Elongation factor Ts can act as a steric chaperone by increasing the solubility of nucleotide binding-impaired elongation factor-Tu.
Several elongation factor (EF) Tu mutants (T25A, H22Y/T25S, D80N, D138N) that have impaired nucleotide binding show decreased solubility on overexpression in the E. coli cell, an indication that they do not fold correctly. Moreover, EF-Tu[T25A] and EF-Tu[D80N] were shown to inhibit cell growth on expression, an effect attributed to their sequestration of EF-Ts [Krab, I. M., and Parmeggiani, A. (1999) J. Biol. Chem. 274, 11132--11138; Krab, I. M., and Parmeggiani, A. (1999) Biochemistry 38, 13035--13041]. We present here results showing that the co-overexpression of EF-Ts at a 1:1 ratio dramatically improves the solubility of mutant EF-Tu, although in the case of EF-Tu[D138N]--which cannot at all bind the nucleotides available in the cell--this is a slow process. Moreover, with co-overexpression of EF-Ts, the mentioned growth inhibition is relieved. We conclude that for the formation of a correct EF-Tu structure the nucleotide plays an important role as a "folding nucleus", and also that in its absence EF-Ts can act as a folding template or steric chaperone for the correct folding of EF-Tu.[1]References
- Elongation factor Ts can act as a steric chaperone by increasing the solubility of nucleotide binding-impaired elongation factor-Tu. Krab, I.M., te Biesebeke, R., Bernardi, A., Parmeggiani, A. Biochemistry (2001) [Pubmed]
Annotations and hyperlinks in this abstract are from individual authors of WikiGenes or automatically generated by the WikiGenes Data Mining Engine. The abstract is from MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.About WikiGenesOpen Access LicencePrivacy PolicyTerms of Useapsburg
