The genome of Bacillus subtilis phage SP10: a comparative analysis with phage SPO1.

A nucleotide sequence of the whole genome of Bacillus subtilis phage SP10 was determined. It was composed of 143,986 bp with 236 putative open reading frames (ORFs). Sixty-five of 236 predicted ORFs showed high similarity to that of SPO1, and the genome organizations of the two phages were similar to each other. SP10 belongs to the Myoviridae family, for which the well-studied phage SPO1 is the representative phage. Hence, we compared SP10 to SPO1. The SP10 genome DNA showed different sensitivity to restriction enzymes than SPO1, due to differences in base modification. According to transcriptional analysis, the gene expression of regulatory network of SP10 was similar to SPO1. It was observed that RNA polymerase containing sigma-A was inactive in directing the host genes but active in directing the phage genes. It appeared that the association of sigma-A with the core enzyme complex of RNA polymerase was strengthened during development.