title: Molecular characterization of the pSinB plasmid of the arsenite oxidizing, metallotolerant Sinorhizobium sp. M14 - insight into the heavy metal resistome of sinorhizobial extrachromosomal replicons.
abstract: Sinorhizobium sp. M14 is an As(III)-oxidizing, psychrotolerant strain, capable of growth in the presence of extremely high concentrations of arsenic and many other heavy metals. Metallotolerant abilities of the M14 strain depend upon the presence of two extrachromosomal replicons: pSinA (∼ 109 kb) and pSinB (∼ 300 kb). The latter was subjected to complex analysis. The performed analysis demonstrated that the plasmid pSinB is a narrow-host-range repABC-type replicon, which is fully stabilized by the phd-vapC-like toxin-antitoxin stabilizing system. In silico analysis showed that among the phenotypic gene clusters of the plasmid pSinB, eight modules are potentially involved in heavy metals resistance (HMR). These modules carry genes encoding efflux pumps, permeases, transporters and copper oxidases, which provide resistance to arsenic, cadmium, cobalt, copper, iron, mercury, nickel, silver and zinc. The functional analysis revealed that the HMR modules are active and have an effect on the minimal inhibitory concentration (MIC) values observed for the heterological host cells. The phenotype was manifested by an increase or decrease of the MICs of heavy metals and it was strain specific. The analysis of distribution of the heavy metal resistance genes, i.e. resistome, in Sinorhizobium spp. plasmids, revealed that the HMR modules are common in these replicons.
authors: Department of Bacterial Genetics, Institute of Microbiology, Faculty of Biology, University of Warsaw, Miecznikowa 1, 02-096 Warsaw, Poland.
authors: Krzysztof
authors: K
authors: Romaniuk
authors: Department of Bacterial Genetics, Institute of Microbiology, Faculty of Biology, University of Warsaw, Miecznikowa 1, 02-096 Warsaw, Poland.
authors: Lukasz
authors: L
authors: Dziewit
authors: Department of Bacterial Genetics, Institute of Microbiology, Faculty of Biology, University of Warsaw, Miecznikowa 1, 02-096 Warsaw, Poland.
authors: Przemyslaw
authors: P
authors: Decewicz
authors: Laboratory of Environmental Pollution Analysis, Faculty of Biology, University of Warsaw, Miecznikowa 1, 02-096 Warsaw, Poland.
authors: Sebastian
authors: S
authors: Mielnicki
authors: Department of Virology, Institute of Microbiology, Faculty of Biology, University of Warsaw, Miecznikowa 1, 02-096 Warsaw, Poland.
authors: Monika
authors: M
authors: Radlinska
authors: Laboratory of Environmental Pollution Analysis, Faculty of Biology, University of Warsaw, Miecznikowa 1, 02-096 Warsaw, Poland.
authors: Lukasz
authors: L
authors: Drewniak
mesh_terms: D001151:Arsenic / Q000378:metabolism* / Q000633:toxicity; D018053:Arsenites / Q000378:metabolism; D001673:Biodegradation, Environmental; D001711:Biotransformation; D024881:Drug Resistance, Bacterial; D019216:Metals, Heavy / Q000378:metabolism* / Q000633:toxicity; D008826:Microbial Sensitivity Tests; D010957:Plasmids / Q000235:genetics; D012093:Replicon; D020579:Sinorhizobium / Q000187:drug effects / Q000235:genetics / Q000378:metabolism*
chemical_list: D018053:Arsenites; D019216:Metals, Heavy; C015001:arsenite; D001151:Arsenic
keywords: Sinorhizobium sp. M14; genomics; heavy metal resistome; plasmid pSinB; repABC system; toxin-antitoxin system