Two Different Panton-Valentine Leukocidin Phage Lineages Predominate in Japan

Abstract

We determined the entire nucleotide sequence of Sa2958-carrying Panton-Valentine leukocidin (PVL) gene, which was lysogenized in a sequence type 5 staphylococcal cassette chromosome mec (SCCmec) type II strain of methicillin-resistant Staphylococcus aureus (MRSA). Based on the nucleotide sequences of PVL phages, we developed PCRs to discriminate among five PVL phages, with a preliminary classification into two morphological groups (elongated-head type and icosahedral-head type) with four PCRs, including two PCRs for identifying the gene lineage between lukS-PV and the tail gene. The phages were then classified into five types by four PCRs identifying each phage-specific structure. With these PCRs, we examined the PVL phage types of 67 MRSA strains isolated in Japan from 1979 through 1985 and since 2000 and found that two morphologically distinct phages were predominant in Japan. The icosahedral-head-type phage, represented by the 108PVL type, was identified for 39 of 53 strains isolated from 1979 through 1985. Of 26 other Japanese isolates, 25 belonged either definitively or presumably to elongated-head types as follows: 3 belonged to the Sa2958 type; 8 were determined to belong to an elongated-head type, but a determination of greater specificity was not made; and 14 belonged to a Sa2958-like phage of unknown type. We induced prophages by treatment with mitomycin C from six strains of the Sa2958 type or of Sa2958-like unknown-type phages; five of six strains carried intact PVL-carrying phages, which can infect other S. aureus strains and might generate novel PVL-positive strains of S. aureus. That various SCCmec elements were carried by different strains of the same phage type suggests that S. aureus strains might independently acquire PVL phages before they acquire various SCCmec elements.

Molecular tracing of the emergence, adaptation, and transmission of hospital-associated methicillin-resistant Staphylococcus aureus

“…1). The PVL toxin is encoded by temperate phage, which can be differentiated into distinct morphological groups on the basis of their elongated-or icosahedral-head types (31). Sequence analysis of the small and large terminase subunits of the PVL phage revealed that three of four SWP clone isolates contained the elongated-head phage type, whereas the remaining SWP isolate and the phage type 80/81 isolates had the icosahedral-head phage type.…”

Transcription of the phage-encoded Panton–Valentine leukocidin of Staphylococcus aureus is dependent on the phage life-cycle and on the host background

“…Interestingly, other PVL-carrying phages (e.g. wSa2985PVL and w108PVL) encode repressors which exhibit the typical lambdoid repressor structure (Ma et al, 2008).…”

Panton-Valentine Leukocidin (PVL)-Positive Health Care-Associated Methicillin-Resistant Staphylococcus aureus Isolates Are Associated with Skin and Soft Tissue Infections and Colonized Mainly by Infective PVL-Encoding Bacteriophages

“…The diffusion of PVL genes to different MRSA lineages is mediated by PVL bacteriophages (also called phages). Seven PVL phages (⌽108PVL, ⌽PVL, ⌽SLT, ⌽Sa2958, ⌽Sa2MW, ⌽Sa2usa, and ⌽7247PVL) have been described in detail (13)(14)(15)(16)(17)(18). ⌽PVL and ⌽108PVL were observed to be defective phages because they carry truncated genes related to tail formation (13,18).…”

“…⌽PVL and ⌽108PVL were observed to be defective phages because they carry truncated genes related to tail formation (13,18). ⌽SLT and ⌽Sa2958 have intact infectious ability, and the infective ⌽7247PVL phage can also be induced (15)(16)(17). Moreover, the integrase gene is conserved among the PVL-carrying phages, the attachment sites of which are present in various MRSA lineages.…”