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PubMed1965

COFACTOR-DEPENDENT ALDOSE DEHYDROGENASE OF RHODOPSEUDOMONAS SPHEROIDES.

Niederpruem, Donald J. (University of California, Berkeley), and Michael Doudoroff. Cofactor-dependent aldose dehydrogenase of Rhodopseudomonas spheroides. J. Bacteriol. 89:697-705. 1965.-Particulate enzyme preparations of cell extracts of Rhodopseudomonas spheroides possess constitutive dehydrogenase and oxidase activities for aldose sugars, reduced nicotinamide adenine dinucleotide (NADH(2)), and succinate. The dehydrogenation of aldoses requires an unidentified cofactor which is not required for the oxidation of succinate nor of NADH(2). The cofactor is present in the particulate fraction of aerobic cells, but is unavailable to the enzyme system. It can be liberated by boiling or by treatment with salts at high concentration. The cofactor also appears in the soluble fraction of aerobic cells, but only after exponential growth has ceased. Extracts of cells grown anaerobically in the light possess the apoenzyme, but not the cofactor, for aldose oxidation. Cofactor activity was found in extracts of Bacterium anitratum (= Moraxella sp.) but not in Escherichia coli, Pseudomonas fluorescens, yeast, or mouse liver. In 0.075 m tris(hydroxymethyl)aminomethane-phosphoric acid buffer (pH 7.3), the oxidation of NADH(2) was stimulated and succinoxidase was inhibited by high salt concentrations.

Alcohol Oxidoreductases↗
PubMed1965

RHYTHMIC RESPONSE OF SERRATIA MARCESCENS TO ELEVATED TEMPERATURE.

Dimmick, Robert L. (University of California, Berkeley). Rhythmic response of Serratia marcescens to elevated temperature. J. Bacteriol. 89:791-798. 1965.-Populations of Serratia marcescens of varied ages and pretreatments, which had been grown in a chemically defined medium, were subjected to thermal stress at 50 to 56 C. The numbers of survivors were plotted vs. time to form survivor curves, and the curves were assembled to form three-dimensional models. The manner in which survivors varied as a function of age and time of heating was variable and often rhythmic. Different three-dimensional patterns were found when different inoculum for the test culture was used. Apparently some "dead" cells again produced colonies after extended heating periods (recuperation); this tendency varied with the age of the culture. Diminutive colony forms, which produced normal colonies upon transfer, appeared and disappeared during heating; this tendency fluctuated with age. It is suggested that survivor curves represent a distribution of resistant forms within the population, and that this distribution varies in a manner best described in terms of servomechanistic response within each cell and within a given culture. Difficulties of attempting to relate changes in specific molecular species to subsequent whole-cell responses are discussed.

Hot Temperature↗
PubMed1965

High Susceptibility of Strain A Mice to Endotoxin and Endotoxin-Red Blood Cell Mixtures.

Heppner, Gloria (University of California, Berkeley), and David W. Weiss. High susceptibility of strain A mice to endotoxin and endotoxin-red blood cell mixtures. J. Bacteriol. 90:696-703. 1965.-Strain A mice were shown to be considerably more susceptible to lethal effects of endotoxin lipopolysaccharide (LPS) than mice of several other strains. Complexes of sublethal quantities of LPS and sheep red blood cells were synergistically toxic for strain A mice. Separate administration of sheep red blood cells and heat-killed salmonellae, in either order and as long as 24 hr apart, also proved to be synergistically lethal for strain A mice, but not for R(III) animals studied comparatively. Sheep red blood cell lysates possessed the ability of the intact cells in forming lethal combinations for strain A mice with killed salmonellae. Strain A red blood cell-killed salmonellae complexes were also lethal for strain A mice, but less so then complexes made with sheep red blood cells. A x R(III) F(1) hybrid animals showed the same resistance characteristics as the resistant R(III) parental strain. Possible explanations for these findings are suggested, and their relevance to an immunological mode of action of endotoxin lethality is discussed.

Journal Article↗
PubMed1965

Lifetime of bacterial messenger ribonucleic acid.

