NAD or NADP improved the yield of psittacosis organisms. These results were discussed in relation to the energy parasite concept of chlamydial parasitism.
Typing of Rhizobium by phages
Authors: Staniewski Ryszard
Published: February 2010

Two hundred and thirty strains of Rhizobium trifolii, Rhizobium leguminosarum for pea, vetch, horse bean, and Lathyrus spp., Rhizobium phaseoli and Rhizobium meliloti were subjected to phage typing. On the basis of their sensitivity to phages these strains were divided into three groups: I, II, and III.In group I, consisting of R. trifolii, R. leguminosarum for pea, vetch, and horse bean, and R. phaseoli, 18 phage types were established. Group II included some strains of R. trifolii and R. leguminosarum for pea and vetch. Among them three phage types were distinguished. Group III included R. meliloti strains and one strain of Rhizobium lupini for lupine. In that group 10 phage types were found.
Studies on the cell wall of Spirillum serpens. 1. Isolation and partial purification of the outermost cell wall layer
Authors: Buckmire Francis L. A. , Murray Robert G. E.
Published: February 2010

The presence of the hexagonal array of macromolecules on the outer surface of the cell wall of Spirillum serpens VHA required the addition of calcium to an otherwise effective growth medium (vitamin-free casein hydrolysate); slightly improved growth resulted from addition of a complex salts mixture. A means of isolating this layer for chemical and physical study was sought and controlled by electron microscopy of freeze-etched, negatively stained, and sectioned preparations. The structure was destroyed, extracted, or removed by extremes of pH (<4.5, >9), 1 M guanidine hydrochloride (pH 7), 2 M urea, and dimethyl sulfoxide, with varying damage to the cell. Heat (60° for 1 h) removed much of the outer layer from the intact cell as an array of units disposed on a delicate backing layer, leaving the basic Gram-negative triplet wall components. These fragments remained stable through washing and repeated heating in the presence of 0.001 M calcium chloride. Guanidine hydrochloride (1.5 M) dissolved the units from the tubes and vesicles formed by the backing layer. Dialysis against water removed salts and guanidine, caused the precipitation of residual contaminants, and provided a supernatant which, when lyophilized, provided a product containing 98% protein.
An agar plate method for screening and enumerating pectinolytic microorganisms
Authors: Jayasankar N. P. , Graham P. H.
Published: February 2010

A simple agar-plate method for the rapid enumeration and isolation of pectinolytic microorganisms is described.
Keratinophilic activity in species of Corynebacterium
Authors: McBride Mollie E. , Freeman Robert G. , Knox John M.
Published: February 2010

Invasion of the hair cuticle in vitro has been described for three species of Corynebacterium isolated from cases of trichomycosis axillaris, an infection of the hair.
Ultrastructure of a marine psychrophilic Vibrio
Authors: Kennedy S. F. , Colwell R. R. , Chapman G. B.
Published: February 2010

The structure of Vibrio marinus strain PS-207 was studied by both phase and electron microscopy. It was found to possess a trilaminar plasma membrane and cell wall. Membrane-bounded subunits containing DNA-like material were found dispersed throughout the cytoplasm. Giant round forms or "macrospheres" were observed in all growth stages. The size, shape, and construction of the "macrospheres" showed some variation, but could not be related to culture age. Studies of cell division in V. marinus strain PS-207 indicate the primary mechanism to be a synthesis and centripetal deposition of plasma membrane with a concomitant or subsequent synthesis and centripetal deposition of cross wall material.
Respiration of L cells infected with Chlamydia psittaci
Authors: Gill Shawn D'arcy , Stewart Robert B.
Published: February 2010

Strain 929 mouse fibroblast L cells demonstrated an increased rate of endogenous and exogenous respiration when infected by the 6BC strain of the psittacosis organism. The respiratory quotient (R.Q.) values for infected cultures were about 1.0. Studies involving the use of 2,4-DNPand reduced phosphate suggested that the accelerated respiration was a result of increased oxidative phosphorylation. Infection was accompanied by a decline in host cell ATP levels with a concomitant increase in the ADP levels. A reduction in tissue culture medium phosphate resulted in a reduced yield of psittacosis organisms from infected cells and lower cellular levels of ATP. These results are discussed in relation to an energy parasite hypothesis.
Radiation survival of bacterial spores in neutral and acid ice
Authors: Grecz Nicholas , Upadhyay J.
Published: February 2010

