bluuebunny/crossref_metadata_2025 huggingface dataset:
Association of deoxyribonuclease-sensitive material with adenovirus penton aggregates after treatment of infected cell cultures with sodium deoxycholate
Authors: Marusyk R. G. , Norrby E.
Published: February 2010

Sodium deoxycholate treatment of adenovirus-infected cell cultures was found to release rapidly sedimenting penton components with a buoyant density in CsCl of about 1.34 g/ml. The high-density penton material derived from human and simian adenovirus-infected cells occurred in monomeric form, while that derived from canine adenovirus-infected cells was in the form of non-symmetrical groupings of pentons aggregated at the vertex capsomere. Deoxyribonuclease treatment and 3H-thymidine-DNA labeling experiments revealed that the high-density of the pentons so obtained was due to a small associated segment of nuclease-sensitive material. A possible explanation of the nature of the nuclease-sensitive material is given.
The metabolism of p-fluorobenzoic acid by a Pseudomonas sp.
Authors: Harper D. B. , Blakley E. R.
Published: February 2010

A species of Pseudomonas previously used to study the degradation of p-fluorophenylacetic acid was used to investigate the degradation of p-fluorobenzoic acid. During growth on the latter substrate all organic fluorine was released into the culture medium as fluoride. Several metabolic intermediates were isolated from the culture medium of resting cells. The major compounds have been identified as 4-fluorocatechol, β-acetylacrylic acid, (+)-4-carboxymethyl-4-fiuorobut-2-enolide, (−)-4-carboxymethyl-but-2-enolide, and β-ketoadipic acid. A small quantity of a compound tentatively identified as β-fiuoroacrylic acid was also isolated. On the basis of these findings, together with respiratory studies on p-fluorobenzoic acid grown cells with various substrates, two metabolic pathways are proposed which involve elimination of fluorine at either of two alternative stages in the breakdown of p-fluorobenzoic acid.
Selection and characterization of a pleomorphic form and an L form of Bacillus pumilus NRRL B-3275
Authors: Burmeister H. R. , Hesseltine C. W.
Published: February 2010

Bacillus pumilus NRRL B-3275 cultures contained spherical, osmotically sensitive cells after incubation for 7 days in a tryptone broth containing 7% NaCl. Subcultures from cells growing in the saline broth produced only L-form colonies when plated on tryptone agar with 7% NaCl and only rod-form colonies on nutrient agar. When the tryptone agar medium was supplemented with 1.7% NaCl, colonies of cells irregular in shape and size were observed in addition to L-form and rod-form colonies. Platings from successive weekly transfers made in tryptone broth with 7% NaCl yielded an increasing proportion of L-form and pleomorphic-form colonies while the ratio of rod-form colonies declined. Cells of the pleomorphic form are morphologically distinct from both the rod form and L form but are identical with the rod form in their growth requirements.
Influence of growth of Streptomyces fradiae on pepsin-HCl digestibility and methionine content of feather meal
Authors: Elmayergi H. H. , Smith R. E.
Published: February 2010

Feather meal, fermented by a methionine-excreting mutant of Streptomyces fradiae in the presence of a mineral salts solution and glucose, was 90% digestible in acidified pepsin solution as compared with 65–70% for unfermented meal. Feeding trials with chicks, however, indicated that no significant difference in nutritional value existed between fermented and unfermented meal. Lack of product acceptability may have been partly responsible.
Physiology of sporeforming bacteria associated with insects, m. Radiorespirometry of pyruvate, acetate, succinate, and glutamate oxidation
Authors: Bulla Jr Lee A. , St. Julian Grant , Rhodes Robert A.
Published: February 2010

Oxidation of pyruvate, acetate, succinate, and glutamate was compared in Bacillus thuringiensis, B. alvei, B. lentimorbus, and B. popilliae. Cells of B. thuringiensis and B. alvei in transition from vegetative growth to sporulation oxidized these substrates by tricarboxylic acid (TCA) cycle reactions. No TCA cycle activity was exhibited by B. lentimorbus and B. popilliae cells that do not sporulate. B. popilliae decarboxylated C-1 of pyruvate and glutamate; B. lentimorbus, C-1 of pyruvate only. B. thuringiensis and B. alvei oxidized pyruvate and acetate at a much higher rate in the absence of amino acids and related compounds than when these nutrients were exogenously supplied; in contrast, there was no appreciable increase in C-1 decarboxylation of pyruvate by B. lentimorbus and B. popilliae. No nutrient effect was observed on succinate and glutamate oxidation in any of these four organisms.
Regenerative functions and microbial ecology of coral reefs. I. Assays for microbial population
Authors: DiSalvo L. , Gundersen K.
Published: February 2010

Sediments obtained from complex internal reef spaces at Kaneohe Bay, Hawaii, and Eniwetok Atoll, Marshall Is., were apparently homologous to the surface sediments of flat-bottomed aquatic environments. The sediments were heavily populated by bacteria, among which were numerous chitin- and agar-digesting species. Some bacteria and fungi from the reef sediments were capable of digesting a relatively insoluble organic residue obtained from thalli of a calcareous reef alga (Porolilhon sp.). Some elementary analyses of the reef sediments are presented for use in making comparisons of bacterial counts between stations.Arguments are made for the existence of an efficient system of mineralization based on the unique biogenic structure and high organismic diversity of coral reefs.
Incidence d'Aeromonas hydrophila chez la perche, Perca flavescens Mitchill
Authors: Vézina R. , Desrochers R.
Published: February 2010

