Structure-function analyses for aminoglycoside 3'-phosphotransferase II (APH(3')-II).

S Kocabiyik; C Mullins; C Breeding; M H Perlin

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PubMed · 1369370

Structure-function analyses for aminoglycoside 3'-phosphotransferase II (APH(3')-II).

S Kocabiyik·C Mullins·C Breeding·M H Perlin

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Abstract

Mutant strains containing APH(3')-II were constructed via site-directed mutagenesis of the cloned gene and by random mutagenesis of a strain containing the APH(3')-II gene on a conjugative plasmid. Substitutions at highly conserved amino acid residues produced APH(3') enzymes which in general showed reduced activity and conferred reduced levels of resistance to their substrates. Substitutions at Tyr 218 altered substrate specificity for the enzymes. Random mutagenesis produced plasmid-borne mutations conferring amikacin resistance. Two of these mutations appeared to be localized to the APH(3')-II structural gene.

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Amino Acid Sequence Escherichia coli Kanamycin Kinase Kinetics Molecular Sequence Data Mutagenesis, Site-Directed Phosphotransferases Plasmids Pseudomonas Salmonella typhimurium Sequence Homology, Nucleic Acid Structure-Activity Relationship Substrate Specificity Comparative Study Journal Article Research Support, U.S. Gov't, P.H.S.

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S Kocabiyik, C Mullins, C Breeding, M H Perlin. 1992. Structure-function analyses for aminoglycoside 3'-phosphotransferase II (APH(3')-II).. https://pubmed.ncbi.nlm.nih.gov/1369370/

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