Spores of C. botulinum 33A were irradiated at pH 2, 3, 4, 5, 6, and 7 to 0.6, 0.7, and 0.9 Mrad cobalt-60. Temperatures were controlled at −196 °C to 0 °C in distinct intervals. The survival data presented a complex wave-like pattern which appeared to be influenced by pH, temperature, and dose of radiation. Three typical survival patterns could be recognized. Pattern A (at −190 °C) showed peaks of high survival at pH 4 and 7 and low survival at pH 2 and 6. Pattern B (at −50, −40, and −30 °C) showed peaks of high survival at pH 3 and 6 and low survival at pH 2, 4–5, and 7.0. Pattern C (at 0 °C) was similar to pattern A but had generally higher peaks and deeper troughs. Between the temperatures showing typical A, B, and C patterns, the survival profiles indicated various degrees of transition from A to B or from B to C.The effect of pH appears to be related to its influence on yield of radicals in water such as, for example, ∙OH, which may result in highly lethal conditions within the region of low spore survival, and extinction of ∙OH by reaction with H∙ at the peaks of spore survival.
Yeasts isolated from the South Saskatchewan, a polluted river
Authors: Spencer J. F. T. , Gorin P. A. J. , Gardner N. R.
Published: February 2010

Minimum numbers of yeasts isolated from the Saskatchewan River in the summers of 1964 and 1965 ranged from 400 to 500 cells/liter upstream from the city of Saskatoon, to 4600 cells/liter immediately downstream. In the summer of 1968, a period of extremely low water, the counts were 150 cells/liter upstream from the city and 30 000 cells/liter downstream.Proton magnetic resonance spectra of the mannose-containing polysaccharides from representative cultures of the different species isolated were used as an aid in classification. Most of the species were asporogenous, and included representatives of the genera Candida, Trichosporon, Rhodotorula, Torulopsis, and Cryptococcus. Some species of Pichia, Saccharomyces, and Debaryomyces were isolated. The yeasts were mostly introduced into the river with the effluent from the Saskatoon sewage system.
Aflatoxin B1 effect on enzyme biosynthesis in Bacillus cereus and Bacillus licheniformis
Authors: Lillehoj Eivind B. , Ciegler Alex
Published: February 2010

The effect of aflatoxin B1 on induced and constitutive enzyme synthesis was examined in strains of Bacillus cereus (NRRL B-569, NRRL B-3537) and Bacillus licheniformis (NRRL B-3560, NRRL B-3540). Although B1 partially blocked penicillinase elaboration in B. cereus after incubation with the toxin, the level of B1-mediated reduction in total protein synthesis was similar to the diminished production of penicillinase. Comparative studies on the effects of aflatoxin B1 and actinomycin D on enzyme synthesis and growth in B. licheniformis demonstrated that actinomycin D exerted a differential inhibitory effect on induction of penicillinase and α-glucosidase, whereas levels of reduction of enzyme production initiated by aflatoxin resembled toxin-mediated growth inhibition. Thus, the mode of action of aflatoxin B1 is not exclusively analogous to that of actinomycin D in B. licheniformis. However, induced-penicillinase production in B. licheniformis was enhanced by relatively low levels of both actinomycin D and aflatoxin B1.
In vitro uptake of tritium from uridine-5-H3 into RNA (and DNA) in normal and murine leukemia virus infected mouse embryo tissue
Authors: Albach Richard A. , Gerber Mariette J. , Brown Eric R.
Published: February 2010

The multiplication and release into the medium of a murine leukemic virus (GC) occurs in mouse embryo tissue cultures. Autoradiographic analysis of such infected and uninfected cultures after 24-h labeling periods with uridine-5-H3 demonstrated extensive nuclear and cytoplasmic activity. Such activity was always more extensive in infected cultures, indicating that they were more metabolically active than uninfected cultures. The cytoplasmic activity was apparently in single-stranded RNA, since it was completely removed with pancreatic RNase. A portion of the nuclear label which was RNase-resistant was in DNA, since RNase followed by DNase, or the reverse, removed all label.Autoradiographic analysis of cultures given pulse labels of uridine-5-H3 from 5 to 60 min revealed only nuclear label, always more extensive in infected cultures. This indicates that the synthesis of "rapidly labeled" RNA is enhanced by viral infection; this occurs even within 2 h after infection. Nuclear activity observed after 5- and 10-min pulses was removed by buffers containing RNase or DNase. Possibly this label was in diffusible low molecular weight species of RNA. After 30-min pulses, activity was exclusively associated with pancreatic RNase-sensitive single-stranded RNA. After 60-min labeling, tritium from uridine-5-H3 was taken up into nuclear DNA in addition to RNA.
Chemical composition of lipopolysaccharide from an avian strain of Escherichia coli O18
Authors: Lopes J. , Inniss W. E.
Published: February 2010