Over a 4-month period, 450 perches (Perca flavescens) were captured in four lakes of the Eastern Townships, Québec, and examined for the presence of Aeromonas hydrophila, the causative agent of hemorrhagic septicemia. This bacterium was present in 78 perches. One hundred and eight strains of Aeromonas hydrophila were isolated from the heart, liver, and kidneys of those fishes. The study of the water quality of the lakes has shown that there is no positive relation between pollution and the incidence of Aeromonas in the perches studied.
Suppression of dual-effect mutants of the L-ribulokinase structural gene of Escherichia coli B/r
Authors: Abou-Sabe Morad
Published: February 2010

A number of extragenic suppressors for two-dual effect, polarity, and hyperinducible L-ribulokinaseless mutants were isolated and enzymatically characterized. The effect of the suppressors on L-arabinose isomerase and L-ribulokinase enzyme activities was tested using a variety of arar suppressor-carrying strains. The effect of these suppressor mutations on T4 amber and ocher mutants was also studied. Results show that low-dual-effect, i.e. polarity, araB− suppressor-carrying strains invariably have a distinct increase in the L-arabinose isomerase enzyme level, above the wild-type level, irrespective of the restoration of the L-ribulokinase enzyme activity. High-dual-effect, hyperinducible, suppressed mutants, on the other hand, were not significantly altered in their L-arabinose isomerase enzyme level. It is also found that four different T4 amber mutants were suppressible by all tested suppressor-carrying strains, while T4 ocher mutants were not. It is concluded that the suppressor mutations studied are amber-like suppressors acting at the translation level, and that both polarity mutant araB68 and hyperinducible mutant araBA87 are nonsense mutants. The phenomenon of hyperinducibility is also discussed.
The fatty acid composition of some Entomophthoraceae. III
Authors: Tyrrell D.
Published: February 2010

The fatty acid compositions of 12 Conidiobolus species were determined. The n-saturated acids comprised C12, C13, C14, C15, C16, C17, and C18, while nC16, nC17, nC18, and nC20 unsaturated acids were also present. In addition, C. heterosporus contained three saturated branched-chain acids. The correlation between these data and the classification of these fungi is discussed.
Comparison of intranasal and parenteral immunization routes for influenza in mice
Authors: Provost P. J. , DeMello G. C. , Vasington P. J.
Published: February 2010

Intranasal (IN) instillation of inactivated influenza vaccines was compared in mice with parenteral immunization routes, intraperitoneal (IP) and subcutaneous (SC). Overall results of direct lethal challenges indicated IN and IP to be about equally effective immunization routes and both superior to SC. However, in certain cases especially with B/Massachusetts/3/66, the SC route compared favorably with IN and IP, showing that no broad generalization can be applied to all types of influenza. Study of neutralizing antibody levels in serum and bronchial washings failed to differentiate IN and SC vaccination. Serum antibody levels were low and no antibody activity was found in bronchial washings.
Flagellar activity in an aquatic bacterium
Authors: Strength W. J. , Krieg N. R.
Published: February 2010

The bipolar flagellar fascicles of a gram-negative, floc-forming, aquatic rod were studied. Each fascicle consisted of up to 11 individual flagella of 19-nm diameter with separate insertion sites in the cell wall. Fascicles exhibited three modes of behavior as illustrated by darkfield cinematography, (a) Extended helical fascicles exhibited wave propagation from base to tip at varying speeds with temporary stopping. (b) A fascicle could be retracted into the form of a polar coil as if it were a spring, the process beginning at the distal end and proceeding proximally. Fascicles could be reextended by reversal of this process. (c) An extended fascicle could bend at its base until it lay adjacent to the cell wall. This was preceded by an increase in wavelength and amplitude at the distal end which progressively affected the entire fascicle. After bending, a fascicle could swing back out again into the extended configuration. Despite the intense activity of the flagellar fascicles, the cells were found to be unable to swim about. Several possible explanations for this lack of motility are discussed. The unusual features of the flagellar activity are related to current concepts of the mechanisms of flagellar motion.
Emesis and diarrhea induced by enterotoxin of Clostridium perfringens type A in monkeys
Authors: Hauschild A. H. W. , Walcroft M. J. , Campbell W.
Published: February 2010

Preparations of enterotoxin of Clostridium perfringens type A, purified by gel filtration and administered into the stomach of cynomolgus monkeys, induced emesis and diarrhea. The gastrointestinal activities of the preparations were completely neutralized with enterotoxin-specific antiserum.
A simple method for enumeration of antibiotic-producing microorganisms in the rhizosphere
Authors: Neal Jr. J. L.
Published: February 2010

A simple method for enumerating antibiotic-producing microorganisms in the rhizosphere using the plate-dilution frequency technique is described. The method is suited for large-scale assays common to rhizosphere studies and is useful for detecting antibiotic-producing microorganisms, which may be numerically low in proportion to the total rhizosphere microbial population.
Cutaneous skin test for delayed hypersensitivity in hamsters to viral induced tumor antigens
Authors: Olsen Richard G. , McCammon James R. , Weber Joseph , Yohn David S.
Published: February 2010

