Nucleotide sequence of a gene from the Pseudomonas transposon Tn501 encoding mercuric reductase

Biochemistry. 1983 Aug 16;22(17):4089-95. doi: 10.1021/bi00286a015.


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.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Base Sequence
  • DNA Transposable Elements*
  • Escherichia coli / genetics
  • Genes*
  • Genes, Bacterial*
  • Oxidoreductases / genetics*
  • Phenotype
  • Plasmids
  • Pseudomonas aeruginosa / enzymology*
  • Pseudomonas aeruginosa / genetics


  • DNA Transposable Elements
  • Oxidoreductases
  • mercuric reductase

Associated data

  • GENBANK/K00031