Lipopolysaccharide (LPS) was isolated from an avian strain of Escherichia coli O18 by extraction of the cells with NaCl followed by treatment with phenol–water, methanol precipitation, and gel permeation chromatography. The LPS consisted of carbohydrate, lipid, and a small amount of protein and phosphate. Further analysis showed the presence of glucose, galactose, rhamnose, glucosamine, N-acetylglucosamine, heptose, 2-keto-3-deoxyoctonate (KDO), and ethanolamine. The composition of the LPS is qualitatively similar to that found for LPS obtained from various other bacteria.
Heterotrophic nutrition of the marine pennate diatom, Cylindrotheca fusiformis
Authors: Lewin Joyce , Hellebust Johan A.
Published: February 2010

Cylindrotheca fusiformis Reimann & Lewin, a marine littoral pennate diatom, can grow in the dark in media containing an organic substrate. Lactate, succinate, fumarate, malate, Tryptone, Casamino Acids, or Yeast Extract can serve as substrate. Glucose apparently cannot be used for heterotrophic growth. Cells taken from the light and used as inoculum for dark cultures began to multiply after a lag period; its length depends on the substrate concentration.Experiments with radioactively labeled organic compounds confirmed the growth experiments. C. fusiformis did not take up significant amounts of 14C-labeled alanine, glutamic acid, aspartic acid, acetate, or glucose, even after several days of preincubation in the dark with high concentrations of these compounds. Cells kept in the dark in the absence of organic compounds developed a capacity to take up lactate, but not succinate. Cells grown in the dark in the presence of lactate were able subsequently to take up radioactively labeled succinate as well as lactate.The generation time under optimum conditions in the dark was around 30 h, longer than for cells growing autotrophically in the light (generation time 12.5 h at 2000 lux). The pigment composition of dark-grown cells was similar to that of light-grown cultures, except that diadinoxanthin was not detectable in the dark-grown cells. Chromatophore structure in dark-grown cells was normal. Cells brought into the light after being cultured in the dark for 3 weeks evolved oxygen immediately upon illumination. C. fusiformis did not multiply under anaerobic conditions in the dark but could survive under these conditions for at least 2 months.
Cometabolism: a technique for the accumulation of biochemical products
Authors: Horvath R. S. , Alexander M.
Published: February 2010

Cometabolism was used as a technique to accumulate biochemical products in high yield. As a result of cometabolism, cells of three bacterial species converted 98% of m-chlorobenzoate, 95% of 2,3,6-trichlorobenzoate, and 93% of the 3,5-dichlorocatechol provided to 4-chlorocatechol, 3,5-dichlorocatechol, and 2-hydroxy-3,5-dichloromuconic semialdehyde, respectively.
Interaction between hyphae of Verticillium dahliae Kleb. during microsclerotial development
Authors: Griffiths D. A. , Campbell W.
Published: February 2010

During microsclerotial development in Verticillium dahliae cells of the sclerotial knot were frequently penetrated by adjacent hyphae. It is suggested that this phenomenon may be one of the factors responsible for the production of dead, protective cells normally found in mature microsclerotia of V. dahliae.
The DNA content of single cells of Micrococcus radiodurans
Authors: Driedger A. A.
Published: February 2010

Single cells of Micrococcus radiodurans may be liberated from their cell wall by a controlled treatment with lysozyme, thus making accurate cell counts possible. An average logarithmic phase cell contains 1.92 × 10−14 g of deoxyribonucleic acid (DNA).
Isolation of mutants of Candida tropicalis with increased methionine content
Authors: Okanishi M. , Gregory K. F.
Published: February 2010

Mutants of Candida tropicalis ATCC 1369, with up to 41% higher contents of methionine than the parent, have been isolated. They showed smaller increases in the sum of other amino acids. In the selection procedure, which appears to be generally applicable to food yeasts, use was made of the fact that mutants with increased levels of sulfur-containing amino acids produced smaller colonies on sulfur-deficient media than did the parental strain.
Antibody production in goat milk serum after virus instillation of goat mammary gland. V. Biochemical isolation and further characterization of antibodies to various influenza and mumps viruses
Authors: Pasieka Arthur E. , Guerin L. F. , Mitchell Chas. A.
Published: February 2010

This report describes the development of a method for the isolation of antibodies produced in the mammary gland and found in the milk after the instillation and propagation of various myxoviruses. Biochemical fractionation and isolation procedures have been modified and improved over our previous initial reports. The antibodies of the various influenza and mumps viruses that propagated in the gland were found to be associated with lactogammaglobulin. This report also demonstrates that the antibodies produced in the gland and thus given off in the milk are probably the same as those found in the blood if the animal were infected by conventional routes. Purification of the lactoglobulin protein fraction containing the antibody eliminated the non-specific inhibitors. These results were obtained from the various myxoviruses and mumps that propagated in the goat mammary gland.The main advantages of using the mammary gland as compared to using laboratory animals and their blood are as follows.1. Larger volumes of antibodies can be produced at one time (lactation period) against the influenza and mumps viruses for diagnostic and possibly for therapeutic uses.2. The animal (goat) does not appear to be affected whatsoever by the virus instillation and propagation techniques.3. The milk technique is therefore more humane towards laboratory animals. Invariably the laboratory animal does not have to be sacrificed.
Phylogenetic distribution in yeasts of the capacities for photoreactivation and for temperature-sensitive dark recovery following inactivation by ultraviolet radiation
Authors: Sarachek A. , Ireland Rosalee
Published: February 2010

