Nucleotide and deduced protein sequences of the class D tetracycline resistance determinant: relationship to other antimicrobial transport proteins.
The nucleotide sequence of the plasmid pRA1 gene encoding the TetA(D) tetracycline/H+ antiporter was determined. The deduced amino acid sequence was compared with those of other antimicrobial and antiseptic transporters. The deduced product of tetA(D) is a 41.1-kDa protein consisting of 394 amino acids comprising 12 membrane-spanning domains. Three classes of amino acid motifs found in TetA(D) are highly conserved in other transporters, implying that they participate in structures necessary for substrate recognition, binding, or translocation. A common mechanism of transport is suggested, with subtle sequence variations accounting for varied substrate specificities, modes of transport, and directions of transport.
Varela
M F
MF
Department of Cell Biology, School of Medicine, University of New Mexico, Albuquerque 87131.
Griffith
J K
JK
D000595:Amino Acid Sequence; D017920:Antiporters; D001426:Bacterial Proteins / Q000235:genetics*; D001483:Base Sequence; D002352:Carrier Proteins / Q000235:genetics*; D004352:Drug Resistance, Microbial; D008969:Molecular Sequence Data; D012097:Repressor Proteins / Q000235:genetics*; D017386:Sequence Homology, Amino Acid; D013753:Tetracycline Resistance / Q000235:genetics*
D017920:Antiporters; D001426:Bacterial Proteins; D002352:Carrier Proteins; D012097:Repressor Proteins; C079051:tetA protein, Bacteria