uu.seUppsala University Publications
Change search
ReferencesLink to record
Permanent link

Direct link
A single amino acid substitution in elongation factor Tu disrupts interaction between the ternary complex and the ribosome
Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Molecular Biology.
Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Molecular Biology.
1993 (English)In: Journal of Bacteriology, ISSN 0021-9193, E-ISSN 1098-5530, Vol. 175, no 1, 240-250 p.Article in journal (Refereed) Published
Abstract [en]

Elongation factor Tu (EF-Tu).GTP has the primary function of promoting the efficient and correct interaction of aminoacyl-tRNA with the ribosome. Very little is known about the elements in EF-Tu involved in this interaction. We describe a mutant form of EF-Tu, isolated in Salmonella typhimurium, that causes a severe defect in the interaction of the ternary complex with the ribosome. The mutation causes the substitution of Val for Gly-280 in domain II of EF-Tu. The in vivo growth and translation phenotypes of strains harboring this mutation are indistinguishable from those of strains in which the same tuf gene is insertionally inactivated. Viable cells are not obtained when the other tuf gene is inactivated, showing that the mutant EF-Tu alone cannot support cell growth. We have confirmed, by partial protein sequencing, that the mutant EF-Tu is present in the cells. In vitro analysis of the natural mixture of wild-type and mutant EF-Tu allows us to identify the major defect of this mutant. Our data shows that the EF-Tu is homogeneous and competent with respect to guanine nucleotide binding and exchange, stimulation of nucleotide exchange by EF-Ts, and ternary complex formation with aminoacyl-tRNA. However various measures of translational efficiency show a significant reduction, which is associated with a defective interaction between the ribosome and the mutant EF-Tu.GTP.aminoacyl-tRNA complex. In addition, the antibiotic kirromycin, which blocks translation by binding EF-Tu on the ribosome, fails to do so with this mutant EF-Tu, although it does form a complex with EF-Tu. Our results suggest that this region of domain II in EF-Tu has an important function and influences the binding of the ternary complex to the codon-programmed ribosome during protein synthesis. Models involving either a direct or an indirect effect of the mutation are discussed.

Place, publisher, year, edition, pages
1993. Vol. 175, no 1, 240-250 p.
National Category
Natural Sciences
URN: urn:nbn:se:uu:diva-242597PubMedID: 8416899OAI: oai:DiVA.org:uu-242597DiVA: diva2:784191
Available from: 2015-01-28 Created: 2015-01-28 Last updated: 2015-01-28Bibliographically approved

Open Access in DiVA

No full text


Search in DiVA

By author/editor
Hughes, Diarmaid
By organisation
Department of Molecular Biology
In the same journal
Journal of Bacteriology
Natural Sciences

Search outside of DiVA

GoogleGoogle Scholar

Altmetric score

Total: 392 hits
ReferencesLink to record
Permanent link

Direct link