title: The mercury resistance (mer) operon in a marine gliding flavobacterium, Tenacibaculum discolor 9A5.
abstract: Genes conferring mercury resistance have been investigated in a variety of bacteria and archaea but not in bacteria of the phylum Bacteroidetes, despite their importance in many environments. We found, however, that a marine gliding Bacteroidetes species, Tenacibaculum discolor, was the predominant mercury-resistant bacterial taxon cultured from a salt marsh fertilized with mercury-contaminated sewage sludge. Here we report characterization of the mercuric reductase and the narrow-spectrum mercury resistance (mer) operon from one of these strains - T. discolor 9A5. This mer operon, which confers mercury resistance when cloned into Flavobacterium johnsoniae, encodes a novel mercury-responsive ArsR/SmtB family transcriptional regulator that appears to have evolved independently from other mercury-responsive regulators, a novel putative transport protein consisting of a fusion between the integral membrane Hg(II) transporter MerT and the periplasmic Hg(II)-binding protein MerP, an additional MerP protein, and a mercuric reductase that is phylogenetically distinct from other known mercuric reductases.
authors: Program in Molecular Biology, Pomona College, Claremont, CA, USA.
authors: Rachel C
authors: RC
authors: Allen
authors: Yen-Kuei
authors: YK
authors: Tu
authors: Michael J
authors: MJ
authors: Nevarez
authors: Alexander S
authors: AS
authors: Bobbs
authors: Joseph W
authors: JW
authors: Friesen
authors: Jon R
authors: JR
authors: Lorsch
authors: John A
authors: JA
authors: McCauley
authors: Judith G
authors: JG
authors: Voet
authors: Nancy V
authors: NV
authors: Hamlett
mesh_terms: D000595:Amino Acid Sequence; D003001:Cloning, Molecular; D004269:DNA, Bacterial / Q000235:genetics / Q000302:isolation & purification; D008628:Mercury / Q000378:metabolism*; D008969:Molecular Sequence Data; D009876:Operon; D010088:Oxidoreductases / Q000235:genetics* / Q000302:isolation & purification; D010802:Phylogeny; D016415:Sequence Alignment; D017422:Sequence Analysis, DNA; D012722:Sewage / Q000737:chemistry; D012989:Soil Pollutants / Q000378:metabolism; D060493:Tenacibaculum / Q000201:enzymology / Q000235:genetics*; D053833:Wetlands
chemical_list: D004269:DNA, Bacterial; D012722:Sewage; D012989:Soil Pollutants; D010088:Oxidoreductases; C021551:mercuric reductase; D008628:Mercury