(Symposium on Bacterial Spores: Paper II). Genetics of Sporulation in <i>Bacillus subtilis</i> Marburg

Ionesco, H; Michel, Janine F.; Cami, B.; Schaeffer, Pierre

doi:10.1111/j.1365-2672.1970.tb05230.x

Cited by 79 publications

(10 citation statements)

References 19 publications

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“…Wild-type B. subtilis strain NCTC 3610 (ATCC 6051), a Marburg strain, was used for all experiments except where otherwise indicated. The asporogenous mutants (6) were kindly provided by P. Schaeffer.…”

Section: Methodsmentioning

confidence: 99%

An Immunological Assay for the Sigma Subunit of RNA Polymerase in Extracts of Vegetative and Sporulating Bacillus subtilis

Tjian

Losick

1974

Proc. Natl. Acad. Sci. U.S.A.

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The activity of the a subunit of Bacillus subtilis RNA polymerase decreases markedly during the first hours of sporulation [T. The onset of sporulation by Bacillus subtilis is associated with a change in the template specificity of RNA polymerase (1). Enzyme isolated from sporulating bacteria is unable to transcribe certain phage DNA templates as actively in vitro as RNA polymerase from vegetative B. subtilis. However, RNA polymerase in certain mutants blocked at an early stage of spore formation retains, throughout stationaryphase, the template recognition properties characteristic of enzyme from vegetative bacteria (2, 3). The change in template specificity is apparently caused by a marked decrease in the activity of the a subunit of RNA polymerase rather than an alteration of the core subunits, ,B, f', and a (4, 5).However, it has previously not been possible to determine whether sporulating bacteria actually lack a polypeptide or whether the a polypeptide is present but its activity inhibited during spore formation. To distinguish between these alternatives, we report an immunological assay that provides a direct test for the presence of the a polypeptide in extracts of vegetative and sporulating B. subtilis. METHODSCells. Wild-type B. subtilis strain NCTC 3610 (ATCC 6051), a Marburg strain, was used for all experiments except where otherwise indicated. The asporogenous mutants (6) were kindly provided by P. Schaeffer.Media and Sporulation. Growth and sporulation of B. subtilis 3610 was in 121B medium (7) and sporulating cells were harvested 4.5 hr after the end of a logarithmic growth (T4.5) unless otherwise noted. For radioactive labeling of cells, the radioactive precursor was added during early logarithmic growth. Strain SMY and the asporogenous mutants were grown (8) in Difco sporulation medium (DSAI); cells were harvested either at mid-logarithmic phase or allowed to enter stationary phase by continued growth in DS'M or by resuspension of logarithmically growing cells in Sterlini-MNandelstam (SM) medium (9). In DSM and SAM media, sporulating or stationary-phase cells were harvested either 3 hr after the end of logarithmic growth (T3) or 3 hr after resuspending in SM medium (T3). After harvesting, cells were washed with buffer G (0.05 M Tris-HCl, pH 7.5, 0.01 MI MNlgCI2, 0.1 mMNi ethylenediaminetetraacetate, 0.1 mMI dithiothreitol, 10% v/v glycerol) containing 1.0 AM KC1 (10) and 5%lphenyl-methylsulfonyl fluoride solution (6 mg/ml of 95% ethanol) to remove extracellular proteases and then rapidly frozen.Cells Extracts Were Prepared from about 2 g of cells by disruption in a Braun homogenizer and high speed centrifugation as previously described (5)

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Section: Methodsmentioning

confidence: 99%

An Immunological Assay for the Sigma Subunit of RNA Polymerase in Extracts of Vegetative and Sporulating Bacillus subtilis

Tjian

Losick

1974

Proc. Natl. Acad. Sci. U.S.A.

