Nucleotide sequence of the transposon Tn7 gene encoding an aminoglycoside-modifying enzyme, 3"(9)-O-nucleotidyltransferase

Nucleic Acids Res. 1985 Oct 11;13(19):7095-106. doi: 10.1093/nar/13.19.7095.


The nucleotide sequence of a transposon Tn7 DNA fragment encoding a 3"(9)-O-nucleotidyltransferase, an aminoglycoside-modifying enzyme, which mediates bacterial resistance to spectinomycin and streptomycin, was determined. The aadA structural gene was 786 bases long and predicted a polypeptide of 262 amino acids with a calculated molecular weight of 29,207. Comparison of the DNA sequences of Tn7 and plasmid R538-1 indicated that their aadA genes were nearly identical. Comparison of the polypeptides predicted by the aadA genes of Tn7 and Tn554 indicated that the genes were related.

MeSH terms

  • Amino Acid Sequence
  • Bacteria / enzymology
  • Base Sequence
  • Biological Evolution
  • Cloning, Molecular
  • DNA Transposable Elements*
  • DNA, Bacterial / genetics
  • Drug Resistance, Microbial*
  • Escherichia coli / enzymology
  • Escherichia coli / genetics
  • Genes, Bacterial
  • Nucleotidyltransferases / genetics*
  • Repetitive Sequences, Nucleic Acid
  • Sequence Homology, Nucleic Acid
  • Spectinomycin / metabolism
  • Spectinomycin / pharmacology*
  • Streptomycin / metabolism
  • Streptomycin / pharmacology*


  • DNA Transposable Elements
  • DNA, Bacterial
  • Spectinomycin
  • Nucleotidyltransferases
  • Streptomycin

Associated data

  • GENBANK/X03043