GENOME DIVERSITY IN TEMPERATE BACTERIOPHAGES OF OENOCOCCUS-OENI

The genome structure of six bacteriophages of Oenococcus oeni was comp ared. Two distinct groups with no apparent restriction site conservati on were defined. In members of the a group (fOgML34, fOg4029, fOg30 an d fOg218) a 7.5 kb region containing the origin of DNA packaging (cos) was highly conserved. Stretches of DNA heterogeneity could also be as signed to particular regions and were mostly evident in the right area of the genomes. fOg44 and fOgPSU1 (beta group) were indistinguishable in the left half of their genomes, including cos, but were markedly d issimilar in other regions. Strong labelling signals detected in cross -hybridizations involving members of different groups were confined to fragments centrally located in their physical maps. The attachment si te (attP) of fOg44 was assigned to this conserved region. It is sugges ted that recombination events at this location may have been important in generating the observed diversity of oenophage genomes.