Identification of a second region of the Spo0A response regulator of Bacillus subtilis required for transcription activation.

Deletion of the 10 C-terminal amino acids of the Bacillus subtilis response regulator Spo0A or valine substitution at D258 and L260 resulted in a sporulation-negative phenotype and loss of in vivo activation of the spoIIG and spoIIA operon promoters. Repression of the abrB promoter was not affected by the mutations. In combination with the previously characterized mutation (A257V), the results identify amino acids at positions 257, 258, and 260 as being required for transcription activation by Spo0A.