Eighty-three species of yeasts representing 12 perfect and 10 imperfect genera were tested for temperature-sensitive dark recovery and for direct photoreactivation after inactivation by ultraviolet radiation (uv). With the single exception of Torulopsis inconspicua, all species exhibit temperature-sensitive dark recovery. In contrast, the ability to photoreactivate appears to be a genus-delimited characteristic. All test organisms unequivocally assignable to the genera Cryptococcus, Debaryomyces, Endomycopsis, Hansenula, Nadsonia, Rhodotorula, Saccharomyces, Sporobolomyces, Sporotrichum, and Trigonopsis photoreactivate. Photoreactivation was not observed among representatives of the genera Brettanomyces, Hanseniaspora, Kloeckera, Lipomyces, Nematospora, Pichia, Saccharomycodes, Schizosaccharomyces, or Schwanniomyces. The systematically heterogeneous genera Candida, Torulopsis, and Trichosporon include both photoreactivating and non-photoreactivating species. The evolutionary, radiobiological, and taxonomic significances of genus-independent temperature-sensitive dark recovery and of genus-dependent photoreactivation are discussed.
Genetic evidence for heterozygotes in mixed cultures of Bacillus cereus
Authors: Fraser D. K. , Baird J. P. , Kleeman J. M.
Published: February 2010

Genetically labeled strains of Bacillus cereus 569 grown together in complete medium yield from 5 to 10% colony-forming units which carry all the markers from both parents. The genetic types observed from 35 reisolated segregating colonies showed that (1) recombinants frequently constituted half or more of the progeny, (2) the association of the Sp character with the original parental genome was frequently changed, and (3) recombinants between auxotrophic loci permit the construction of a tentative map order. We conclude that genome transfer occurs by some unknown mechanism.
Production of multivalent extracellular filtrates of Staphylococcus aureus
Authors: Baman Sudhaker I. , Haque Riaz-Ul
Published: February 2010

None of the procedures currently used for producing cell-free filtrates provided preparations containing all of the extracellular products that the culture was able to produce. Even the membrane-filter technique failed to yield such preparations unless the cultures were grown on dialysis membranes laid over Brain Liver Heart Agar plates at 37 C for 48 h in an atmosphere containing 10% CO2 in air and the growth from 25 such membranes was harvested in 12.5 ml of phosphate-buffered saline. These preparations contained detectable quantities of coagulase, phosphatase, DNAse, RNAse, lipase, esterase, egg yolk factor, lysozyme, gelatinase, staphylokinase, and caseinase and were able to hemolyze human, horse, rabbit, and sheep erythrocytes. Broth and semisolid cultures, however, yielded more units of beta hemolysin than did the membrane cultures.
Serological relationships between cytoplasms of scotochromogenic mycobacteria
Authors: Kwapinski J. B. G. , Alcasid Alice
Published: February 2010

Cytoplasm preparations, obtained from 62 different strains of scotochromogenic (Runyon's group II) mycobacteria, were examined serologically with 22 different anticytoplasm sera by a macro- and microimmunodiffusion test. The most common antigenic factor was found to be shared by one-third of all the cytoplasm preparations; and one of three other major factors occurred in about one-fourth of the cytoplasms. Six strains of scotochromogenic mycobacteria possessed only a single minor antigenic factor; and cytoplasms of five other strains proved to be related to the Battey-type mycobacteria and (or) to the rapid growers. The scotochromogenic mycobacteria have been divided into seven different cytoplasm groups, with most of the strains placed in the cytoplasm groups Nos. 1, 2, and 3.
Changes in metabolic intermediates during activation of Neurospora ascospores
Authors: Eilers Frederick I. , Ikuma Hiroshi , Sussman Alfred S.
Published: February 2010

Induction of germination by either heat shock or furfural treatment results in rapid changes in a variety of metabolic intermediates. Although the changes brought about by either treatment differ somewhat, the overall changes occurring in both groups of spores may be summarized as follows: trehalose concentration decreases while the concentrations of glucose, G-6-P, F-6-P, PEP, pyruvate, ethanol, malate, OAA, ATP, NADH, and NADPH show varying degrees of increase.
Cytochemistry, morphogenesis, and tentative identification of mycetomal microorganisms of Sitophilus granarius L. (Coleoptera)
Authors: Bhatnagar R. D. S. , Musgrave A. J.
Published: February 2010

