Crystal structures of nucleotide exchange intermediates in the eEF1A-eEF1B[alpha] complex

• Published in: Nature structural & molecular biology Vol. 8; no. 6; p. 531
• Main Authors: Gregers Rom Andersen, Valente, Louis, Pedersen, Lise, Terri Goss Kinzy, Nyborg, Jens
• Format: Journal Article
• Language: English
• Published: New YOrk Nature Publishing Group 01.06.2001
• Subjects: Biosynthesis
• ISSN: 1545-9993; 1545-9985
• DOI: 10.1038/88598

In the elongation cycle of protein biosynthesis, the nucleotide exchange factor eEF1Bα catalyzes the exchange of GDP bound to the G-protein, eEF1A, for GTP. To obtain more information about the recently solved eEF1A-eEF1Bα structure, we determined the structures of the eEF1A-eEF1Bα-GDP-Mg2+ , eEF1A-eEF1Bα-GDP and eEF1A-eEF1Bα-GDPNP complexes at 3.0, 2.4 and 2.05 Å resolution, respectively. Minor changes, specifically around the nucleotide binding site, in eEF1A and eEF1Bα are consistent with in vivo data. The base, sugar and α-phosphate bind as in other known nucleotide G-protein complexes, whereas the β- and γ-phosphates are disordered. A mutation of Lys 205 in eEF1Bα that inserts into the Mg2+ binding site of eEF1A is lethal. This together with the structures emphasizes the essential role of Mg2+ in nucleotide exchange in the eEF1A-eEF1Bα complex.