Contributions of Individual B-Dependent General Stress Genes to Oxidative Stress Resistance of Bacillus subtilis

Ernst-Moritz-Arndt Universität Institut für Mikrobiologie, Greifswald, Germany.
Journal of bacteriology (Impact Factor: 2.81). 05/2012; 194(14):3601-10. DOI: 10.1128/JB.00528-12
Source: PubMed


The general stress regulon of Bacillus subtilis comprises approximately 200 genes and is under the control of the alternative sigma factor σB. The activation of σB occurs in response to multiple physical stress stimuli as well as energy starvation conditions. The expression of the general
stress proteins provides growing and stationary nonsporulating vegetative cells with nonspecific and broad stress resistance.
A previous comprehensive phenotype screening analysis of 94 general stress gene mutants in response to severe growth-inhibiting
stress stimuli, including ethanol, NaCl, heat, and cold, indicated that secondary oxidative stress may be a common component
of severe physical stress. Here we tested the individual contributions of the same set of 94 mutants to the development of
resistance against exposure to the superoxide-generating agent paraquat and hydrogen peroxide (H2O2). In fact, 62 mutants displayed significantly decreased survival rates in response to paraquat and/or H2O2 stress compared to the wild type at a confidence level of an α value of ≤0.01. Thus, we were able to assign 47 general stress
genes to survival against superoxide, 6 genes to protection from H2O2 stress, and 9 genes to the survival against both. Furthermore, we show that a considerable overlap exists between the phenotype
clusters previously assumed to be involved in oxidative stress management and the actual group of oxidative-stress-sensitive
mutants. Our data provide information that many general stress proteins with still unknown functions are implicated in oxidative
stress resistance and further support the notion that different severe physical stress stimuli elicit a common secondary oxidative


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Article: Contributions of Individual B-Dependent General Stress Genes to Oxidative Stress Resistance of Bacillus subtilis

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    • "n important protein in correct functioning of the ribosomes ( Akanuma et al . , 2012 ) but the effect of knocking - out rpsU in B . subtilis on its stress resistance was not evaluated . Deletion of the genes encoding ribosomal pro - teins L31 and L25 in B . subtilis did result in phenotypes with increased stress resistance ( Höper et al . , 2005 ; Reder et al . , 2012 ) . Some recent proteome and transcriptome studies in L . monocy - togenes found differential expression of ribosomal proteins upon stress exposure ( Ivy et al . , 2012 ; Durack et al . , 2013 ; Melo et al . , 2013 ; Pleitner et al . , 2014 ) . Also , a role in cold adaptation and cold stress response of L . monocytogenes has been sugge"
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    • "In B. subtilis a secondary oxidative stress response is linked to the MgsR transcriptional regulator [87,88]. This σB dependent regulator seems to sense and integrate the secondary oxidative stress signal and controls a specific subregulon within the σB dependent general stress regulon. "
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    • "This hypothesis is supported by the results of a recent follow-up phenotype screening of the previously used set of 94 general stress gene mutants upon treatment with the superoxide-generating agent paraquat and hydrogen peroxide. In this study, 62 mutants (66%) displayed significantly decreased survival rates in response to oxidative stress (Reder et al., 2012). "
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