Characterization of csgA, a new member of the forespore-expressed sigmaG-regulon from Bacillus subtilis.

A new locus, csgA, has been identified in a search for developmental genes transcribed by E sigmaG in Bacillus subtilis. csgA has the potential to encode three small proteins, CsgAA, CsgAB and CsgAC. The latter two would be encoded by overlapping ORFs. csgA is expressed in the spore chamber of the differentiating cell and is under the control of sigmaG and the transcriptional regulatory protein SpoVT. Mutation of csgA did not affect spore formation but produced a subtle defect in the ability of the germinating spore to resume vegetative growth.