Restriction and modification in Bacillus subtilis: DNA methylation potential of the related bacteriophages Z, SPR, SP beta, phi 3T, and rho 11.

The DNA methylation capacity and some other properties of the related temperate Bacillus subtilis phages Z, SPR, SP beta, phi 3T, and rho 11 are compared. With phage mutants affected in their methylation potential, we show that phage-coded methyltransferase genes are interchangeable among the phages studied. DNA/DNA hybridization experiments indicate that phage methyltransferase genes are structurally related, whereas no such relationship is observed to a bacterial gene, specifying a methyltransferase with the same specificity.