%0 Journal Article %A Sugiyama, Masanori %A Sakamoto, Makoto %A Mochizuki, Hiroshi %A Nimi, Osamu %A Nomi, Ryosaku %T Purification and Characterization of Streptomycin 6-kinase, an Enzyme Implicated in Self-protection of a Streptomycin-producing Micro-organism %D 1983 %J Microbiology, %V 129 %N 6 %P 1683-1687 %@ 1465-2080 %R https://doi.org/10.1099/00221287-129-6-1683 %I Microbiology Society, %X Streptomycin 6-kinase of the streptomycin-producing strain Streptomyces griseus HUT 6037 was purified by fractionation with (NH4)2SO4 and chromatography on DEAE-Sephadex A-25, hydroxyapatite and Sephadex G-100. After PAGE of the final fraction, a protein band corresponding to streptomycin 6-kinase was detected, together with a less intense band having no enzyme activity. Molecular weights determined by SDS-PAGE and by Sephadex G-100 chromatography were about 36000 and 38000, respectively, suggesting that the enzyme was a monomer. The isoelectric point of the enzyme was pH 6.6. Among the nucleoside 5′-triphosphates tested, ATP was the preferred phosphoryl donor. The Km values for streptomycin and ATP were 3.5 mm and 0·4 mm , respectively. The enzyme activity was strongly inhibited by EDTA and AgNO3. It was shown by using an in vitro protein-synthesizing system that purified streptomycin 6-kinase could protect polyphenylalanine synthesis of the streptomycin-susceptible S. griseus strain KSN from inhibition by streptomycin. %U https://www.microbiologyresearch.org/content/journal/micro/10.1099/00221287-129-6-1683