A skin test was used to monitor the delayed-type hypersensitivity immune response in hamsters to Rous Sarcoma, Adenovirus-12, and SV-40 virus induced tumor antigens. The virtual absence of cross-reactions to heterologous tumor antigens confirmed the immunologic specificity of the dermal skin test. In tumor-challenged hamsters a positive skin test was evident about the time the transplanted tumor became palpable and persisted during tumor growth.
Bacterial flora of phyto- and zoo-plankton in the inshore water of Japan
Authors: Simidu U. , Ashino K. , Kaneko E.
Published: February 2010

Generic composition of aerobic bacterial flora of plankton was compared with that of seawater. More than 70% of the heterotrophic bacteria from most of the plankton samples were Vibrio and Aeromonas, while the percentage of occurrence of these genera in the seawater flora was about 45%. The assumption that some Vibrio and Aeromonas are closely associated with marine organisms was discussed.
The effect of temperature on lysis of cells and cell walls of Bacillus psychrophilus
Authors: Mattingly Stephen J. , Best Gary K.
Published: February 2010

Cells of Bacillus psychrophilus lysed rapidly when suspended in carbonate or phosphate buffer at a temperature above the maximum growth temperature (30C). This lysis was found to be temperature dependent. The effect of various inhibitors of whole cell lysis was examined. D-Serine, CaCl2, sucrose, and polyethylene glycol were found to be quite effective in inhibiting lysis at 37C. However, this inhibition seemed to be nonspecific. Lysis of isolated cell walls of this psychrophile was also found to be temperature dependent. Lysis was linear and zero order throughout the growth range of this organism. However, as the temperature was increased (37 and 45C) the rate of lysis increased rapidly and zero-order kinetics was lost at these elevated temperatures. D-Aspartic acid was the most effective inhibitor of cell wall lysis. However, its action was only apparent at temperatures above the maximum growth temperature. These results suggest that the cell wall of B. psychrophilus is unusually heat labile and indicate a novel mechanism of lysis.
Disruption of Bordetella pertussis in the Ribi Cell Fractionator. 1. Effect of different pressures
Authors: Hollinger E. , Wardlaw A. C.
Published: February 2010

Exposure of B. pertussis in pH 7.0 phosphate buffer to disruption in the Ribi Cell Fractionator (RCF) at a series of increasing pressures caused progressive lysis as judged by the decrease of optical density and by the release of protein and DNA into the 20 000 g supernatant. A plateau of maximum lysis was reached around 20 000 psi, although DNA continued to be released from the cell residues up to 30 000 psi. The 20 000 g residues (cell envelopes) from 30 000 psi lysates comprised, after pH 7.0 washing, about 30% of the dry weight of the original cells and contained about 30% of the original protein and 14–27% of the original DNA. They contained the greater part (80–90%) of the original lipopolysaccharide (LPS) and between one-half and two-thirds of the histamine-sensitizing factor(HSF)and protective antigen (PA). However, the 20 000 g supernatant fractions also contained HSF and PA. Thus although HSF and PA were not destroyed by RCF treatment, it was not possible to get efficient cell disruption in pH 7.0 phosphate buffer without causing release of one-third or more of the HSF and PA into the cytoplasmic fraction.
Flocculation in a fission yeast: an initial step in the conjugation process
Authors: Calleja G. B. , Johnson B. F.
Published: February 2010

Schizosaccharomyces pombe NCYC 132, a haploid strain not previously observed to conjugate and sporulate, formed floes during stationary phase when grown aerobically in malt extract broth. Flocculation was followed by sexual conjugation and sporulation. Cultural conditions which prevented the induction of flocculation, such as anaerobiosis or growth in minimal salts medium, also prevented conjugation and sporulation.
Estimation of an equivalent "12D" process by the normal distribution method
Authors: Anellis Abe , Werkowski Stanley
Published: February 2010

A new statistical approach is suggested, and illustrated, for estimating an equivalent "12D" irradiation process based upon survival curves or partial spoilage data which appear to follow a normal instead of an exponential distribution. Application of this method to partial spoilage data derived from five individual inoculated ham packs gave more reasonable results than those computed by the conventional method based upon exponential death kinetics.
Phylogenetic significances of the photoreactivable sectors of species of Hansenula
Authors: Sarachek A. , Ireland Rosalee
Published: February 2010

Each species of the genus Hansenula has been tested for the extent to which cellular inactivation by ultraviolet radiation is mitigated by photoreactivation. The values obtained conform to a pattern consistent with the phylogenetic relationships between the species proposed by Wickerham. These findings corroborate previous indications that (i) fixation of the capacity for photoreactivation is an important element in the evolution of yeasts and that (ii) opportunity for environmental exposure of yeasts to solar ultraviolet radiation is not the determining factor in natural selection for their abilities to photo-reactivate.
Purification of epidermidins, new antibiotics from staphylococci
Authors: Hsu Chun-Yang , Wiseman G. M.
Published: February 2010

Antibiotics from the 29297 and 36534 strains of Staphylococcus epiderinidis were purified by treatment with acid and barium hydroxide, followed by precipitation with zinc chloride which separated the active principles into two components. These were designated the zinc-precipitable and zinc-soluble fractions. The use of Dowex and (or) Sephadex G-15 further increased the specific activity of these antibiotics. All fractions of both antibiotics were crystallized from aqueous solutions. Recrystallization and methanol precipitation of the antibiotics brought the specific activity to a relatively constant value. The generic name, epidermidin, is proposed for these antibiotics and 29297 zinc-precipitable and zinc-soluble components are designated epidermidins A1 and A2, while the equivalent 36534 fractions are epidermidins B1 and B2 respectively.
The physiology of production of the antibiotic cyathin by Cyathus helenae
Authors: Johri B. N. , Brodie H. J.
Published: February 2010