The mycetomal microorganisms of Sitophilus granarius (L.) (Coleoptera) are flexible, non acid-fast, non-flagellated rods, often surrounded by mucoid material. Pleomorphic and involution forms are present. Life cycle stages have been observed. The literature on these organisms is briefly reviewed. As they have never been cultured in vitro and the literature indicates this may be very difficult or even impossible, a postulate of Murray's regarding identification of symbiotes by morphology is invoked and the mycetomal microorganisms (plasmids, Blochmann bodies) in this insect are tentatively referred to the Myxobacterales (sens. lat.).
Cell size of Erwinia sp. as influenced by composition of medium
Authors: Grula Mary M.
Published: February 2010

Cell length of an Erwinia species in exponential growth in certain chemically defined media can vary over an approximate fourfold range, depending on the carbon source. The largest cells occurred in a glucose–aspartate medium.
Effect of puromycin, cycloheximide, and p-fluorophenylalanine on fibroma virus DNA replication
Authors: Maloney Barbara A. , Minocha H. C.
Published: February 2010

Puromycin (2 μg/ml), cycloheximide (3 μg/ml), and p-fluorophenylalanine (400 μg/ml) completely inhibited Shope fibroma virus DNA synthesis in secondary rabbit kidney cell cultures as determined by autoradiography. The inhibition was reversed when the drugs were removed from the cultures.
Bacteriocins of Clostridium perfringens. 1. Isolation and preliminary studies
Authors: Mahony D. E. , Butler M. E.
Published: February 2010

Thirty-three strains of Clostridium perfringens were screened for bacteriocin production. Four bacteriocin-producing strains were detected by plating the supernatant fluids of these cultures on all available strains of C. perfringens seeded in semisolid agar and noting zones of bacterial inhibition after subsequent incubation. The spectrum of sensitive strains differed for each bacteriocin as did the degree of bacterial sensitivity to each bacteriocin.One bacteriocin and one indicator strain were chosen for further study. This bacteriocin, which was spontaneously produced during the logarithmic growth phase of the bacteriocinogenic strain, was not inducible with ultraviolet light but was sensitive to heat and trypsin. Adsorption of bacteriocin to the indicator strain was not detected and electron microscopy did not reveal any particulate substance associated with bacteriocin activity. The degree of bacterial inhibition was dependent on the titer of the bacteriocin used, and the age of the indicator culture appeared to influence its relative response to bacteriocin treatment.
A tissue culture technique for the assay of antibacterial immune sera
Authors: Diena B. B. , Wallace R. , Kenny C. P. , Greenberg L.
Published: February 2010

A tissue culture assay method is described in which monkey kidney cell cultures were protected by antibacterial immune serum against infection by Salmonella typhi, Neisseria meningitidis, or Neisseria gonorrhoeae. The neutralization of the bacterial challenge was specific since neither heterologous nor normal sera gave significant protection to the tissue cultures.
Potassium binding, growth, and survival of an extremely halophilic bacterium
Authors: Gochnauer M. B. , Kushner D. J.
Published: February 2010

The potassium content of Halobacterium halobium was studied in media in which the K+ was growth-limiting and in media containing excess K+. In BSM medium (76.5 μg/ml K+) cells grew until all K+ was cell bound. In BSMK medium (1.1 mg/ml K+) cells grew more abundantly; about one-third of the available K+ became cell-bound. Adding glucose or vitamins to BSMK medium stimulated growth and could stimulate K+ binding. However, rapid death in the presence of vitamins reduced the potassium-binding ability of most cultures. Living cells bound very large amounts of K+. After growth stopped in BSM medium they contained about 0.4 g K+ per gram protein; that is, about 30% of the cell's dry weight consisted of K+. This is probably the lowest K+ concentration supporting life of these cells. In BSMK medium, and in the BSM medium in the early stages of growth before all K+ was cell-bound, considerably higher levels of K+ were reached. Altering the pH or the NaCl concentration of the medium within the limits that still permitted growth did not affect the cells' K+ contents.K+ was released when cells in culture died. Non-growing cells incubated at 37 °C in salts solutions without K+ or any energy source lived for up to 3 days, and with K+ for at least 7 days. Their K+ contents remained constant until they died, and then fell. If Mg2+ was omitted from the salts solution cells died more rapidly than in the absence of K+. Dead cells did not lyse or release protein into the external medium.
The effect of two herbicides (CIPC and eptam) on oxidative phosphorylation by Nitrobacter agilis
Authors: Winely C. L. , Clemente C. L. San
Published: February 2010

