Nucleotide sequence of class D tetracycline resistance genes from Salmonella ordonez

Mol Gen Genet. 1993 Feb;237(1-2):301-5. doi: 10.1007/BF00282811.


Plasmid pIP173, isolated from Salmonella ordonez strain BM2000, confers resistance to tetracycline and a number of other antibiotics. We determined the nucleotide sequence of the pIP173 tetR repressor and tetA resistance genes. The pIP173 tetR gene is essentially identical to the class D tetR gene from plasmid RA1. The pIP173 tet genes are flanked by directly repeated copies of the insertion sequence IS26. Interestingly, the 3' end of the tetR gene, encoding the C-terminal 16 amino acids of the TetR protein, extends into the flanking IS26 sequence. The relationships between the class A, B, C, and D TetA sequences parallel the relationships between the corresponding TetR sequences; class D is more closely related to class B than to either class A or C. Overall, the four TetA sequences show 38% identity and 57% similarity.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Amino Acid Sequence
  • Base Sequence
  • Chromosome Mapping
  • DNA Transposable Elements / genetics
  • Genes, Bacterial / genetics*
  • Molecular Sequence Data
  • Plasmids / genetics
  • R Factors / genetics*
  • Repressor Proteins / genetics*
  • Salmonella / genetics*
  • Sequence Homology, Amino Acid
  • Tetracycline Resistance / genetics*


  • DNA Transposable Elements
  • Repressor Proteins
  • tetracycline resistance-encoding transposon repressor protein

Associated data

  • GENBANK/X65876