title: [Aminoglycoside-3'-phosphotransferase I from aminoglycoside-polyresistant strain E. coli 182].
abstract: An aminoglycoside-3'-phosphotransferase I catalyzing phosphorylation of some aminoglycoside antibiotics with the 3'-hydroxyl group has been purified from the cells of aminoglycoside resistant strain E. coli 182 by competitive affinity chromatography on neomycin-Sepharose and gel-filtration on Sephadex G-100. The product of enzymatic phosphorylation of kanamycin A was isolated and identified as kanamycin-3'-phosphate by NMR, thin-layer chromatography and chemical characterization. The kinetic properties of the enzyme were studied. The pH-optimum was between 7,8--8,0; the [S]0.5 values for kanamycin, neomycin and paromomycin were 2.10(-5) M, the energy of activation was 15,9 kcal/mol. The bivalent cations were required for activity of the enzyme, Mg2+ was the most effecient. The relative aminoglycoside antibiotics containing no 3'-hydroxyl group were competitive inhibitors of the enzyme activity with Ki values close to [S]0.5.
mesh_terms: D000617:Aminoglycosides; D000900:Anti-Bacterial Agents; D004352:Drug Resistance, Microbial; D004789:Enzyme Activation; D004926:Escherichia coli / Q000201:enzymology*; D007700:Kinetics; D010770:Phosphotransferases / Q000302:isolation & purification / Q000378:metabolism*
chemical_list: D000617:Aminoglycosides; D000900:Anti-Bacterial Agents; D010770:Phosphotransferases
vernacular_title: Aminoglikozid-3'-fosfotransferaza I iz kletok E. Coli 182 s mnozhestvennoĭ ustoĭchivost'iu k aminoglikozidnym antibiotikam.