title: Isolation and genomic characterization of the first phage infecting Iodobacteria: ϕPLPE, a myovirus having a novel set of features.
abstract: The aquatic phage ϕPLPE infects a bacterium of the genus Iodobacter that are common inhabitants of rivers, streams and canals that produce violacein-like pigments. Our characterization of ϕPLPE reveals it to be a small, contractile-tailed phage whose 47.5 kb genome sequence is phylogenetically distant from all previously characterized phages. The genome has a generally modular organization (e.g. replication/recombination, structure/morphogenesis, lysis/lysogeny) and approximately half of its 84 open reading frames have no known homologues. It behaves as a virulent phage under the host growth conditions we have employed and, with the exception of an anti-repressor (ant) homologue, the genome lacks all the genes associated with a lysogenic lifestyle. Thus, either ϕPLPE was once a temperate phage that has lost most of its lysogeny cassette or it is a virulent phage that acquired an ant-like gene presumably for some function other than the control of lysogeny. The ϕPLPE genome has few bacterial gene homologues with the interesting exception of a putative acylhydrolase (acylase). This function has been implicated in bacterial quorum sensing since it degrades homoserine-lactone signalling molecules and can disrupt or modulate quorum signalling from either the emitter or its competitors. ϕPLPE may be an example of a phage co-opting components of the bacterial quorum-sensing apparatus to its own advantage.
authors.affiliation: Centre National de la Recherche Scientifique, LMGM, F-31000 Toulouse, France. Université de Toulouse, UPS, Laboratoire de Microbiologie et Génétique Moléculaires, F-31000 Toulouse, France.
authors.forename: Cécile
authors.initials: C
authors.lastname: Leblanc
authors.forename: Anne
authors.initials: A
authors.lastname: Caumont-Sarcos
authors.forename: André M
authors.initials: AM
authors.lastname: Comeau
authors.forename: Henry M
authors.initials: HM
authors.lastname: Krisch