The global expression profile of Bacillus subtilis to the toxic carbonyls methylglyoxal (MG) and formaldehyde (FA)

ABSTRACT: Abstract of associated menuscript; Quinones and alpha,beta-unsaturated carbonyls are naturally occurring electrophiles that target cysteine residues via thiol-(S)-alkylation. We analyzed the global expression profile of Bacillus subtilis to the toxic carbonyls methylglyoxal (MG) and formaldehyde (FA). Both carbonyl compounds cause a stress response characteristic for thiol-reactive electrophiles as revealed by the induction of the Spx, CtsR, CymR, PerR, ArsR, CzrA, CsoR and SigmaD regulons. MG and FA triggered also a SOS response which indicates DNA damage. Protection against FA is mediated by both the hxlAB operon, encoding the ribulose monophosphate pathway for FA fixation, and a thiol-dependent formaldehyde dehydrogenase (AdhA) and DJ-1/PfpI-family cysteine proteinase (YraA). The adhA-yraA operon and the yraC gene, encoding gamma-carboxymuconolactone decarboxylase, are positively regulated by the MerR-family regulator, YraB(AdhR). AdhR binds specifically to its target promoters which contain a 7-4-7 inverted repeat (CTTAAAG-N4-CTTTAAG) between the -35 and -10 elements. Activation of adhA-yraA transcription by AdhR requires the conserved Cys52 residue in vivo. We speculate that AdhR is redox-regulated via thiol-(S)-alkylation by aldehydes and that AdhA and YraA are specifically involved in reduction of aldehydes and degradation or repair of damaged thiol-containing proteins, respectively. WT (-FA) vs. WT (+ 1 mM FA), WT (-MG) vs. WT (+ 2.8 mM MG), WT (-MG) vs. WT (+ 5.6 mM MG). Each experiement was conducted triplicates using three independent total RNA preparations. For all datasets used for final analysis, untreated samples were labeled with Cy3 and treated samples with Cy5.

ORGANISM(S): Bacillus subtilis

SUBMITTER: John Helmann 

PROVIDER: E-GEOD-13925 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress