title: The complete plasmid sequences of Salmonella enterica serovar Typhimurium U288.
abstract: Salmonella enterica Serovar Typhimurium U288 is an emerging pathogen of pigs. The strain contains three plasmids of diverse origin that encode traits that are of concern for food security and safety, these include antibiotic resistant determinants, an array of functions that can modify cell physiology and permit genetic mobility. At 148,711 bp, pSTU288-1 appears to be a hybrid plasmid containing a conglomerate of genes found in pSLT of S. Typhimurium LT2, coupled with a mosaic of horizontally-acquired elements. Class I integron containing gene cassettes conferring resistance against clinically important antibiotics and compounds are present in pSTU288-1. A curious feature of the plasmid involves the deletion of two genes encoded in the Salmonella plasmid virulence operon (spvR and spvA) following the insertion of a tnpA IS26-like element coupled to a blaTEM gene. The spv operon is considered to be a major plasmid-encoded Salmonella virulence factor that is essential for the intracellular lifecycle. The loss of the positive regulator SpvR may impact on the pathogenesis of S. Typhimurium U288. A second 11,067 bp plasmid designated pSTU288-2 contains further antibiotic resistance determinants, as well as replication and mobilization genes. Finally, a small 4675 bp plasmid pSTU288-3 was identified containing mobilization genes and a pleD-like G-G-D/E-E-F conserved domain protein that modulate intracellular levels of cyclic di-GMP, and are associated with motile to sessile transitions in growth.
authors.affiliation: Division of Food Sciences, School of Biosciences, University of Nottingham, Sutton Bonington Campus, Loughborough LE12 5RD, UK.
authors.forename: Steven P T
authors.initials: SP
authors.lastname: Hooton
authors.affiliation: Division of Food Sciences, School of Biosciences, University of Nottingham, Sutton Bonington Campus, Loughborough LE12 5RD, UK.
authors.forename: Andrew R
authors.initials: AR
authors.lastname: Timms
authors.affiliation: Division of Food Sciences, School of Biosciences, University of Nottingham, Sutton Bonington Campus, Loughborough LE12 5RD, UK.
authors.forename: Nicola J
authors.initials: NJ
authors.lastname: Cummings
authors.affiliation: School of Veterinary Medicine and Science, University of Nottingham, Sutton Bonington Campus, Loughborough LE12 5RD, UK.
authors.forename: Joanna
authors.initials: J
authors.lastname: Moreton
authors.affiliation: DeepSeq, Queens Medical Centre, University of Nottingham, Nottingham NG7 2UH, UK.
authors.forename: Ray
authors.initials: R
authors.lastname: Wilson
authors.affiliation: Division of Food Sciences, School of Biosciences, University of Nottingham, Sutton Bonington Campus, Loughborough LE12 5RD, UK. Electronic address: ian.connerton@nottingham.ac.uk.
authors.forename: Ian F
authors.initials: IF
authors.lastname: Connerton
mesh_terms: D003227:Conjugation, Genetic; D024881:Drug Resistance, Bacterial / Q000235:genetics*; D022761:Gene Transfer, Horizontal; D032023:Integrons; D010957:Plasmids / Q000187:drug effects / Q000235:genetics*; D012486:Salmonella typhimurium / Q000235:genetics* / Q000472:pathogenicity; D017422:Sequence Analysis, DNA
keywords: Antibiotic resistance; G-G-D/E-E-F domain; Hybrid virulence plasmid; Salmonella Typhimurium U288; Transposable element; spv operon