title: A novel ICE in the genome of Shewanella putrefaciens W3-18-1: comparison with the SXT/R391 ICE-like elements.
abstract: A novel R391-like ICE (integrating conjugative element) has been detected in the 4.2 MB genome of Shewanella putrefaciens W3-18-1 located on three different contigs. Assembly of the ICE encoding contigs based on similarity with R391 revealed a mosaic element of plasmid, phage and transposon-like sequences typical of SXT/R391 ICE-like elements. The element, which is 110 057 bp in length, was highly similar to R391 sequences, with most related ORFs showing >96% amino acid sequence identity. The element, designated ICESpuPO1, contained a number of inserts determining resistance to copper and other heavy metals and a broad-spectrum RND efflux pump similar to antibiotic efflux systems. The element was integrated into the Shewanella prfC gene in a manner similar to related ICE-like elements. The chromosomal element junctions contained a 17-bp SXT/R391-like attL and attR site and an unannotated ORF between attL and the ICE integrase encoding a putative recombinational directional factor necessary for excision, with 100% amino acid identity to the R391 ORF4 product.
authors.affiliation: Molecular and Structural Biochemistry Laboratory, Department of Chemical and Environmental Sciences, University of Limerick, Limerick, Ireland. tony.pembroke@ul.ie
authors.forename: J Tony
authors.initials: JT
authors.lastname: Pembroke
authors.forename: Anna V
authors.initials: AV
authors.lastname: Piterina
mesh_terms: D001426:Bacterial Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D004251:DNA Transposable Elements; D016680:Genome, Bacterial; D019426:Integrases / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D016366:Open Reading Frames; D010454:Peptide Termination Factors / Q000737:chemistry / Q000235:genetics; D020614:Shewanella putrefaciens / Q000201:enzymology / Q000235:genetics* / Q000302:isolation & purification
chemical_list: D001426:Bacterial Proteins; D004251:DNA Transposable Elements; D010454:Peptide Termination Factors; C087971:peptide-chain-release factor 3; D019426:Integrases