Genome structure of the Lactobacillus temperate phage phi g1e: the whole genome sequence and the putative promoter/repressor system.

The complete genome sequence of a Lactobacillus temperate phage phi g1e was established. The double-stranded DNA is composed of 42,259 bp, and encodes for sixty-two possible open reading frames (ORF) as well as several potential regulatory sequences. Based on comparative analysis with other related proteins of the Lactobacillus and Lactococcus phages as well as the Escherichia coli phages (such as lambda), functions were putatively assigned to several phi g1e ORFs: cng and cpg (encoding for repressors), hel (helicase), ntp (NTPase), and several ORFs (e.g., minor capsid proteins). An about 1000-bp DNA region of phi g1e containing cpg and cng was inferred to function as a promoter/repressor system for the phi g1e lysogenic and lytic pathway.