The maximum production of cyathin occurred when Cyathus helenae was grown in static surface culture. The yields of cyathin were high on a semisynthetic medium as well as on a chemically defined medium developed during this study. The concentration of sugar in either medium determined the yield of cyathin. Of the micronutrients tested, zinc had a stimulatory effect on the production of cyathin. A pH range of 4.5 to 5.5 and temperature of 22 °C were the best combination for maximum yield of cyathin. Of the seven vitamins tested, only riboflavin influenced the cyathin production.A study of various nitrogen sources showed that C. helenae grew better on organic nitrogen; nitrates enhanced cyathin production considerably without an appreciable change in the growth of the fungus. Dextrose, fructose, maltose, and starch all proved to be good sources of carbon for the production of cyathin.
Seawater salts – hydrostatic pressure effects upon cell division of several bacteria
Authors: Albright Lawrence J. , Henigman John F.
Published: February 2010

An increased concentration of seawater salts increased the maximum hydrostatic pressure allowing cell division of the marine bacteria Achromobacter aquamarinus, Micrococcus sedentarius, Serratia marinorubra, and Vibrio adaptants. Increased concentrations of these salts did not have as great an influence on the maximum hydrostatic pressure for cell division of Escherichia coli and Micrococcus luteus, which were isolated from a terrestrial environment.
Yeasts of the Matador soils of Saskatchewan and their ability to use flavonoids
Authors: Spencer J. F. T. , Babiuk L. , Morrall R. A. A.
Published: February 2010

The numbers of yeasts of the soils of the Matador site of the International Biological Program, in southern Saskatchewan, varied from about 1400 to 10 000 cells/g soil in the surface layer and from 600 to 1800 cells/g in the subsurface layers. Most of the cultures isolated were Cryptococcus albidus and its variety diffluens, Cryptococcus laurentii, and Cryptococcus terreus. A few cultures of Cryptococcus dimennae, Rhodotorula minuta, Sporobolomyces pararoseus, and Sporobolomyces salmonicolor were also isolated. Most of the cultures isolated could use rutin and many of them used the other flavonoids tested. Many of them used phloroglucinol and a few used naphthalene.
A disulfide reductase in spores of Bacillus cereus T
Authors: Blankenship Leroy C. , Mencher J. R.
Published: February 2010

An enzyme obtained from Bacillus cereus T spores which catalyzes the reduction of the disulfide, 5, 5′-dithiobis (2-nitrobenzoic acid) (DTNB), has been partially purified and characterized. The enzyme required either reduced nicotinamide adenine dinucleotide phosphate (NADPH2) or reduced nicotinamide adenine dinucleotide (NADH2) as electron donor. It had a pH optimum of 8, was destroyed by heating at 70C for 5 min, and was stimulated by Ca2+ and Mg2+. No other small molecular weight disulfides were found to be substrates for the enzyme.
Metabolism of chloramphenicol by the producing organism. Some properties of chloramphenicol hydrolase
Authors: Malik V. S. , Vining L. C.
Published: February 2010

A cell-free enzyme preparation which catalyzed the hydrolysis of chloramphenicol was obtained from Streptomyces species 3022a, a chloramphenicol-producing actinomycete. The enzyme was difficult to release from the mycelium and had low substrate affinity (Ks 0.2 mM) and activity (Vmax 2.86 nmoles/h) towards chloramphenicol. Activity was present in chloramphenicol-sensitive non-producing cultures not previously exposed to the antibiotic and did not increase during development of resistance. The results suggest that inactivation of chloramphenicol may be a subsidiary function of the enzyme.
Effect of nutritional factors on DDT-degradation by Mucor alternans
Authors: Anderson J. P. E. , Lichtenstein E. P.
Published: February 2010

The effects of nutritional factors on the capacity of Mucor alternans to degrade 14C-DDT in shake cultures were investigated. Fungal spores did not grow in media that contained DDT as the sole carbon source, but they remained viable over a 2-month period and developed into a mycelium, once glucose had been added. The degradation of DDT by the fungus was not related to the mycelial mass. The quantity of water-soluble metabolites produced from DDT was, to some extent, dependent on the insecticide concentration, but largely on the carbon and nitrogen sources in the culture media. Largest quantities of the metabolites were formed with glucose and ammonium nitrate. The concentration of glucose affected this metabolism quantitatively. With the exception of ribose, growth on other sugars resulted in a decrease in the production of DDT-metabolites, which was most noticeable when maltose was used. No qualitative differences in the metabolites were observed. When ammonium nitrate was replaced with other nitrogen sources, the production of water-soluble metabolites was substantially reduced (35 to 75%) and qualitative differences in the appearance of metabolites were also observed.
Inducible pectate lyase synthesis and phytopathogenicity of Pseudomonas fluorescens
Authors: Zucker Milton , Hankin Lester
Published: February 2010

