The bdbDC operon of Bacillus subtilis encodes thiol-disulfide oxidoreductases required for competence development

• Published in: The Journal of biological chemistry 2002-03, Vol.277 (9), p.6994-7001
• Main Authors: Meima, Rob, Eschevins, Caroline, Fillinger, Sabine, Bolhuis, Albert, Hamoen, Leendert W, Dorenbos, Ronald, Quax, Wim J, van Dijl, Jan Maarten, Provvedi, Roberta, Chen, Ines, Dubnau, David, Bron, Sierd
• Format: Article
• Language: English
• Subjects: Alkaline Phosphatase - metabolism; Amino Acid Sequence; Bacillus subtilis; Bacillus subtilis - enzymology; Bacillus subtilis - genetics; bdbC gene; bdbD gene; Biochemistry; Biochemistry, Molecular Biology; Blotting, Western; Cyclin-Dependent Kinases - metabolism; Dimerization; Disulfides; DNA - metabolism; Electrophoresis, Polyacrylamide Gel; Escherichia coli; Escherichia coli - enzymology; Escherichia coli - metabolism; Escherichia coli Proteins; Genetic Complementation Test; Life Sciences; Mitomycin - pharmacology; Models, Genetic; Molecular Sequence Data; Mutation; Operon; Plasmids - metabolism; Protein Binding; Protein Disulfide Reductase (Glutathione) - chemistry; Protein Disulfide Reductase (Glutathione) - genetics; Protein Disulfide Reductase (Glutathione) - physiology; Recombination, Genetic; Sequence Homology, Amino Acid; Time Factors; Transcription Factors - metabolism; Transcription, Genetic; Transformation, Genetic
• ISSN: 0021-9258; 1083-351X
• DOI: 10.1074/jbc.M111380200

The development of genetic competence in the Gram-positive eubacterium Bacillus subtilis is a complex postexponential process. Here we describe a new bicistronic operon, bdbDC, required for competence development, which was identified by the B. subtilis Systematic Gene Function Analysis program. Inactivation of either the bdbC or bdbD genes of this operon results in the loss of transformability without affecting recombination or the synthesis of ComK, the competence transcription factor. BdbC and BdbD are orthologs of enzymes known to be involved in extracytoplasmic disulfide bond formation. Consistent with this, BdbC and BdbD are needed for the secretion of the Escherichia coli disulfide bond-containing alkaline phosphatase, PhoA, by B. subtilis. Similarly, the amount of the disulfide bond-containing competence protein ComGC is severely reduced in bdbC or bdbD mutants. In contrast, the amounts of the competence proteins ComGA and ComEA remain unaffected by bdbDC mutations. Taken together, these observations imply that in the absence of either BdbC or BdbD, ComGC is unstable and that BdbC and BdbD catalyze the formation of disulfide bonds that are essential for the DNA binding and uptake machinery.