2026-06-28T04:55:01Zhttps://docta.ucm.es/rest/oai/request

oai:docta.ucm.es:20.500.14352/451782023-12-04T18:51:47Zcom_20.500.14352_14col_20.500.14352_15

ArmA methyltransferase in a monophasic Salmonella enterica isolate from food Granier, Sophie A Hidalgo, Laura San Millán, Álvaro Gutiérrez, Belén Brisabois, Anne González Zorn, Bruno Escudero García-Calderón, José Antonio The 16S rRNA methyltransferase ArmA is a worldwide emerging determinant that confers high-level resistance to most clinically relevant aminoglycosides. We report here the identification and characterization of a multidrug-resistant Salmonella enterica subspecies I.4,12:i:- isolate recovered from chicken meat sampled in a supermarket on February 2009 in La Reunion, a French island in the Indian Ocean. Susceptibility testing showed an unusually high-level resistance to gentamicin, as well as to ampicillin, expanded-spectrum cephalosporins and amoxicillin-clavulanate. Molecular analysis of the 16S rRNA methyltransferases revealed presence of the armA gene, together with bla(TEM-1), bla(CMY-2), and bla(CTX-M-3). All of these genes could be transferred en bloc through conjugation into Escherichia coli at a frequency of 10(-5) CFU/donor. Replicon typing and S1 pulsed-field gel electrophoresis revealed that the armA gene was borne on an ~150-kb broad-host-range IncP plasmid, pB1010. To elucidate how armA had integrated in pB1010, a PCR mapping strategy was developed for Tn1548, the genetic platform for armA. The gene was embedded in a Tn1548-like structure, albeit with a deletion of the macrolide resistance genes, and an IS26 was inserted within the mel gene. To our knowledge, this is the first report of ArmA methyltransferase in food, showing a novel route of transmission for this resistance determinant. Further surveillance in food-borne bacteria will be crucial to determine the role of food in the spread of 16S rRNA methyltransferase genes worldwide. 2023-06-20T04:20:03Z 2023-06-20T04:20:03Z 2011-11 journal article 1098-6596 10.1128/AAC.00308-11 https://hdl.handle.net/20.500.14352/45178 http://aac.asm.org/content/early/2011/08/22/AAC.00308-11.full.pdf+html eng BIO2010/20204 VIGILANCIA SANITARIA-CM (S2009/AGR-1489) FOOD-CT-2004-506122 restricted access American Society for Microbiology