title: Biochemical basis of resistance to hygromycin B in Streptomyces hygroscopicus--the producing organism.
abstract: Hygromycin B, an aminocyclitol antibiotic that strongly inhibits both 70S and 80S ribosomes, is synthesized by Streptomyces hygroscopicus. Ribosomes from this Gram-positive mycelial bacterium are inhibited in vitro by the antibiotic. In contrast, the streptomycete is highly resistant to the drug in vivo since it possesses hygromycin B phosphotransferase activity. This enzyme has been shown by gel filtration to have a molecular weight of 42000, and to modify its antibiotic substrate to produce 7"-O-phosphoryl-hygromycin B which totally lacks biological activity both in vivo and in vitro.
mesh_terms: D000123:Acetyltransferases / Q000378:metabolism; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D055598:Chemical Phenomena; D002621:Chemistry; D004352:Drug Resistance, Microbial; D006921:Hygromycin B / Q000378:metabolism / Q000494:pharmacology*; D019868:Kanamycin Kinase; D007700:Kinetics; D008970:Molecular Weight; D010452:Peptide Biosynthesis; D010455:Peptides; D010766:Phosphorylation; D010770:Phosphotransferases / Q000378:metabolism; D013302:Streptomyces / Q000187:drug effects* / Q000201:enzymology
chemical_list: D000900:Anti-Bacterial Agents; D010455:Peptides; C012001:polyphenylalanine; D006921:Hygromycin B; D000123:Acetyltransferases; C019681:aminoglycoside acetyltransferase; D010770:Phosphotransferases; D019868:Kanamycin Kinase