A strain of Pseudomonas fluorescein which synthesizes large quantities of an inducible extracellular pectate lyase proved to act as a virulent soft rot organism on potatoes, whereas a parent strain that synthesized no lyase showed little pathogenicity. The procedure for inducing lyase synthesis involves culture of P. fluorescens for at least five generations on a combined carbon source of pectin plus a factor extracted from acetone powders of potatoes. The extracted factor is dialyzable and heat-labile but can be sterilized by Millipore filtration. When soil was inoculated into the induction medium, microorganisms present synthesized pectate lyase.Less than half of the single colony isolates obtained by plating out induced cultures of P. fluorescens synthesized pectate lyase when reinoculated into induction medium. Serial reisolation and reinoculation of induced cultures failed to increase the proportion of induced cells. This failure suggests that inducibility is lost during growth of cells on induction medium and (or) on solid agar used for plating. Under similar conditions, cultures of Erwinia carotovora contained induced cells only. The apparent loss of inducibility that occurs in P. fluorescens may account for its generally saprophytic behavior in nature.
The value of 21 amino acids as nitrogen sources for Phytophthora cactorum and P. heveae
Authors: Leal J. A. , Gallegly M. E. , Lilly V. G.
Published: February 2010

The value of 21 amino acids as nitrogen sources for Phytophthora cactorum (Leb. and Cohn) Schroet. and P. heveae Thompson has been studied using the dry weights of mycelium, changes in the pH values of the culture media, and the accumulation of ammonium nitrogen in the culture media as the criteria. Two concentrations of each amino acid were used to furnish 106 and 424 mg N/liter. The three parameters mutually supported each other in dividing the amino acids into two groups, poor and good.The following amino acids were poor sources of nitrogen for both species: L-hydroxyproline, L-isoleucine, L-leucine, L-lysine, L-methionine, and L-tryptophan. L-Phenylalanine was a good amino acid for P. cactorum, and a poor amino acid for P. heveae. L-Cysteine and L-valine were good sources of nitrogen for P. heveae, but poor nitrogen sources for P. cactorum. The following amino acids were good sources of nitrogen for both species: L-α-alanine, L-arginine, L-asparagine, L-aspartic acid, L-glutamine, L-glutamic acid, glycine, L-histidine, L-proline, L-serine, L-threonine, and L-tyrosine.
Recovery of metabolic activity in Escherichia coli following limited exposure to myxin
Authors: Lesley S. M. , Behki R. M.
Published: February 2010

Exposure of Escherichia coli to myxin results in the inhibition of DNA synthesis and the cells are killed rapidly. The results presented here indicate that after a short exposure, the removal of myxin allows DNA synthesis to be renewed at the normal rate for a significant period of time before DNA synthesis is again inhibited. This metabolic recovery of DNA synthesis has been shown to be dependent on protein synthesis occurring both during and after exposure to this antibiotic. The protein involved may be one of the DNA-repair enzymes known to be present in these cells. The lethal effect of myxin, therefore, is not due to inhibition of DNA synthesis directly but is probably the result of irreparable damage to the DNA template. This interpretation is supported by the results of similar experiments showing the metabolic recovery of RNA synthesis, which follows a pattern almost identical with that seen with DNA.
Immunization with autogenous rumen enterococci
Authors: Hartman Paul A. , Jacobson Norman L.
Published: February 2010

Substantial amounts of circulating antibodies to rumen enterococci were produced in a steer by using a course of immunizations with dead and live cell suspensions. The rumen population of enterococci for which the immunity was specific was depressed only transiently, if at all. These results indicate that the numbers of rumen enterococci are not influenced by serum antibody levels.
A comparison of use of carbohydrate, cell structure, and toxin formation in naturally occurring and thymine-requiring Staphylococcus aureus strains
Authors: Repentigny J. De , Mathieu L. G.
Published: February 2010

Among a number of carbohydrates studied, glucose, fructose, and sucrose were found to support adequate growth in five Staphylococcus aureus strains selected for their different properties: toxinogenic Wood 46, auxotrophic Wood 46 thy−, encapsulated Smith, penicillin-resistant Saskatchewan 755, and non-toxinogenic and coagulase-negative SA-13.In all these strains, the analog 2-deoxy-D-glucose (deGlc), when included in the culture medium inhibited growth by blocking the use of sucrose or fructose almost completely; D-glucose restored normal growth. A Wood 46 thy− strain was more specifically used to study the effects of deGlc on "balanced and unbalanced" growth and formation of toxin. When added at the beginning of the logarithmic phase of growth in the presence of thymine, deGlc lowered the growth rate of the cells; on the other hand, as expected, penicillin (affecting formation of cell wall and used here for comparison purposes) had a truly killing effect. Thymineless death associated with "unbalanced" growth was inhibited by deGlc and this inhibition was not significantly reversed by glucose. The cells were observed under the fluorescence microscope, after staining with conjugates of rhodamine and lysozyme, as well as with those of fluorescein and anti-Staphylococcus aureus rabbit serum. When grown in the presence of deGlc, the cells were seen as unevenly stained fluorescent dots, while some of those treated with penicillin or undergoing thymineless death appeared as large and amorphous fluorescent bodies, unlike the untreated cells; such changes due to deGlc or penicillin could possibly involve carbohydrate-containing antigens (e.g., mucopeptide and teichoic acid). The results obtained with the use of various standard techniques to detect toxin indicated that toxin formation is inhibited by deGlc, apparently not selectively but proportionately with growth.
An evaluation of three agents for eluting adsorbed enterovirus from millipore membrane filters
Authors: Konowalchuk Jack , Speirs Joan I.
Published: February 2010

