title: Inhibition of antiassociation activity of translation initiation factor 3 by paromomycin.
abstract: The effect of paromomycin on the interaction of ribosomal subunits was studied. Paromomycin inhibited the antiassociation activity of initiation factor 3 (IF3). Furthermore, ribosomal subunits were associated to form 70S ribosomes by paromomycin even in the presence of 1 mM Mg(2+). Paromomycin did not inhibit the binding of IF3 to the 30S ribosomal subunits. On the other hand, IF3 bound to the 30S subunits was expelled by paromomycin-induced subunit association (70S formation). These results indicate that the stabilization of 70S ribosomes by paromomycin may in part be responsible for its inhibitory effects on translocation and ribosome recycling.
authors.affiliation: Department of Biochemistry and Molecular Biology, Jefferson Medical College, Thomas Jefferson University, 1020 Locust Street, JAH 456A, Philadelphia, PA 19107, USA.
authors.forename: Go
authors.initials: G
authors.lastname: Hirokawa
authors.forename: Hideko
authors.initials: H
authors.lastname: Kaji
authors.forename: Akira
authors.initials: A
authors.lastname: Kaji
mesh_terms: D004926:Escherichia coli / Q000187:drug effects / Q000235:genetics; D029968:Escherichia coli Proteins / Q000378:metabolism; D008274:Magnesium / Q000494:pharmacology; D010303:Paromomycin / Q000494:pharmacology*; D039665:Prokaryotic Initiation Factor-3 / Q000037:antagonists & inhibitors / Q000378:metabolism*; D011485:Protein Binding / Q000187:drug effects; D012269:Ribosomal Proteins / Q000378:metabolism; D012270:Ribosomes / Q000378:metabolism*
chemical_list: D029968:Escherichia coli Proteins; D039665:Prokaryotic Initiation Factor-3; D012269:Ribosomal Proteins; D010303:Paromomycin; D008274:Magnesium