title: Epidemic multidrug-resistant (MDR-AmpC) Salmonella enterica serovar Newport strains contain three phage regions and a MDR resistance plasmid.
abstract: Multidrug-resistant (MDR-AmpC) Salmonella enterica serovar Newport has caused serious disease in animals and humans in North America, whereas in the UK S. enterica serovar Newport is not associated with severe disease and usually sensitive to antibiotics; MDR S. Newport (not AmpC) strains have only been isolated from poultry. We found that UK poultry strains belonged to MLST type ST166 and were distinct from cattle isolates for being able to utilize D-tagotose and when compared by pulsed-field gel electrophoresis (PFGE), comparative genomic hybridization (CGH) and diversity arrays technology (DArT). Cattle strains belonged to the ST45 complex differing from ST166 at all seven loci. PFGE showed that 19 out of 27 cattle isolates were more than 85% similar to each other and some UK and US strains were indistinguishable. Both CGH and DArT identified genes (including phage-related ones) that were uniquely present in the US isolates and two such genes identified by DArT showed sequence similarities with the pertussis-like (artAB) toxin. This work demonstrates that MDR-AmpC S. Newport from the USA are genetically closely related to pan-susceptible strains from the UK, but contained three extra phage regions and a MDR plasmid.
authors.affiliation: Department for Food and Environmental Safety, Veterinary Laboratories Agency (VLA)-Weybridge, Woodham Lane, New Haw, Addlestone, Surrey KT13 3NB, UK. AIT Austrian Institute of Technology GmbH, Bioresources Unit, 2444 Seibersdorf, Austria. The Pathogen Genetics Group, The Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Hinxton, Cambridge CB10 1SA, UK. Diversity Arrays Technology Pty Ltd, Yarralumla, Canberra, ACT 2600, Australia.
authors.forename: Guanghui
authors.initials: G
authors.lastname: Wu
authors.forename: Manal
authors.initials: M
authors.lastname: Abuoun
authors.forename: Evelyn
authors.initials: E
authors.lastname: Hackl
authors.forename: Roberto M
authors.initials: RM
authors.lastname: La Ragione
authors.forename: Maria
authors.initials: M
authors.lastname: Fookes
authors.forename: Jackie
authors.initials: J
authors.lastname: Fenner
authors.forename: Zhensheng
authors.initials: Z
authors.lastname: Pan
authors.forename: Peter
authors.initials: P
authors.lastname: Wenzl
authors.forename: Muna F
authors.initials: MF
authors.lastname: Anjum
authors.forename: Martin J
authors.initials: MJ
authors.lastname: Woodward