Several concentrations of yeast extract, beef extract, and fetal bovine serum were compared for ability to elute adsorbed coxsackievirus B5 and poliovirus 1 from HA cellulose nitrate Millipore membrane filters. Elution improved with increases in concentration of eluting agent and volume of eluent. The eluent of choice was undiluted fetal bovine serum because it was compatible with cells and showed a high degree of elution. A 5-ml serum eluate resulted in the recovery of 80–90% of the virus adsorbed by a filter from an infected buffered saline sample.
Growth of fungi on an inorganic medium
Authors: Mirocha C. J. , DeVay J. E.
Published: February 2010

A species of Cephalosporium and another of Fusarium were grown for 5 years on a medium devoid of any known, complex, organic carbon source. The organisms were grown on a solid as well as in a liquid medium and the growth rates under various conditions, based on increase in spore number and dry weight, were recorded. At initial stages of growth, there was a linear relationship between the rate of growth and CO2 gas and (or) HCO3− supplied. Direct evidence for assimilation of C14 from C14O2 was demonstrated through combustion analyses. Nitrogen supplied as either NH4Cl or KNO3 supported growth and C14O2 fixation. Although grown as heterotrophs, both species of fungi retained their ability to grow autotrophically or mixotrophically. Laboratory air, purged through sulfuric acid to eliminate trace organic contaminants from the air, supported growth of the Cephalosporium sp.
Induction of adventitious roots by culture filtrates of the hairy root bacterium, Agrobacterium rhizogenes
Authors: Hopkins D. L. , Durbin R. D.
Published: February 2010

Cell-free culture filtrates of Agrobacterium rhizogenes significantly increased adventitious root initiation in a mung bean hypocotyl bioassay. These filtrates were most active from cultures at their maximum cell density; the root-inducing activity declined rapidly after this time. The contents of cells disrupted by sonification were not active nor did they increase the activity of a 6-day-old culture filtrate. The root-inducing factor was heat stable, apparently dialyzable, and antagonized by kinetin. The 3-indole-acetic acid concentration of the culture filtrates was not high enough to account for the number of roots formed.
Selective sorption of bacteria from seawater
Authors: Marshall K. C. , Stout Ruby , Mitchell Ralph
Published: February 2010

A sequence of sorption of different bacterial types has been observed both on glass slides and electron microscope grids immersed in seawater for periods of up to 24 h. A comparison of morphological groups of bacteria initially attracted to a surface with those subsequently adhering firmly to the surface suggests a selective irreversible sorption of small rods. Firm adhesion of bacteria in the time periods considered does not indicate pili or holdfast structures. The ability of bacteria to produce extracellular polymeric fibrils may be important in such selective sorption.
Bacteriocins of Clostridium perfringens. 2. Studies on mode of action
Authors: Mahony D. E. , Butler M. E. , Lewis R. G.
Published: February 2010

The effects of bacteriocin 28 on sensitive strains of Clostridium perfringens are further described. Two indicator strains were chosen for detailed study. These strains, when treated with bacteriocin, were induced to produce spherical forms devoid of cell wall. The efficiency of conversion to spheroplasts in one strain was greatly enhanced when the organism was grown in 0.3 M sucrose broth. Sucrose, itself, was capable of inducing spheroplast formation in the other strain in the absence of bacteriocin, this being the only indicator strain observed to behave in this manner.Bacteriocin could not induce spheroplast formation when indicator bacteria were either heavily irradiated with ultraviolet light or when the culture was vigorously aerated, suggesting that metabolically active cells were required for the conversion phenomenon. When bacteriocin-treated cultures were plated on sucrose containing media, L-form colonies developed.Spheroplasts induced by bacteriocin could no longer adsorb a specific bacteriophage, which suggested that there might be a loss of cell wall receptors. Although the bacteriocin is sensitive to trypsin, it was impossible to reverse bacteriocin activity on sensitive cells by subsequent treatment with trypsin. Radioactive isotope incorporation revealed that cells treated with bacteriocin continued to synthesize DNA, RNA, and protein.
The genetic control of the two types of mannan produced by Saccharomyces cerevisiae
Authors: Spencer J. F. T. , Gorin P. A. J. , Rank G. H.
Published: February 2010

The two mannans formed by different strains of Saccharomyces cerevisiae give proton magnetic resonance spectra (spectral types A and B), which suggests that they differ principally in the presence of a-(1 → 3)-linked mannopyranosyl end units of the side chains of the more complex type (giving spectral type B). The presence or absence of such end units was under the control of a single mendelian gene, since the two types of mannan segregated independently during sporulation. The gene controlling this type of mannan produced was apparently not linked to those controlling the requirements for adenine, uracil, leucine, or histidine. The implications of the findings concerning the mechanism of biosynthesis of yeast mannan are discussed.
Growth of Xanthomonas campestris is not simply nutrient-limited
Authors: Moraine Reuven A. , Rogovin Peter
Published: February 2010

Successful use of urea as supplemental nitrogen source shows that growth of Xanthomonas campestris is not simply nutrient-limited. While distillers' solubles concentration determines initial growth rate, other factors cause growth to stop.
Rapid detection of Clostridium perfringens enterotoxin by a modified ligated intestinal loop technique in rabbits
Authors: Hauschild A. H. W. , Hilsheimer R. , Rogers C. G.
Published: February 2010

The ligated intestinal loop technique in rabbits for the assay of Clostridium perfringens enterotoxin was improved by decreasing the incubation time from about 6 h to 90 min, and keeping the animal under anaesthesia during this period.The fluid volumes were significantly higher in loops injected with enterotoxin than in loops injected either with saline or with a mixture of enterotoxin and specific antiserum. These differences were mainly due to a net loss of fluid from the control loops.
Morphactin influences sexual and asexual reproduction in fungi
Authors: Harman G. E. , Khan A. A. , Drury R. E.
Published: February 2010