Moses, V. (University of California, Berkeley), and M. Calvin. Lifetime of bacterial messenger ribonucleic acid. J. Bacteriol. 90:1205-1217. 1965.-When cells from a stationary culture of Escherichia coli were placed in fresh medium containing inducer for beta-galactosidase, growth, as represented by increase in turbidity and by total protein synthesis, started within 30 sec. By contrast, beta-galactosidase synthesis was greatly delayed compared with induction during exponential growth. Two other inducible enzymes (d-serine deaminase and l-tryptophanase) and one repressible enzyme (alkaline phosphatase) showed similar lags. The lags were not due to catabolite repression. They could not be reduced by pretreatment of the culture with inducer, or by supplementing the fresh medium with amino acids or nucleotides. The lag was also demonstrated by an i(-) mutant constitutive for beta-galactosidase synthesis. An inhibitor of ribonucleic acid (RNA) synthesis, 6-azauracil, preferentially inhibited beta-galactosidase synthesis compared with growth in both inducible and constitutive strains. Puromycin, an inhibitor of protein synthesis, acted as an inhibitor at additional sites during the induction of beta-galactosidase synthesis. No inhibition of the reactions proceeding during the first 20 sec of induction was observed, but puromycin seemed to prevent the accumulation of messenger RNA during the period between 20 sec and the first appearance of enzyme activity after 3 min. It is suggested that these observations, together with many reports in the literature that inducible enzyme synthesis is more sensitive than total growth to some inhibitors and adverse growth conditions, can be explained by supposing that messenger RNA for normally inducible enzymes is biologically more labile than that for some normally constitutive proteins. The possible implications of this hypothesis for the achievement of cell differentiation by genetic regulation of enzyme synthesis are briefly discussed.

Chemical Phenomena↗
PubMed1965

Decomposition of poly-beta-hydroxybutyrate by pseudomonads.

Delafield, F. P. (University of California, Berkeley), M. Doudoroff, N. J. Palleroni, C. J. Lusty, and R. Contopoulos. Decomposition of poly-beta-hydroxybutyrate by pseudomonads. J. Bacteriol. 90:1455-1466. 1965.-A number of aerobic pseudomonads capable of using poly-beta-hydroxybutyrate as sole source of carbon have been partially characterized. One was selected for special study and described as a new species, Pseudomonas lemoignei Delafield. This bacterium constitutively produces extracellular digestive enzymes that hydrolyze the polymer to a mixture of d-beta-hydroxybutyrate and the dimeric ester of this acid, as well as an intracellular "dimer hydrolase" which hydrolyzes the dimeric ester. The exoenzymes are excreted during growth, but mainly at its cessation. Metabolism of beta-hydroxybutyrate largely suppresses enzyme excretion and causes a disappearance of excreted enzyme.

Hydroxybutyrates↗
PubMed1966

Delayed dermal hypersensitivity in mice to spherule and mycelial extracts of Coccidioides immitis.

Kong, Yi-chi M. (University of California, Berkeley), D. C. Savage, and Leighton N. L. Kong. Delayed dermal hypersensitivity in mice to spherule and mycelial extracts of Coccidioides immitis. J. Bacteriol. 91:876-883. 1966.-A delayed hypersensitivity reaction to spherule and mycelial extracts of Coccidioides immitis was elicited in the footpads of mice vaccinated with killed spherules. Emulsification of the spherules with Freund's adjuvants was unnecessary, but a high concentration of antigen was required to elicit the reaction. Injection of the extracts produced, initially, a swelling which subsided within 4 hr, and then induration, which began at 6 to 8 hr and reached a maximum at 24 hr. The time course of the reaction corresponded to that of the tuberculin reaction in BCG-vaccinated mice. The histological response to coccidioidal extracts was characterized by the early infiltration of both polymorphonuclear and mononuclear cells, and the subsequent predominance of mononuclear cells at 24 to 48 hr. By 72 hr, the mononuclear cells comprised >90% of the cellular infiltrate. Animals infected intranasally with arthrospores (1 to 5 ld(50)) reacted negatively before and during the crisis period; thereafter (by 28 to 31 days after infection), up to 50% of the survivors showed a delayed reaction.

Animals↗
PubMed1966

Synthesis of the enzymes of the mandelate pathway by Pseudomonas putida. I. Synthesis of enzymes by the wild type.

