title: Nucleotide sequence of a gene from the Pseudomonas transposon Tn501 encoding mercuric reductase.
abstract: We have determined the nucleotide sequence of the merA gene from the mercury-resistance transposon Tn501 and have predicted the structure of the gene product, mercuric reductase. The DNA sequence predicts a polypeptide of Mr 58 660, the primary structure of which shows strong homologies to glutathione reductase and lipoamide dehydrogenase, but mercuric reductase contains as additional N-terminal region that may form a separate domain. The implications of these comparisons for the tertiary structure and mechanism of mercuric reductase are discussed. The DNA sequence presented here has an overall G+C content of 65.1 mol%, typical of the bulk DNA of Pseudomonas aeruginosa from which Tn501 was originally isolated. Analysis of the codon usage in the merA gene shows that codons with C or G at the third position are preferentially utilized.
mesh_terms: D000595:Amino Acid Sequence; D001483:Base Sequence; D004251:DNA Transposable Elements; D004926:Escherichia coli / Q000235:genetics; D005796:Genes; D005798:Genes, Bacterial; D010088:Oxidoreductases / Q000235:genetics*; D010641:Phenotype; D010957:Plasmids; D011550:Pseudomonas aeruginosa / Q000201:enzymology* / Q000235:genetics
chemical_list: D004251:DNA Transposable Elements; D010088:Oxidoreductases; C021551:mercuric reductase