It has been reported that fungi are not affected morphologically by morphactins. We found, however, that levels of perithecial formation by Nectria haematococca and pycnidial formation by Ascochyta pisi were strikingly lowered by concentrations of morphactin not inhibiting or only slightly inhibiting vegetative growth. Photo- or geo-tropism of Phycomyces blakesleeanus was not affected, and there was no evidence for interference by morphactin in the light reactions stimulating perithecial production by Nectria haematococca.
Cellular fatty acids of nonpathogenic Neisseria
Authors: Lambert Mary Ann , Hollis D. G. , Moss C. W. , Weaver R. E. , Thomas M. L.
Published: February 2010

The cellular fatty acid composition of 33 strains representing 15 species of nonpathogenic Neisseria was examined by gas–liquid chromatography. Each isolate was characterized by standard biochemical and cultural methods. Media composition influenced both the qualitative and quantitative fatty acid content of some strains examined. However, on the basis of their fatty acid composition, the species formed the same general groups regardless of the media used. N. flavescens, N. canis, N. subflava, N. flava, N. sicca, N. perflava. N. cuniculi, N. mucosa, and N. cinerea formed one fairly homogeneous group with similar fatty acid composition. Palmitic, a monoenoic 16-carbon, a monoenoic 18-carbon, β-hydroxylauric, lauric, and myristic acids were the major fatty acids present and constituted 85–90% of the total fatty acids found. N. lactamicus grown in trypticase soy broth (TSB) could be included with this general group, but it differed from all other species when grown on plates of Difco GC medium base with 1% defined supplement (GCBDS). N. catarrhalis, N. caviae, and N. ovis formed a second homogeneous group which was characterized by the presence of decanoic acid in addition to the fatty acids found in the other species. The members of this second group were further characterized after growth on GCBDS plates by the presence of large amounts of monoenoic 17-carbon acid. N. denitrificans and N. haemolysans lacked β-hydroxylauric acid, a fatty acid which has been found in relatively large amounts in over 100 isolates of various Neisseria species examined in this laboratory.
Purification and properties of a chlamydial hemagglutinogen
Authors: Sayed H. , Wilt J. C.
Published: February 2010

A hemagglutinogen was isolated from the soluble antigens of a 6BC strain of psittacosis grown in cell culture. The antigen, which was purified by chromatography and electrophoresis, has a molecular weight of 100 000 to 120 000 and a density of 1.235 at 4 °C. The serologic activity of the hemagglutinogen was not affected by acid hydrolysis but was decreased by neuraminidase treatment. It reacted more strongly with homologous than with heterologous antiserum, which might suggest the presence of more than one antigen in the preparation not separable on the basis of molecular weight, density, or electro-phoretic mobility in polyacrylamide gel. A possible alternative explanation would be the presence of a group- and type-specific activity on the same molecule.
Induction of sporangia in Phytophthora cinnamomi by a substance from bacteria and soil
Authors: Ayers William A.
Published: February 2010

Production of sporangia of Phytophthora cinnamomi on agar–mycelial disks in a mineral salts solution was induced by extracts of a soil pseudomonad. Acetone extracts of soil and of mixed populations of microorganisms from soil solution also stimulated the formation of these asexual reproductive structures. Active extracts stimulated sporangium production in aqueous dilutions as high as 10−9. Some extracts of the bacterium were less active at dilutions above or below a certain optimum concentration range. The unidentified, active substance was characterized as a nonvolatile, polar, heat-stable compound that is soluble in water and several organic solvents. Salts of Ca, Mg, K, and Fe in the suspending medium favored a limited production of sporangia in the absence of active substance, and abundant sporangia in its presence. Ca2+was essential for maximum response. The substance was detected by bioassay on paper and thin-layer chromatograms, and it was obtained partially purified.
Protein synthesis by cell-free extracts of Proteus vulgaris
Authors: Backler K. L. , Inniss W. E.
Published: February 2010

A cell-free protein-synthesizing system from Proteus vulgaris was developed and characterized. Initially, a very low activity was found to occur; it was shown to be due to a deficiency in the endogenous transfer ribonucleic acid (tRNA) content of the cell extracts. When tRNA was added to the polyuridylic acid (poly U) directed system, incorporation of 14C-phenylalanine into polypeptide readily occurred. This incorporation was dependent on ribosomes and supernatant fraction and the optimum concentrations of the various components of the system were found to be as follows: 120 μg/ml tRNA, 30 mM magnesium, 0.5 mM spermidine, 60 mM potassium, 50 mM adenosine triphosphate (ATP), 5 mM guanosine triphosphate (GTP), 0.03 mM cytosine triphosphate (CTP) and uridine triphosphate (UTP), 5 mM phosphoenolpyruvate (PEP), 50 μg/ml poly U, and 30 mM 2-mercaptoethanol.
Thickened cell walls of Bacillus cereus grown in the presence of chloramphenicol: their fate during cell growth
Authors: Chung K. L.
Published: February 2010