Hegeman, G. D. (University of California, Berkeley). Synthesis of the enzymes of the mandelate pathway by Pseudomonas putida. I. Synthesis of enzymes by the wild type. J. Bacteriol. 91:1140-1154. 1966.-The control of synthesis of the five enzymes responsible for the conversion of d(-)-mandelate to benzoate by Pseudomonas putida was investigated. The first three compounds occurring in the pathway, d(-)-mandelate, l(+)-mandelate, and benzoylformate, are equipotent inducers of all five enzymes. A nonmetabolizable inducer, phenoxyacetate, also induces synthesis of these enzymes; but, unlike the metabolizable inducer-substrates, it does not elicit synthesis of enzymes that mediate steps in the pathway beyond benzoate. Under conditions of semigratuity, dl-mandelate elicits immediate synthesis at a steady rate of the first two enzymes of the pathway, but two enzymes which act below the level of benzoate are synthesized only after a considerable lag. Succinate and asparagine do not significantly repress the synthesis of the enzymes responsible for mandelate oxidation.

Asparagine↗
PubMed1966

Synthesis of the enzymes of the mandelate pathway by Pseudomonas putida. II. Isolation and properties of blocked mutants.

Hegeman, G. D. (University of California, Berkeley). Synthesis of the enzymes of the mandelate pathway by Pseudomonas putida. II. Isolation and properties of blocked mutants. J. Bacteriol. 91:1155-1160. 1966.-Mutants of Pseudomonas putida blocked in early reactions of the pathway for oxidation of d-mandelate were isolated and partially characterized. The specific genetic lesions in these mutants made normal inducer-metabolites of the pathway nonmetabolizable. Under the conditions of gratuitous enzyme synthesis so obtained, it could be shown that the d and l isomers of mandelate are equipotent inducers, and that the synthesis of the first five enzymes of the mandelate pathway is coordinate. Further experiments with the blocked mutants showed that benzoylformate, the third intermediate of the pathway, acts as an inducer without prior conversion to mandelate, and that there is no inducible, concentrating permease for mandelate.

Carboxy-Lyases↗
PubMed1966

Synthesis of the enzymes of the mandelate pathway by Pseudomonas putida. 3. Isolation and properties of constitutive mutants.

Hegeman, G. D. (University of California, Berkeley). Synthesis of the enzymes of the mandelate pathway by Pseudomonas putida. III. Isolation and properties of constitutive mutants. J. Bacteriol. 91:1161-1167. 1966.-Mutants of Pseudomonas putida constitutive for the synthesis of l(+)-mandelate dehydrogenase were obtained after mandelate- or benzoylformate-limited growth in a chemostat. When grown in media noninducing for the wild type, the mutants are capable of coordinate, constitutive synthesis of the first five enzymes of the mandelate pathway. Later enzymes of the pathway that were examined are normally repressed. The constitutive mutants have two other noteworthy properties: they are superinducible by some compounds which induce the mandelate group enzymes in the wild type, or as a result of exhaustion of the carbon and energy source of the medium in which they are grown; and they exhibit a decreased specificity of induction, being inducible by a wide range of compounds devoid of inductive function for the wild type. These results, together with other evidence indicating that the five mandelate group enzymes comprise a regulatory unit, are discussed and evaluated in the context of the general problem of the regulation of complex dissimilatory pathways.

Carboxy-Lyases↗
PubMed1966

Effect of 3 percent hydrogen peroxide on the viability of Serratia marcescens.

Campbell, Jack E. (University of California, Berkeley), and R. L. Dimmick. Effect of 3% hydrogen peroxide on the viability of Serratia marcescens. J. Bacteriol. 91:925-929. 1966.-Populations of Serratia marcescens were exposed to 3% H(2)O(2) at temperatures from 0 to 20 C. The reaction appeared to follow an Arrhenius plot, but variable numbers of diminutive colonies were found after cell numbers started to decrease. Colony numbers varied on different sampling media and increased when additional incubation was imposed. The overall reaction was sensitive to age of culture, and growth capabilities of treated samples varied with time of treatment, especially during times when no loss of viability was noted. Catalase activity per cell did not correlate with changes in sensitivity; iron added to growth medium increased catalase activity and decreased sensitivity, but not in the same manner. Although the fundamental reaction is presumably molecular in nature, present methods of viability assay measure more than single events and are not suitable for these studies.

