1lva
From Proteopedia
Crystal structure of a C-terminal fragment of Moorella thermoacetica elongation factor SelB
Structural highlights
FunctionSELB_MOOTH Translation factor necessary for the incorporation of selenocysteine into proteins. It probably replaces EF-Tu for the insertion of selenocysteine directed by the UGA codon. SelB binds GTP and GDP. Evolutionary ConservationCheck, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf. Publication Abstract from PubMedSelB is an elongation factor needed for the co-translational incorporation of selenocysteine. Selenocysteine is coded by a UGA stop codon in combination with a specific downstream mRNA hairpin. In bacteria, the C-terminal part of SelB recognizes this hairpin, while the N-terminal part binds GTP and tRNA in analogy with elongation factor Tu (EF-Tu). We present the crystal structure of a C-terminal fragment of SelB (SelB-C) from Moorella thermoacetica at 2.12 A resolution, solved by a combination of selenium and yttrium multiwavelength anomalous dispersion. This 264 amino acid fragment contains the entire C-terminal extension beginning after the EF-Tu-homologous domains. SelB-C consists of four similar winged-helix domains arranged into the shape of an L. This is the first example of winged-helix domains involved in RNA binding. The location of conserved basic amino acids, together with data from the literature, define the position of the mRNA-binding site. Steric requirements indicate that a conformational change may occur upon ribosome interaction. Structural observations and data in the literature suggest that this change happens upon mRNA binding. Crystal structure of an mRNA-binding fragment of Moorella thermoacetica elongation factor SelB.,Selmer M, Su XD EMBO J. 2002 Aug 1;21(15):4145-53. PMID:12145214[1] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
|