Bacillus cereus incubated for 4 h in a synthetic medium containing chloramphenicol was observed to form cell walls 2 to 3 times as thick as those from control cells growing in the same medium containing no antibiotic. Then the cells were washed and reincubated in fresh synthetic medium and the ultra-structural changes in the thickened walls during cell growth and elongation were examined by electron microscopy. After incubation for 20 min, multiple ruptured sites and internal fractures appeared randomly on the surface of the thickened cell wall. Large and small pieces of thickened wall fragments soon "peeled off" from the surface, leaving behind a deeper layer of wall material. Normal cell growth and elongation resumed after partial removal of the thickened cell wall. After several generations, thickened wall fragments were not observed on the surface of daughter cells.
Structural changes in cells of Clostridium sporogenes infected with a long-tailed bacteriophage
Authors: Hoeniger Judith F. M. , Bradley David E.
Published: February 2010

The infective process of phage F1 in Clostridium sporogenes has been studied by the electron microscopy of negatively stained preparations and, mainly, of thin sections. The phages adsorbed to the host wall by their tails. The first visible cytological changes accompanying intracellular multiplication were in the nucleoplasm, which became progressively fragmented into smaller units. Phage particles developed within the nuclear regions forming regular arrays of heads. When sectioned longitudinally, the elongated heads occurred in several rows; in transverse section, they were hexagonal and formed "crystalline" aggregates. Lysis occurred gradually, and was caused by the breaking away of portions of the cell envelope (cell wall and plasma membrane). During early lysis the rows of phage heads remained intact, only dispersing with time. The contents, and presumably free phage, leaked out through holes in the cell.
Association of chloramphenicol resistance of group A streptococci with host-controlled restriction and modification of bacteriophages
Authors: Friend Patric L.
Published: February 2010

Bacteriophages grown on chloramphenicol (CM)-sensitive group A streptococci plate efficiently only on other CM-sensitive strains, while phages propagated on CM-resistant strains plate well only on CM-resistant hosts. Data are presented showing that the phages are subject to host-controlled modification and restriction, and that these processes are related to the CM resistance level of the host.
Genetic evidence for "Darwinian" selection at the molecular level. III. The effect of the suppressive factor on nuclearly and cytoplasmically inherited chloramphenicol resistance in S. cerevisiae
Authors: Rank G. H. , Bech-Hansen N. T.
Published: February 2010

Four nuclear and two cytoplasmic chloramphenicol-resistance markers were selected in S. cerevisiae. The effect of the suppressive factor (abnormal mitochondria deoxyribonucleic acid) on the inheritance of these markers was studied. Nuclear markers were shown to be unaffected by the suppressive factor, in contrast to the loss of cytoplasmically inherited chloramphenicol resistance upon the generation of the suppressive factor.
Comparative studies of an asporogenic mutant and a wild type strain of Clostridium botulinum type E
Authors: Emeruwa A. C. , Hawirko R. Z.
Published: February 2010

An asporogenic mutant of Clostridium botulinum type E, ATCC 9564, was recovered on liver veal agar, which had been supplemented with MnSO4 (0.13 mM) and mercaptoacetate (0.2%). Growth in TPG measured by optical density increased exponentially for the two strains during the first 11 h. But subsequently, the optical density of the wild type rapidly declined while the sp− mutant showed a more gradual decrease. The pH decreased significantly during growth but remained unaltered at pH 5–6 during sporulation. The DPA synthesis in the sp+ strain paralleled the appearance of refractile spores, while the sp− strain showed no measurable amounts of DPA. Protease and antibiotic activities were detected late in the log growth phase of the wild type. Gas–solid chromatography showed that during growth and sporulation the mercaptoethanol and CO2 content declined significantly in the wild type, but remained unchanged in the sp− mutant, whereas N2O was evolved concurrently with sporulation. This study has provided us with an effective method for the isolation of asporogenic mutants of C. botulinum, as well as a basis for the analysis of the events which occur during the stages of sporulation.
A serological method for the identification of Spirilla
Authors: McElroy L. J. , Krieg N. R.
Published: February 2010

Antisera specific for Spirillum thermolabile antigens (TLA) of 29 Spirillum strains were obtained by adsorption of antisera prepared against unheated cells with homologous heat-treated cells. Each antiserum was tested against all of the Spirillum strains by cross-agglutination. Cross-agglutinations occurring at serum dilutions of 1:160 and above were considered indicative of a sufficient degree of antigenic relationship to permit serological grouping, and the antigenic relationships within such groups were supported by adsorption tests. The TLA antisera were used successfully to identify unknown Spirillum isolates. The high specificity of Spirillum TLA antisera allowed serological distinction of most of the species of Spirillum from one another and from members of related genera.
An analysis of the odorous constituents produced by various species of Phellinus
Authors: Collins R. P. , Halim A. F.
Published: February 2010

An examination of the odorous constituents produced by Phellinus was carried out using gas chromatography and infrared spectrometry. The predominant compound in all three species was methyl benzoate although significant amounts of methyl salicylate and benzyl alcohol were also found.
Morphologie des phages de lysotypie de Salmonella paratyphi B (schéma de Felix et Callow)
Authors: Ackermann H.-W. , Berthiaume L. , Kasatiya S. S.
Published: February 2010

The phages belong to the conventional morphological groups A1, B1, and C1. They have octahedral heads and either contractile, long non-contractile, or short tails. Our findings confirm the validity of the Felix and Callow typing scheme. Preparations of phage Beccles have been shown to contain abnormal particles such as tail tubes of various lengths, either with or without heads and tail sheaths. Some may even possess two tail sheaths. Isolated sheaths aggregate spontaneously into chains. Preparations of phage Jersey contain numerous phage tails of abnormal lengths and a few complete phages with elongated tails.