Catalase↗
PubMed1966

Action of phyenethyl alcohol on the synthesis of macromolecules in Escherichia coli.

Prevost, C. (University of California, Berkeley), and V. Moses. Action of phenethyl alcohol on the synthesis of macromolecules in Escherichia coli. J. Bacteriol. 91:1446-1452. 1966.-A kinetic study of the effects of various concentrations of phenethyl alcohol on the synthesis of ribonucleic acid (RNA), deoxyribonucleic acid (DNA), protein, and beta-galactosidase in Escherichia coli has confirmed that RNA synthesis, rather than DNA synthesis, is first and most affected by phenethyl alcohol. The presence of inducer did not protect beta-galactosidase synthesis from inhibition by phenethyl alcohol. Little preferential inhibition of beta-galactosidase synthesis was observed; this is in contrast to the severe catabolite repression which results from partial inhibition of total protein synthesis caused by chloramphenicol or starvation for a required amino acid. We found no evidence that messenger RNA synthesis was inhibited to a greater extent than total RNA synthesis.

Bacterial Proteins↗
PubMed1966

Growth and survival of Mycoplasma neurolyticum in liquid media.

Hottle, G. A. (Naval Biological Laboratory, University of California, Berkeley), and D. N. Wright. Growth and survival of Mycoplasma neurolyticum in liquid media. J. Bacteriol. 91:1834-1839. 1966.-Maximal growth of Mycoplasma neurolyticum (between 10(8) and 10(9) colony-forming units per ml) was obtained after 3 days of incubation at 36 C in broth media containing 10% agamma horse serum. When whole horse serum was used in the medium, a complement-mediated inhibition was observed. This inhibition could only be detected when growth was followed by daily plate counts. Maximal growth was delayed for about 24 hr by the horse serum, and the inhibition was spontaneously reversed at the temperature of incubation. Penicillin G was also found to have a temporary inhibitory effect. This was detected with as little as 40 units per ml. Maximal growth was delayed until the 6th day of incubation, when 200 units per ml was present, and until the 16th day, when 1,000 units per ml was present. The survival of M. neurolyticum at undetectable levels in cultures during the incubation period presented an "eclipse" phenomenon which has not been explained. The recrudescence of growth in such cultures late in the incubation period illustrates the events which may occur when mycoplasmas are isolated from clinical material by prolonged incubation in the presence of inhibitors. Survival data showed that M. neurolyticum had greatest stability at pH 8.0, with reduced viability at pH 9.0, 7.0, 10.0, and 6.0, in that order The data on growth and stability suggest a close relationship between the species. of Mycoplasma studied and bacteria.

Anti-Bacterial Agents↗
PubMed1966

Differential inhibitory effects of actinomycin D among strains of poliovirus.

Schaffer, Frederick L. (University of California, Berkeley), and Marjorie Gordon. Differential inhibitory effects of actinomycin D among strains of poliovirus. J. Bacteriol. 91:2309-2316. 1966.-Actinomycin D exerted a differential effect on the ability of strains of poliovirus to replicate in HeLa cells. LSc-2ab was studied as an example of a strain markedly inhibited by actinomycin; MEF(1) served as a control strain with minimal inhibition. The effect was noted at an actinomycin concentration of 0.1 mug/ml, but 2.5 mug/ml was used for most studies. Variability in the effect was attributed, in part, to physiological factors. Actinomycin was effective when present during the first 2 hr of LSc infection, but had little effect if present at later times. It did not block adsorption or initiation of ecilpse. It did block synthesis of ribonucleic acid in LSc-infected cells. Several possible modes of action are discussed, the most attractive being that actinomycin blocks synthesis of some cell component, the concentration of which is more critical for replication of some poliovirus strains than others.

Adsorption↗
PubMed1966

Unsaturated fatty acid mutants of Saccharomyces cerevisiae.

