HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Lockwood, A. H. Articles by Weissbach, H. Search for Related Content PubMed PubMed Citation Articles by Lockwood, A. H. Articles by Weissbach, H. Social Bookmarking                      What's this?

Effect of Thiostrepton on Polypeptide Chain Initiation in Escherichia coli

From the ¹ From the Department of Developmental Biology and Cancer, Albert Einstein College of Medicine, Bronx, New York 10461
² From the Roche Institute of Molecular Biology, Nutley, New Jersey 07110

Thiostrepton, a peptide antibiotic, is shown to inhibit polypeptide chain initiation in Escherichia coli. The compound, which binds specifically to the 50 S ribosomal subunit, appears to act by preventing the catalytic recycling of initiation factor 2 (IF-2). Hence, when IF-2 functions catalytically, thiostrepton inhibits fMet-tRNA binding to the ribosome; but when IF-2 functions stoichiometrically, thiostrepton is without effect. Furthermore, thiostrepton inhibits the ribosome-dependent hydrolysis of GTP by IF-2 when hydrolysis is tightly coupled to formation of the initiation complex. In contrast, the antiobiotic has no effect on ribosomedependent uncoupled hydrolysis of GTP catalyzed by IF-2. We conclude that thiostrepton inhibits the initiation reaction by blocking the ribosomal site involved in the dissociation of IF-2 from the 70 S initiation complex.

CiteULike    Complore    Connotea    Del.icio.us    Digg    Reddit    Technorati    What's this?