title: Ralstonia metallidurans, a bacterium specifically adapted to toxic metals: towards a catalogue of metal-responsive genes.
abstract: Ralstonia metallidurans, formerly known as Alcaligenes eutrophus and thereafter as Ralstonia eutropha, is a beta-Proteobacterium colonizing industrial sediments, soils or wastes with a high content of heavy metals. The type strain CH34 carries two large plasmids (pMOL28 and pMOL30) bearing a variety of genes for metal resistance. A chronological overview describes the progress made in the knowledge of the plasmid-borne metal resistance mechanisms, the genetics of R. metallidurans CH34 and its taxonomy, and the applications of this strain in the fields of environmental remediation and microbial ecology. Recently, the sequence draft of the genome of R. metallidurans has become available. This allowed a comparison of these preliminary data with the published genome data of the plant pathogen Ralstonia solanacearum, which harbors a megaplasmid (of 2.1 Mb) carrying some metal resistance genes that are similar to those found in R. metallidurans CH34. In addition, a first inventory of metal resistance genes and operons across these two organisms could be made. This inventory, which partly relied on the use of proteomic approaches, revealed the presence of numerous loci not only on the large plasmids pMOL28 and pMOL30 but also on the chromosome. It suggests that metal-resistant Ralstonia, through evolution, are particularly well adapted to the harsh environments typically created by extreme anthropogenic situations or biotopes.
authors.affiliation: Laboratories for Microbiology and Radiobiology, Belgium Nuclear Research Center, SCK/CEN, B-2400 Mol, Belgium. mmergeay@sckcen.be
authors.forename: Max
authors.initials: M
authors.lastname: Mergeay
authors.forename: Sébastien
authors.initials: S
authors.lastname: Monchy
authors.forename: Tatiana
authors.initials: T
authors.lastname: Vallaeys
authors.forename: Vanessa
authors.initials: V
authors.lastname: Auquier
authors.forename: Abderrafi
authors.initials: A
authors.lastname: Benotmane
authors.forename: Philippe
authors.initials: P
authors.lastname: Bertin
authors.forename: Safiyh
authors.initials: S
authors.lastname: Taghavi
authors.forename: John
authors.initials: J
authors.lastname: Dunn
authors.forename: Daniel
authors.initials: D
authors.lastname: van der Lelie
authors.forename: Ruddy
authors.initials: R
authors.lastname: Wattiez
mesh_terms: D000251:Adenosine Triphosphatases / Q000145:classification / Q000378:metabolism; D000595:Amino Acid Sequence; D024881:Drug Resistance, Bacterial / Q000235:genetics*; D005798:Genes, Bacterial / Q000235:genetics; D023281:Genomics; D008670:Metals / Q000378:metabolism / Q000494:pharmacology* / Q000633:toxicity; D008957:Models, Genetic; D005810:Multigene Family; D010802:Phylogeny; D010957:Plasmids / Q000235:genetics; D020560:Proteobacteria / Q000187:drug effects / Q000235:genetics* / Q000378:metabolism; D016415:Sequence Alignment
chemical_list: D008670:Metals; D000251:Adenosine Triphosphatases