Affordable Access

Impaired in vitro kinetics of EF-Tu mutant Aa.

Authors
  • Tapio, S
  • Bilgin, N
  • Ehrenberg, M
Type
Published Article
Journal
European journal of biochemistry / FEBS
Publication Date
Mar 10, 1990
Volume
188
Issue
2
Pages
347–354
Identifiers
PMID: 2180702
Source
Medline
License
Unknown

Abstract

The kirromycin-resistant EF-Tu mutant Aa, previously shown to be an antisuppressor for nonsense and missense suppressor tRNAs, has been characterised in a poly(U)-primed translation system in vitro. Two major defects were found in the function of the mutant. First, the dissociation constant for Aa binding to Phe-tRNA(Phe) was increased tenfold compared to wild-type EF-Tu. Second, kcat/Km for the interaction between the EF-Tu.GTP.aa-tRNA complex and the ribosome was decreased by the mutation to one third of its wild-type value. No differences were observed between mutant and wild-type factor in the regeneration of EF-Tu.GTP from EF-Tu.GDP via EF-Ts or in the mistranslation frequency by Leu-tRNA(4Leu). The relation between the in vitro results and the mutant phenotype in vivo is discussed.

Report this publication

Statistics

Seen <100 times