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“…For peroxide resistance experiments involving E. coli, strain CH734 was used. For probing of B genes by PCR, the following bacterial strains were used: Staphylococcus aureus Newman (16), Listeria monocytogenes 104035 (45), and B. subtilis Marburg 168 (34). Luria-Bertani broth (48) or tryptone agar (137 mM NaCl, 1% tryptone [wt/vol], 0.1% yeast extract [wt/vol], and 1.4% agar) were used to culture E. coli.…”

Section: Methodsmentioning

confidence: 99%

Aerotolerance and Peroxide Resistance in Peroxidase and PerR Mutants of Streptococcus pyogenes

2000

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Survival in aerobic conditions is critical to the pathogenicity of many bacteria. To investigate the means of aerotolerance and resistance to oxidative stress in the catalase-negative organism Streptococcus pyogenes, we used a genomics-based approach to identify and inactivate homologues of two peroxidase genes, encoding alkyl hydroperoxidase (ahpC) and glutathione peroxidase (gpoA). Single and double mutants survived as well as the wild type under aerobic conditions. However, they were more susceptible than the wild type to growth suppression by paraquat and cumene hydroperoxide. In addition, we show that S. pyogenes demonstrates an inducible peroxide resistance response when treated with sublethal doses of peroxide. This resistance response was intact in ahpC and gpoA mutants but not in mutants lacking PerR, a repressor of several genes including ahpC and catalase (katA) in Bacillus subtilis. Because our data indicate that these peroxidase genes are not essential for aerotolerance or induced resistance to peroxide stress in S. pyogenes, genes for a novel mechanism of managing peroxide stress may be regulated by PerR in streptococci.

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“…Non-sporulating B. subtilis 11T (DspoIIIC11) [20] were grown on nitrocellulose filters (Millipore) placed on Luria broth (LB) agar plates for 18 h at 378C. Filters were removed from agar plates and placed under one of the three jets for treatment in He atmosphere.…”

Section: Scanning Electron Microscopymentioning

confidence: 99%

Photons and particles emitted from cold atmospheric-pressure plasma inactivate bacteria and biomolecules independently and synergistically

Lackmann

Schneider

Edengeiser

et al. 2013

J. R. Soc. Interface.

156

133

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Cold atmospheric-pressure plasmas are currently in use in medicine as surgical tools and are being evaluated for new applications, including wound treatment and cosmetic care. The disinfecting properties of plasmas are of particular interest, given the threat of antibiotic resistance to modern medicine. Plasma effluents comprise (V)UV photons and various reactive particles, such as accelerated ions and radicals, that modify biomolecules; however, a full understanding of the molecular mechanisms that underlie plasma-based disinfection has been lacking. Here, we investigate the antibacterial mechanisms of plasma, including the separate, additive and synergistic effects of plasma-generated (V)UV photons and particles at the cellular and molecular levels. Using scanning electron microscopy, we show that plasma-emitted particles cause physical damage to the cell envelope, whereas UV radiation does not. The lethal effects of the plasma effluent exceed the zone of physical damage. We demonstrate that both plasma-generated particles and (V)UV photons modify DNA nucleobases. The particles also induce breaks in the DNA backbone. The plasma effluent, and particularly the plasma-generated particles, also rapidly inactivate proteins in the cellular milieu. Thus, in addition to physical damage to the cellular envelope, modifications to DNA and proteins contribute to the bactericidal properties of cold atmospheric-pressure plasma.

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(Symposium on Bacterial Spores: Paper II). Genetics of Sporulation in Bacillus subtilis Marburg

Cited by 79 publications

References 19 publications

An Immunological Assay for the Sigma Subunit of RNA Polymerase in Extracts of Vegetative and Sporulating Bacillus subtilis

An Immunological Assay for the Sigma Subunit of RNA Polymerase in Extracts of Vegetative and Sporulating Bacillus subtilis

Aerotolerance and Peroxide Resistance in Peroxidase and PerR Mutants of Streptococcus pyogenes

Photons and particles emitted from cold atmospheric-pressure plasma inactivate bacteria and biomolecules independently and synergistically

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