title: Mercuric reductase in environmental gram-positive bacteria sensitive to mercury.
abstract: According to existing data, mercury resistance operons (mer operons) are in general thought to be rare in bacteria, other than those from mercury-contaminated sites. We have found that a high proportion of strains in environmental isolates of Gram-positive bacteria express mercuric reductase (MerA protein): the majority of these strains are apparently sensitive to mercury. The expression of MerA was also inducible in all cases. These results imply the presence of phenotypically cryptic mer resistance operons, with both the merA (mercuric reductase) and merR (regulatory) genes still present, but the possible absence of the transport function required to complete the resistance mechanism. This indicates that mer operons or parts thereof are more widely spread in nature than is suggested by the frequency of mercury-resistant bacteria.
authors.affiliation: Institute of Molecular Genetics, Russian Academy of Sciences, Moscow.
authors.forename: E S
authors.initials: ES
authors.lastname: Bogdanova
authors.forename: S Z
authors.initials: SZ
authors.lastname: Mindlin
authors.forename: E
authors.initials: E
authors.lastname: Pakrová
authors.forename: M
authors.initials: M
authors.lastname: Kocur
authors.forename: D A
authors.initials: DA
authors.lastname: Rouch
mesh_terms: D004352:Drug Resistance, Microbial / Q000235:genetics; D004783:Environmental Microbiology; D005798:Genes, Bacterial; D006094:Gram-Positive Bacteria / Q000187:drug effects* / Q000201:enzymology* / Q000235:genetics; D008628:Mercury / Q000494:pharmacology*; D008826:Microbial Sensitivity Tests; D009876:Operon; D010088:Oxidoreductases / Q000235:genetics / Q000378:metabolism*; D013045:Species Specificity
chemical_list: D010088:Oxidoreductases; C021551:mercuric reductase; D008628:Mercury