Nucleotide sequence and gene organization of the gerK spore germination locus of Bacillus subtilis 168

The nucleotide sequence of the whole gerK spore germination locus of Bacillus subtilis has been determined by sequencing the remaining first and third genes of the locus. The gerK locus contained three open reading frames capable of encoding polypeptides of 546, 407 and 373 amino acids. Each predicted gene product had homologues in the gerA and gerB operon, but the gene order was different from that of gerA and gerB, Sequences regarded as - 10 and -35 promoter sequences for the sigma-G type RNA polymerase was found upstream of the first gene suggesting that the gerK also is an operon expressed specifically in the forespore during sporulation. All three genes were suggested to be essential for spore germination in response to glucose.