Role of staphylococcal phage and SaPI integrase in intra- and interspecies SaPI transfer.
SaPIbov2 is a member of the SaPI family of staphylococcal pathogenicity islands and is very closely related to SaPIbov1. Typically, certain temperate phages can induce excision and replication of one or more of these islands and can package them into special small phage-like particles commensurate with their genome sizes (referred to as the excision-replication-packaging [ERP] cycle). We have studied the phage-SaPI interaction in some depth using SaPIbov2, with special reference to the role of its integrase. We demonstrate here that SaPIbov2 can be induced to replicate by different staphylococcal phages. After replication, SaPIbov2 is efficiently encapsidated and transferred to recipient organisms, including different non-Staphylococcus aureus staphylococci, where it integrates at a SaPI-specific attachment site, att(C), by means of a self-coded integrase (Int). Phages that cannot induce the SaPIbov2 ERP cycle can transfer the island by recA-dependent classical generalized transduction and can also transfer it by a novel mechanism that requires the expression of SaPIbov2 int in the recipient but not in the donor. It is suggested that this mechanism involves the encapsidation of standard transducing fragments containing the intact island followed by int-mediated excision, circularization, and integration in the recipient.
Maiques
Elisa
E
Centro de Investigación y Tecnología Animal, Instituto Valenciano de Investigaciones Agrarias, Apdo. 187, 12.400 Segorbe, Castellón, Spain.
Ubeda
Carles
C
Tormo
María Angeles
MA
Ferrer
María Desamparados
MD
Lasa
Iñigo
I
Novick
Richard P
RP
Penadés
José R
JR
D042003:DNA Packaging; D004261:DNA Replication; D004269:DNA, Bacterial / Q000235:genetics / Q000378:metabolism; D022761:Gene Transfer, Horizontal; D005816:Genetic Complementation Test; D044404:Genomic Islands / Q000235:genetics*; D019426:Integrases / Q000235:genetics* / Q000378:metabolism; D011938:Rec A Recombinases / Q000378:metabolism; D011995:Recombination, Genetic; D013204:Staphylococcus Phages / Q000235:genetics*; D013211:Staphylococcus aureus / Q000235:genetics* / Q000821:virology; D014161:Transduction, Genetic
D004269:DNA, Bacterial; D019426:Integrases; D011938:Rec A Recombinases