1G7R

X-RAY STRUCTURE OF TRANSLATION INITIATION FACTOR IF2/EIF5B

Summary for 1G7R

• Entry DOI: 10.2210/pdb1g7r/pdb
• Related: 1G7S 1G7T
• Descriptor: TRANSLATION INITIATION FACTOR IF2/EIF5B (2 entities in total)
• Functional Keywords: translational gtpase, translation
• Biological source: Methanothermobacter thermautotrophicus
• Total number of polymer chains: 1
• Total formula weight: 67231.41

Authors

Roll-Mecak, A.,Cao, C.,Dever, T.E.,Burley, S.K. (deposition date: 2000-11-14, release date: 2000-12-06, Last modification date: 2021-02-03)

Primary citation

Roll-Mecak, A.,Cao, C.,Dever, T.E.,Burley, S.K.
X-Ray structures of the universal translation initiation factor IF2/eIF5B: conformational changes on GDP and GTP binding.
Cell(Cambridge,Mass.), 103:781-792, 2000

PubMed Abstract: X-ray structures of the universal translation initiation factor IF2/eIF5B have been determined in three states: free enzyme, inactive IF2/eIF5B.GDP, and active IF2/eIF5B.GTP. The "chalice-shaped" enzyme is a GTPase that facilitates ribosomal subunit joining and Met-tRNA(i) binding to ribosomes in all three kingdoms of life. The conserved core of IF2/eIF5B consists of an N-terminal G domain (I) plus an EF-Tu-type beta barrel (II), followed by a novel alpha/beta/alpha-sandwich (III) connected via an alpha helix to a second EF-Tu-type beta barrel (IV). Structural comparisons reveal a molecular lever, which amplifies a modest conformational change in the Switch 2 region of the G domain induced by Mg(2+)/GTP binding over a distance of 90 A from the G domain active center to domain IV. Mechanisms of GTPase function and ribosome binding are discussed.

PubMed: 11114334
DOI: 10.1016/S0092-8674(00)00181-1

Experimental method

X-RAY DIFFRACTION (2.2 Å)