Using cell-free extracts of Nitrobacter agilis, we investigated the effects of CIPC and eptam on the oxidative phosphorylation coupled to nitrite oxidation as well as upon the reduced nicotinamide adenine dinucleotide (NADH2) oxidation to determine possible effects of the herbicides upon electron transport. Both CIPC and eptam exerted an uncoupling effect on the oxidative phosphorylation linked to nitrite oxidation. Although nitrite oxidation was inhibited, an intensely severe inhibition of phosphorylation caused a 50% reduction in the P/O ratio (μmoles of 32P esterified per μatom of oxygen consumed) at about 2.3 × 10−4 M CIPC and at 8 × 10−4 M eptam. Likewise, 2,4-dinitrophenol (DNP), a classical phosphorylation uncoupler, affected the oxidative phosphorylation in N. agilis. Although oxygen uptake was inhibited, a 45% reduction in the P/O ratio occurred at 2.5 × 10−4 M DNP because of a greater effect on phosphate esterification. Neither CIPC nor eptam affected reduced nicotinamide adenine dinucleotide (NADH2) oxidase activity.
Preparation of a highly active form of nisin from Streptococcus lactis
Authors: Bailey F. J. , Hurst A.
Published: February 2010

Cells of Streptococcus lactis (354/07) synthesized and retained nisin when grown in a complex medium with 2.5% glucose at a constant pH of 6.7. Nisin was extracted from cells by a previously used method with hot 0.05 N HCl but milder methods of extraction from whole and broken cells using a variety of solvents were also tested. In the preferred method broken cells were extracted with 0.05 N HCl at 2 °C. The Cl− ions of the extract were exchanged for acetate on columns of the resin Amberlite CG 4B and the eluate was concentrated by acetone precipitation at −19 °C. The nisin was finally purified by pH gradient elution from CM cellulose columns. Three peaks with antibiotic activity were found, two of the peaks were minor and represented less than 5% of the nisin. The main peak gave a single band on electrophoresis. Electrophoresis of the material from the CM cellulose peaks revealed about 44 bands of basic proteins. Nisin made by the hot or cold HCl extraction behaved similarly in electrophoresis and CM cellulose chromatography but the antibiotic activity of the material isolated from the cold extract was nine times greater than that of the material isolated from the hot extract.
An ultrastructural study of the development of a nuclear polyhedrosis virus of the eastern hemlock looper, Lambdina fiscellaria fiscellaria
Authors: Cunningham John C.
Published: February 2010

The development of a nuclear polyhedrosis virus of the eastern hemlock looper, Lambdina fiscellaria fiscellaria, is described in gut and hypodermal tissues. Infection was found in the midgut cells where a cycle of virus replication occurred but no polyhedron formation was observed. In the hypodermis the mode of viral development was similar to that recorded for other nuclear polyhedroses which have bundles of virions surrounded by membranes and occluded in polyhedra. At an advanced stage of infection, non-occluded virions formed regular arrays in some of the infected nuclei. Other non-occluded virions were found in the cytoplasm and in large numbers near the periphery of cells. Angular cytoplasmic inclusion bodies showing the structure of polyhedron protein, but containing no virions, were associated with virus-infected cells in both the tissues examined.
The synthesis of L-serine by Micrococcus lysodeikticus
Authors: Nelson Jr. J. D. , Naylor H. B.
Published: February 2010

The phosphorylated pathway was established as a biosynthetic route to L-serine in Micrococcus lysodeikticus. Evidence was based upon the demonstration of the synthesis of L-phosphoserine (PS) and serine from D-3-phosphoglyceric acid (PGA) and by the detection of phosphoglyceric acid dehydrogenase and PS phosphatase activities in crude cell-free extracts. The synthesis of PS from PGA was enhanced by L-glutamic acid and by L-lactic dehydrogenase. PS phosphatase was stimulated by added Mg2+ ion. The isolation of ser/gly− auxotrophs lacking PS phosphatase or the ability to synthesize PS from PGA confirmed the obligatory role of the phosphorylated pathway in serine biosynthesis in the organism.
The effect of cochliodinol, a metabolite of Chaetomium cochliodes, on the respiration of microspores of Fusarium oxysporum
Authors: Meiler D. , Taylor A.
Published: February 2010

Cochliodinol at 15 μg/ml reduced the respiration rate of microspores of Fusarium oxysporum, with glucose or succinate as substrate, by about 70%, and also inhibited their germination. The inhibitory effect was partially reversed by the addition of magnesium ions to the medium.
Effect of 5-bromouracil on the growth of a thymine auxotroph of Escherichia coli K-12
Authors: Jones Roosevelt J. , Hewitt Roger R.
Published: February 2010

