Mercury-resistance and mercuric reductase activity in Chromobacterium, Erwinia, and Bacillus species

Journal Article · Mon Jun 01 00:00:00 EDT 1987 · Bull. Environ. Contam. Toxicol.; (United States)

DOI:https://doi.org/10.1007/BF01609097· OSTI ID:5503960

Trevors, J T

Mercury resistant bacteria have been the most extensively studied of all the metal-tolerant bacteria. Mercury resistance is usually mediated by two distinctly different enzymes encoded by plasmids. Mercuric reductase reduces Hg/sup 2 +/ to metallic mercury (Hg/sup 0/). Organomercurial lyases have a molecular weight of 20,000 to 40,000, are composed of 1 or 2 subunits and require the presence of thiol. Plasmic-encoded Hg/sup 2 +/ resistance and mercuric reductase activity have not been detected in many species of bacteria. A Chromobacterium, Erwinia and Bacillus species isolated from environmental samples were capable of growth in the presence of 50 ..mu..M HgCl/sub 2/. Cell-free extracts of the 3 organisms exhibited mercuric reductase activity that oxidized NADPH in the presence of HgCl/sub 2/. Negligible oxidation of NADPH was observed in the absence of HgCl/sub 2/. The Chromobacterium sp. did not contain any plasmid DNA. This would suggest that Hg/sup 2 +/ resistance was carried on the chromosome in Chromobacterium. A single 3 Mdal plasmid in the Bacillus sp. was refractory to curing. The Erwinia sp. contained 3 plasmids which were also refractory to curing. The location of the resistance genes is unknown in the Bacillus and Erwinia isolates.

• Research Organization: Univ. of Guelph, Ontario
• OSTI ID: 5503960
• Journal Information: Bull. Environ. Contam. Toxicol.; (United States), Journal Name: Bull. Environ. Contam. Toxicol.; (United States) Vol. 38:6; ISSN BECTA
• Country of Publication: United States
• Language: English

Related Subjects

560300* -- Chemicals Metabolism & Toxicology
63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
BACILLUS
BACTERIA
CELL CONSTITUENTS
CHEMICAL REACTIONS
CHLORIDES
CHLORINE COMPOUNDS
COENZYMES
ENZYME ACTIVITY
ENZYMES
HALIDES
HALOGEN COMPOUNDS
MERCURY CHLORIDES
MERCURY COMPOUNDS
MERCURY HALIDES
MICROORGANISMS
NADP
NUCLEOTIDES
ORGANIC COMPOUNDS
OXIDATION
OXIDOREDUCTASES
PLASMIDS
SENSITIVITY
TOXICITY