Evolved neomycin phosphotransferase from an isolate of Klebsiella pneumoniae.
Mol Microbiol, 1991/8;5(8):2039-46.
Lee KY[1], Hopkins JD, Syvanen M
Affiliations
PMID: 1662755
Impact factor: 3.979
Abstract
A new aminoglycoside resistance gene (aphA1-IAB) confers high-level resistance to neomycin. The sequence of aphA1-IAB is closely related to aphA1 found in the transposons Tn4352, Tn903 and Tn602. For example, aphA1-IAB differs from aphA1-903 at five nucleotides that result in four amino acid replacements. The enzyme encoded by aphA1-IAB has a significantly higher turnover number with neomycin, kanamycin and G418 as substrates than does the aphA1-903 enzyme. A parsimonious phylogenetic tree suggests that aphA1-IAB evolved from an ancestral form that is closely related or identical to the aphA1 found in Tn903. The excess of replacement substitutions over silent substitutions in aphA1-IAB, as well as its convergence toward aphA3 from Staphylococcus aureus, is indicative of selective evolution. Our hypothesis to explain these results is that aphA1-IAB evolved under the selective pressure of neomycin use in relatively recent times.
MeSH terms
Amino Acid Sequence; Base Sequence; Biological Evolution; Blotting, Western; DNA Transposable Elements; Drug Resistance, Microbial; Kanamycin; Kanamycin Kinase; Kinetics; Klebsiella pneumoniae; Molecular Sequence Data; Neomycin; Phosphotransferases; Plasmids; Sequence Homology, Nucleic Acid; Staphylococcus aureus; Temperature
More resources
EndNote: Download