THE POLYVALENT STAPHYLOCOCCAL PHAGE PHI-812 - ITS HOST-RANGE MUTANTS AND RELATED PHAGES

Ninety-five percent of 782 culture collection strains, as well as hosp ital strains of Staphylococcus aureus subsp. aureus of different prove nance and 43% of 89 culture collection strains oi different coagulase- negative species of the genus Staphylococcus, were found to be sensiti ve to the polyvalent phage phi 812 or to at least one of its host-rang e mutants or to the polyvalent phages SK311, phi 131 and U16. Thus sen sitivity to the polyvalent staphylococcal phages seems to be one of th e common features of S. aureus subsp. aureus strains. The adsorption k inetics and one-step growth characteristics of the phages phi 812 and SK311 were estimated. Restriction genomic maps of the phages phi 812 ( 146.5 kb) and SK311 (141.1 kb) were constructed by use of the restrict ion endonucleases Avail, PstI, KpnI, SacI, SmaI, and XhoI. The host-ra nge mutations of the phage phi 812 were localized on this map. Compari son of restriction patterns of the phages phi 812 and SK311 with those of the polyvalent phages U16 and (phi 131 suggests that all these pha ges are closely related. Their genomes differ from each other mostly b y some deletions, insertions (1-3 kb), cr inversions. Evidence was giv en that the phage phi 812 together with SK311, phi 131, and U16 belong s in the phage species Twort, the description of which is substantiall y supplemented with the data on the phage phi 812 reported in this pap er. (C) 1998 Academic Press.