title: The Type I Restriction Enzymes as Barriers to Horizontal Gene Transfer: Determination of the DNA Target Sequences Recognised by Livestock-Associated Methicillin-Resistant Staphylococcus aureus Clonal Complexes 133/ST771 and 398.
abstract: The Type I DNA restriction-modification (RM) systems of Staphylococcus aureus are known to act as a significant barrier to horizontal gene transfer between S. aureus strains belonging to different clonal complexes. The livestock-associated clonal complexes CC133/771 and CC398 contain Type I RM systems not found in human MRSA strains as yet but at some point transfer will occur. When this does take place, horizontal gene transfer of resistance will happen more easily between these strains. The reservoir of antibiotic resistance, virulence and host-adaptation genes present in livestock-associated MRSA will then potentially contribute to the development of newly evolving MRSA clones. The target sites recognised by the Type I RM systems of CC133/771 and CC398 were identified as CAG(N)5RTGA and ACC(N)5RTGA, respectively. Assuming that these enzymes recognise the methylation state of adenine, the underlined A and T bases indicate the unique positions of methylation. Target methylation points for enzymes from CC1 were also identified. The methylation points for CC1-1 are CCAY(N)5TTAA and those for CC1-2 are CCAY(N)6 TGT with the underline indicating the adenine methylation site thus clearing up the ambiguity noted previously (Roberts et al. 2013, Nucleic Acids Res 41:7472-7484) for the half sites containing two adenine bases.
authors.affiliation: EaStCHEM School of Chemistry, University of Edinburgh the King's Buildings, Edinburgh, EH9 3JJ, UK.|Shenyang Research Institute of Chemical Industry, 8 Shenliao Dong Road, Shenyang, Liaoning, People's Republic of China.
authors.forename: Kai
authors.initials: K
authors.lastname: Chen
authors.affiliation: EaStCHEM School of Chemistry, University of Edinburgh the King's Buildings, Edinburgh, EH9 3JJ, UK.
authors.forename: Augoustinos S
authors.initials: AS
authors.lastname: Stephanou
authors.affiliation: EaStCHEM School of Chemistry, University of Edinburgh the King's Buildings, Edinburgh, EH9 3JJ, UK.
authors.forename: Gareth A
authors.initials: GA
authors.lastname: Roberts
authors.affiliation: EaStCHEM School of Chemistry, University of Edinburgh the King's Buildings, Edinburgh, EH9 3JJ, UK.
authors.forename: John H
authors.initials: JH
authors.lastname: White
authors.affiliation: EaStCHEM School of Chemistry, University of Edinburgh the King's Buildings, Edinburgh, EH9 3JJ, UK.
authors.forename: Laurie P
authors.initials: LP
authors.lastname: Cooper
authors.affiliation: Institute of Infection and Immunity, St George's, University of London, Cranmer Terrace, London, SW17 0RE, UK.|The Pirbright Institute, Ash Road, Pirbright, Woking, GU24 0NF, UK.
authors.forename: Patrick J
authors.initials: PJ
authors.lastname: Houston
authors.affiliation: Institute of Infection and Immunity, St George's, University of London, Cranmer Terrace, London, SW17 0RE, UK. jlindsay@sgul.ac.uk.
authors.forename: Jodi A
authors.initials: JA
authors.lastname: Lindsay
authors.affiliation: EaStCHEM School of Chemistry, University of Edinburgh the King's Buildings, Edinburgh, EH9 3JJ, UK. david.dryden@ed.ac.uk.
authors.forename: David T F
authors.initials: DT
authors.lastname: Dryden
mesh_terms: D000225:Adenine / Q000378:metabolism; D000595:Amino Acid Sequence; D000818:Animals; D000900:Anti-Bacterial Agents / Q000494:pharmacology; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism*; D001483:Base Sequence; D002417:Cattle; D019175:DNA Methylation; D004269:DNA, Bacterial / Q000235:genetics / Q000378:metabolism*; D015253:Deoxyribonucleases, Type I Site-Specific / Q000235:genetics / Q000378:metabolism*; D024881:Drug Resistance, Bacterial / Q000235:genetics; D022761:Gene Transfer, Horizontal; D005838:Genotype; D054884:Host-Pathogen Interactions; D058751:Livestock / Q000382:microbiology*; D055624:Methicillin-Resistant Staphylococcus aureus / Q000187:drug effects / Q000201:enzymology* / Q000235:genetics / Q000302:isolation & purification; D008892:Milk / Q000382:microbiology*; D008969:Molecular Sequence Data; D010641:Phenotype; D013203:Staphylococcal Infections / Q000188:drug therapy / Q000382:microbiology* / Q000635:transmission; D013379:Substrate Specificity; D014774:Virulence / Q000235:genetics
chemical_list: D000900:Anti-Bacterial Agents; D001426:Bacterial Proteins; D004269:DNA, Bacterial; D015253:Deoxyribonucleases, Type I Site-Specific; D000225:Adenine
keywords: Restriction enzyme; Staphylococcus aureus; Target recognition domain