An atypical viability response to 5-bromouracil has been observed in a thymine auxotroph of E. coli K-12. The response occurs in two phases, the first reflecting tolerance to the analogue during continued exponential growth and cell division. The second is a static phase during which viable number remains constant, while cell number and mass increase at a diminishing rate.During the latter phase filamentous cells increase in number and length. Examination of the cloning potential of cells after 10 h of growth in 5-bromouracil indicated that filamentous cells continue extension on solid medium into non-septate coils that are sterile. Other cells, presumably static when plated, readily form microcolonies free of defective members.Observed responses to penicillin, potentially stabilizing media, or added thymine suggest that 5-bromouracil evokes a bimodal response in this strain. The analogue exerts a bacteriostatic effect on some cells which remain viable for several hours. The bacteriocidal effect, presumably on cells continuing growth, interferes with cell division by preventing septation.
Effects of radiation pasteurization on Salmonella. II. Influence of repeated radiation-growth cycles on virulence and resistance to radiation and antibiotics
Authors: Previte Joseph J. , Chang Yinette , Scrutchfield W. , El-Bisi H. M.
Published: February 2010

Populations derived from Salmonella typhimurium surviving 1, 5, or 10 exposures to 0.5 Mrad did not show any increase in resistance to antibiotic discs containing 5 μg of tetracycline, 5 μg of chloromycetin, or 50 units of polymyxin. The frequency of resistance to 3 μg of tetracycline, 10 units of ampicillin, 120 μg of chloromycetin, or 30 μg of streptomycin per milliliter of agar, did not increase among progeny derived from either of two strains of S. typhimurium surviving 5–10 exposures to 0.5 Mrad. So, too, the virulence and radiation resistance of three strains of S. typhimurium exposed to radiation-growth cycling remained essentially unchanged or decreased.A mixture which originally contained 10 different serotypes of Salmonella was cycled at 0.23 Mrad. After 10 exposures the frequency of resistance of the progeny to ampicillin, chloromycetin, and streptomycin increased 87-, 55- and 13-fold respectively. The LD50 was essentially the same, but the radiation resistance (D value) increased from 0.053 Mrad in controls to 0.074 Mrad.The evidence presented seems to indicate that mutants are attained more readily from Salmonella cultures recycled at 0.25 Mrad or less than from those recycled at 0.5 Mrad. The pathogenicity of either one was usually essentially unchanged or reduced.
Identification of products produced by the anaerobic degradation of naringin by Butyrivibrio sp. C3
Authors: Cheng K.-J. , Krishnamurty H. G. , Jones G. A. , Simpson F. J.
Published: February 2010

Butyrivibrio sp. C3 degraded naringin anaerobically yielding naringenin, neohesperidose, phloroglucinol, and p-hydroxyphenylpropionic acid.
Effect of carbon–nitrogen ratios on production of perithecia by Sordaria fimicola
Authors: Hall Robert
Published: February 2010

The influence of carbon: nitrogen (atom: atom) ratios on production of perithecia by Sordaria fimicola was examined. Media contained KNO3 at concentrations of 12 mM, 24 mM, or 48 mM, and glucose or maltose at concentrations providing carbon: nitrogen ratios of 1:10, 1:1, 5:1, 10:1, 20:1, and 30:1. At each concentration of KNO3 numbers of perithecia were greatest on media with an initial carbon: nitrogen ratio of 5:1 or 10:1. There was no evidence that the effect of the carbon: nitrogen ratio on the development of perithecia was directly exerted through effects on the amount of growth, the cessation of growth, or the exhaustion of exogenous carbohydrate.
Electron microscopic studies of the rickettsia Coxiella burnetii: entry, lysosomal response, and fate of rickettsial DNA in L-cells
Authors: Burton Paul R. , Kordová Nonna , Paretsky David
Published: February 2010

The rickettsial agent Coxiella burneti was studied in cultured mouse L cells by use of the electron microscope. Rickettsiae gain entry to the host cell in an apparently passive manner through phagocytic activity by L cells. The L cells show a lysosomal response to the presence of rickettsiae, as determined by cytochemical tests for acid phosphatase and 5′-nucleotidase. Further, examination of C. burneti within lysosomes suggests that rickettsiae can be degraded by the host cell. Autoradiographic analyses using tritiated thymidine show that rickettsial DNA is largely restricted to the dense nucleoid region, and when such labeled rickettsiae are used to inoculate L cells, most of the label becomes localized in the host cell nucleus. The above information is discussed in terms of dynamic interactions between C. burneti and infected L cells.
Properties of psychrophilic bacteriophage specific for Micrococcus cryophilus
Authors: Kulpa Jr. Charles F. , Olsen R. H.
Published: February 2010

