Interaction of EF-Tu with EF-Ts: substitution of His-118 in EF-Tu destabilizes the EF-Tu x EF-Ts complex but does not prevent EF-Ts from stimulating the release of EF-Tu-bound GDP.
Elongation factor Tu from Escherichia coli with His-118 substituted by glycine (EF-TuH118G) was found to be defective in complex formation with EF-Ts. EF-Ts in excess failed to dissociate kirromycin from the EF-TuH118G x kirromycin complex and to form a stable complex with EF-TuH118G on column chromatography. However, the stimulatory effect of EF-Ts on GDP dissociation from EF-TuH118G x GDP and on poly(U)-directed poly(Phe) synthesis catalyzed by EF-TuH118G was only partially influenced. These results indicate that His-118, while very important for the formation of a stable EF-Tu-EF-Ts complex, is not essential for the transmission of the EF-Ts-dependent signal accelerating the release of the EF-Tu-bound GDP.
Jonák
J
J
Institute of Molecular Genetics, Academy of Sciences of the Czech Republic, Prague. jjon@img.cas.cz
Anborgh
P H
PH
Parmeggiani
A
A
D019943:Amino Acid Substitution; D000900:Anti-Bacterial Agents / Q000378:metabolism; D001665:Binding Sites; D001667:Binding, Competitive; D002852:Chromatography, Ion Exchange; D003001:Cloning, Molecular; D004355:Drug Stability; D004926:Escherichia coli; D005998:Glycine; D006153:Guanosine Diphosphate / Q000378:metabolism*; D006639:Histidine; D007700:Kinetics; D010444:Peptide Elongation Factor Tu / Q000737:chemistry / Q000378:metabolism*; D010445:Peptide Elongation Factors / Q000378:metabolism*; D011728:Pyridones / Q000378:metabolism; D011994:Recombinant Proteins / Q000737:chemistry / Q000378:metabolism; D013816:Thermodynamics
D000900:Anti-Bacterial Agents; D010445:Peptide Elongation Factors; D011728:Pyridones; D011994:Recombinant Proteins; C036506:elongation factor T; D006153:Guanosine Diphosphate; D006639:Histidine; D010444:Peptide Elongation Factor Tu; C008536:mocimycin; D005998:Glycine