Resnick, Michael A. (University of California, Berkeley), and Robert K. Mortimer. Unsaturated fatty acid mutants of Saccharomyces cerevisiae. J. Bacteriol. 92:597-600. 1966.-The wild type of the yeast Saccharomyces cerevisiae does not require fatty acids or sterols for growth. Two types of lipid nutritional mutants have been induced in this organism. One of these classes of mutants requires an unsaturated fatty acid and is associated with a locus on chromosome VII. The other class of mutants needs either an unsaturated fatty acid or ergosterol for growth. Experiments involving identification and characterization of these mutants are presented.

Chromosome Mapping↗
PubMed1966

Production in FL cells of infectious and potentially infectious reovirus.

Spendlove, Rex S. (California State Department of Public Health, Berkeley), Edwin H. Lennette, Charles O. Knight, and Jean N. Chin. Production in FL cells of infectious and potentially infectious reovirus. J. Bacteriol. 92:1036-1040. 1966.-A comparative study was made of the development in, and release from, FL cells of infectious and potentially infectious (chymotrypsin-activatable) reovirus (Lang strain). The latent period was shorter, the rate of synthesis was more rapid, and the total yield was more than 10-fold greater in potentially infectious virus as compared with infectious virus. Almost all of the potentially infectious virus, but only approximately one-third of the infectious virus, was released from the infected cells.

Chymotrypsin↗
PubMed1966

Multiplicity reactivation of reovirus particles after exposure to ultraviolet light.

McClain, Mary E. (California State Department of Public Health, Berkeley), and Rex S. Spendlove. Multiplicity reactivation of reovirus particles after exposure to ultraviolet light. J. Bacteriol. 92:1422-1429. 1966.-Exposure of reovirus suspensions to moderate doses of ultraviolet light results in essentially exponential inactivation of infectivity to survivals of 10(-2) to 10(-3). With suspensions of sufficiently high particle concentration, larger doses of ultraviolet light (6 to 12 min) are associated with multiplicity reactivation (MR) which is demonstrable both by immunofluorescent-cell count and by plaque assay in FL human amnion cells. Similar effects are produced by photodynamic inactivation in the presence of proflavine, but not by thermal inactivation at 50 C. All three reovirus types exhibit MR under appropriate conditions, and all three interact in mixed ultraviolet suspensions with high efficiency. Progeny from FL cells infected under conditions of MR were as infectious as those of unirradiated inocula, with yields per cell ranging from 10(4) to 4 x 10(4) infective units.

Amnion↗
PubMed1985

Evaluation of Mycotrim-GU for isolation of Mycoplasma species and Ureaplasma urealyticum.

The Mycotrim-GU (Hana Biologics, Berkeley, Calif.) biphasic culture system and a conventional system were compared for their ability to detect Ureaplasma urealyticum and Mycoplasma species in 100 clinical specimens. Both systems detected 18 Mycoplasma spp. isolates. The average colony detection time was 1.9 days with the Mycotrim-GU and 2.3 days with the conventional system. The Mycotrim-GU agar detected all 33 U. urealyticum isolates recovered in the study, and the conventional agar detected 31. In addition to the U. urealyticum isolates recovered from the agar, there were several specimens that, although they did not grow colonies on the agar, gave an alkaline broth change. Of these specimens, two were found with the conventional system and seven were found with the Mycotrim-GU. The average detection time of U. urealyticum colonies was 2.0 days for the conventional agar and 1.7 days for the Mycotrim-GU. The Mycotrim-GU offers several advantages over the conventional system: it is commercially available, consists of a one-flask system which is ready to use, has a significantly longer shelf life, and is cost competitive. This study showed the Mycotrim-GU to be an effective system for detecting the genital mycoplasmas.

Culture Media↗
PubMed1992

Association of an important Neisseria species, Neisseria elongata subsp. nitroreducens, with bacteremia, endocarditis, and osteomyelitis.

We retrospectively analyzed epidemiologic information associated with 22 cultures of Neisseria elongata subsp. nitroreducens (formerly CDC group M-6) submitted to the Microbial Diseases Laboratory, California Department of Health Services, Berkeley, over a 16-year period. The most common illnesses noted with this bacterium were endocarditis, bacteremia, and osteomyelitis. Risk factors associated with N. elongata subsp. nitroreducens infection included dental manipulations and/or a previous history of endocarditis, valve damage, or rheumatic heart disease.

Adult↗