title: Necessity of the sulfoxide moiety for the biochemical and biological properties of an analog of sparsomycin.
abstract: An analog of the peptidyl transferase inhibitor sparsomycin was a competitive inhibitor (Ki = 1.8 microM) of peptidyl-puromycin synthesis on E. coli polysomes. Preincubation of polysomes with the compound enhanced the degree of inhibition of peptide bond formation. A model for the involvement of a histidine residue in peptidyl transferase activity is presented as a result of our observations which include direct association of [3H] labelled analog with 70S ribosomes. The correct oxidation state of sulfur in the compound was necessary for the "preincubation effect" and entry of the compound into bacterial cells.
mesh_terms: D000903:Antibiotics, Antineoplastic / Q000494:pharmacology*; D004926:Escherichia coli / Q000187:drug effects / Q000254:growth & development / Q000378:metabolism*; D007700:Kinetics; D011132:Polyribosomes / Q000187:drug effects / Q000378:metabolism*; D011691:Puromycin / Q000031:analogs & derivatives* / Q000096:biosynthesis; D012346:RNA, Transfer, Amino Acyl / Q000378:metabolism; D013033:Sparsomycin / Q000031:analogs & derivatives / Q000138:chemical synthesis / Q000494:pharmacology*; D013329:Structure-Activity Relationship
chemical_list: D000903:Antibiotics, Antineoplastic; D012346:RNA, Transfer, Amino Acyl; C031736:peptidyl-puromycin; D011691:Puromycin; C038801:MDL 19152; D013033:Sparsomycin