title: Heavy metal resistance in Cupriavidus metallidurans CH34 is governed by an intricate transcriptional network.
abstract: The soil bacterium Cupriavidus metallidurans CH34 contains a high number of heavy metal resistance genes making it an interesting model organism to study microbial responses to heavy metals. In this study the transcriptional response of strain CH34 was measured when challenged to sub-lethal concentrations of various essential or toxic metals. Based on the global transcriptional responses for each challenge and the overlap in upregulated genes between different metal responses, the sixteen metals were clustered in three groups. In addition, the transcriptional response of already known metal resistance genes was assessed, and new metal response gene clusters were identified. The majority of the studied metal response loci showed similar expression profiles when cells were exposed to different metals, suggesting complex interplay at transcriptional level between the different metal responses. The pronounced redundancy of these metal resistant regions-as illustrated by the large number of paralogous genes-combined with the phylogenetic distribution of these metal response regions within either evolutionary related or other metal resistant bacteria, provides important insights on the recent evolutionary forces shaping this naturally soil-dwelling bacterium into a highly metal-resistant strain well adapted to harsh and anthropogenic environments.
authors.affiliation: Molecular and Cellular Biology, Belgian Nuclear Research Centre (SCK·CEN), Boeretang 200, Mol, Belgium. Pieter.Monsieurs@sckcen.be
authors.forename: Pieter
authors.initials: P
authors.lastname: Monsieurs
authors.forename: Hugo
authors.initials: H
authors.lastname: Moors
authors.forename: Rob
authors.initials: R
authors.lastname: Van Houdt
authors.forename: Paul J
authors.initials: PJ
authors.lastname: Janssen
authors.forename: Ann
authors.initials: A
authors.lastname: Janssen
authors.forename: Ilse
authors.initials: I
authors.lastname: Coninx
authors.forename: Max
authors.initials: M
authors.lastname: Mergeay
authors.forename: Natalie
authors.initials: N
authors.lastname: Leys
mesh_terms: D002876:Chromosomes, Bacterial; D049921:Cupriavidus / Q000145:classification / Q000235:genetics* / Q000378:metabolism*; D020869:Gene Expression Profiling; D015964:Gene Expression Regulation, Bacterial; D053263:Gene Regulatory Networks; D005798:Genes, Bacterial; D019216:Metals, Heavy / Q000378:metabolism*; D046228:Microarray Analysis; D005810:Multigene Family; D010802:Phylogeny
chemical_list: D019216:Metals, Heavy