A bacteriophage infective for the obligate psychrophile, Micrococcus cryophilus, was isolated from sewage. The host range is limited to this species. Phage and host DNA are similar in G–C content. The bacteriophage has an average burst size of 290 at 20 °C and 50 at 3.5 °C. The phage is thermosensitive, being 99.9% inactivated in 5 min at 45 °C. This is the first report of the isolation of bacteriophage infective for gram-positive psychrophiles.
Release of viral hemagglutinin and nucleocapsid components after disruption of Sindbis virus with ether
Authors: Arif B. , Faulkner P.
Published: February 2010

Purified Sindbis virus is split into two components upon treatment with ether. These are (a) a hemagglutinin which sediments at 55 S and is non-infectious. This fraction was shown to be devoid of phospholipid and to contain the envelope structural protein of the virion; (b) a fraction sedimenting at 135 S, which is devoid of RNA, but contains viral nucleocapsid structural protein. This fraction may represent the RNA-less nucleocapsid of the virion.
Effect of drugs that alter excitable membranes on the motility of Rhodospirillum rubrum and Thiospirillum jenense
Authors: Faust Maria A. , Doetsch R. N.
Published: February 2010

Drugs known to block impulse transmittance, or that depolarize membranes, severely affected motility in Rhodospirillum rubrum and Thiospirillum jenense. Procain, serotonine creatinine sulfate, neostigmine methyl sulfate, eserine sulfate, atropin sulfate, parathion, acetylcholine chloride, and mersalyl acid, all were active in this respect. It is suggested that a system involving electrical potential differences in bacterial membranes may possibly play a role in bacterial flagellar motility.
Yeasts from the St. Lawrence River
Authors: Simard R. E. , Blackwood A. C.
Published: February 2010

Yeasts were isolated from 96% of samples taken from five widely separated collection points on the St. Lawrence River during the summer of 1968. Numbers varied from 0 to 9500 per 100 ml but were not correlated with depth (1-ft, 15-ft, and 30-ft depths were sampled) or to salinity. Some influence of time was noted as the numbers were considerably higher in July and somewhat higher in September. The mean numbers of yeasts isolated at Quebec were higher than the means found at the other four stations but the rank varied considerably among the times of sampling. A wide range of species was identified, 39 in 10 genera, and in addition a large number of Candida and Rhodolorula were not classified as to species. Rhodotorula glutinis was the most frequently isolated; the 'pink yeasts' made up 58% of the total isolates.
Iron uptake in Salmonella typhimurium
Authors: Walsh B. L. , Warren R. A. J.
Published: February 2010

The iron-uptake system of S. typhimurium is energy-dependent, repressed by growth in the presence of iron, and apparently specific for iron. Iron uptake is stimulated by a sideramine and by phenolic acids. In mutants unable to synthesize enterobactin, the uptake system remains functional. Iron inside the cell is not available to external chelators.
Particle size, water-stable aggregates, and bacterial populations in lake sediments
Authors: Tsernoglou D. , Anthony E. H.
Published: February 2010

Sediments from 10 lakes for which bacterial counts were available were submitted to particle size analysis (Coulter Counter), both before and after removal of organic material. While these sediments were not so highly aggregated as soils, they contained water-stable aggregates and differed from one another in this characteristic. The counter failed to detect some apparently unstable aggregations visible in the sediment of one lake. The median sizes of the untreated sediment were observed to be inversely proportional to the median sizes of the sediment from which the organic component had been removed. There was good correlation between logarithms of the heterotrophic bacterial population (culture counts) and the median sizes of the particles in untreated samples of the sediment. Estimations of bacterial density, assuming a specific gravity of 1.6 for these sediments indicated that, for the four lakes for which direct counts of bacteria were available, there were from 3000 to 15 000 bacteria per square millimeter of sediment particle surface, or about 1 bacterium for every 70 to 300 μ2.
Enzyme cytochemistry and autoradiography of adenovirus-infected cells as determined with the electron microscope
Authors: Yamamoto T. , Shahrabadi M. S.
Published: February 2010

The biochemical nature of adenovirus-induced inclusions was determined by specific enzyme digestion of thin sections combined with autoradiography using tritiated precursors.The early basophilic inclusions and the ring form inclusions were found to contain newly synthesized deoxyribonucleic acid (DNA), ribonucleic acid (RNA), and protein. The later appearing eosinophilic inclusions, both the electron light appearing ones and the electron dark appearing ones, consisted of protein.The total RNA synthesized by the infected cell was slightly increased; part of the increase was due to continuing synthesis of RNA by the nucleolus. The host DNA, after infection, was marginated along the nuclear membrane and was not subsequently incorporated into virus DNA.