1LVA

Crystal structure of a C-terminal fragment of Moorella thermoacetica elongation factor SelB

Summary for 1LVA

• Entry DOI: 10.2210/pdb1lva/pdb
• Descriptor: Selenocysteine-specific elongation factor, YTTRIUM ION, SULFATE ION, ... (4 entities in total)
• Functional Keywords: winged-helix, translation
• Biological source: Moorella thermoacetica
• Cellular location: Cytoplasm: Q46455
• Total number of polymer chains: 1
• Total formula weight: 30011.43

Authors

Selmer, M.,Su, X.-D. (deposition date: 2002-05-28, release date: 2002-08-21, Last modification date: 2024-10-23)

Primary citation

Selmer, M.,Su, X.D.
Crystal structure of an mRNA-binding fragment of Moorella thermoacetica elongation factor SelB.
EMBO J., 21:4145-4153, 2002

PubMed Abstract: SelB 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.

PubMed: 12145214
DOI: 10.1093/emboj/cdf408

Experimental method

X-RAY DIFFRACTION (2.12 Å)