Nucleotide sequence of a chromosomal mercury resistance determinant from a Bacillus sp. with broad-spectrum mercury resistance. [Mercury reductase]

Journal Article · Sun Jan 01 04:00:00 EST 1989 · Journal of Bacteriology; (USA)

OSTI ID:6969001

Wang, Y; Levinson, H S; Mahler, I ^[1]; Moore, M; Walsh, C ^[2]; Silver, S ^[3]

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1. Brandeis Univ., Waltham, MA (USA)
2. Harvard Medical School, Boston, MA (USA)
3. Univ. of Illinois College of Medicine, Chicago (USA)

A 13.5-kilobase HindIII fragment, bearing an intact mercury resistance (mer) operon, was isolated from chromosomal DNA of broad-spectrum mercury-resistant Bacillus sp. strain RC607 by using as a probe a clone containing the mercury reductase (merA) gene. The new clone, pYW33, expressed broad-spectrum mercury resistance both in Escherichia coli and in Bacillus subtilis, but only in B. subtilis was the mercuric reductase activity inducible. Sequencing of a 1.8-kilobase mercury hypersensitivity-producing fragment revealed four open reading frames (ORFs). ORF1 may code for a regulatory protein (MerR). ORF2 and ORF4 were associated with cellular transport function and the hypersensitivity phenotype. DNA fragments encompassing the merA and the merB genes were sequenced. The predicted Bacillus sp. strain RC607 MerA (mercuric reductase) and MerB (organomercurial lyase) were similar to those predicted from Staphylococcus aureus plasmid pI258 (67 and 73% amino acid identities, respectively); however, only 40% of the amino acid residues of RC607 MerA were identical to those of the mercuric reductase from gram-negative bacteria. A 69-kilodalton polypeptide was isolated and identified as the merA gene product by examination of its amino-terminal sequence.

• OSTI ID: 6969001
• Journal Information: Journal of Bacteriology; (USA), Journal Name: Journal of Bacteriology; (USA) Vol. 171:1; ISSN JOBAA; ISSN 0021-9193
• Country of Publication: United States
• Language: English

Related Subjects

550200* -- Biochemistry
560300 -- Chemicals Metabolism & Toxicology
59 BASIC BIOLOGICAL SCIENCES
63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
BACILLUS
BACTERIA
DNA SEQUENCING
ELEMENTS
ENZYMES
GENE OPERONS
MERCURY
METALS
MICROORGANISMS
MOLECULAR BIOLOGY
OXIDOREDUCTASES
PHENOTYPE
STRUCTURAL CHEMICAL ANALYSIS
TOLERANCE
TOXICITY