3CB4

The Crystal Structure of LepA

3CB4 の概要

• エントリーDOI: 10.2210/pdb3cb4/pdb
• 分子名称: GTP-binding protein lepA (2 entities in total)
• 機能のキーワード: gtpase, ob-fold, gtp-binding, membrane, nucleotide-binding, translation
• 由来する生物種: Escherichia coli
• 細胞内の位置: Cell inner membrane; Peripheral membrane protein; Cytoplasmic side (Probable): P60785
• タンパク質・核酸の鎖数: 6
• 化学式量合計: 399912.56

構造登録者

Evans, R.N.,Blaha, G.,Bailey, S.,Steitz, T.A. (登録日: 2008-02-21, 公開日: 2008-03-18, 最終更新日: 2024-10-30)

主引用文献

Evans, R.N.,Blaha, G.,Bailey, S.,Steitz, T.A.
The structure of LepA, the ribosomal back translocase.
Proc.Natl.Acad.Sci.Usa, 105:4673-4678, 2008

PubMed Abstract: LepA is a highly conserved elongation factor that promotes the back translocation of tRNAs on the ribosome during the elongation cycle. We have determined the crystal structure of LepA from Escherichia coli at 2.8-A resolution. The high degree of sequence identity between LepA and EF-G is reflected in the structural similarity between the individual homologous domains of LepA and EF-G. However, the orientation of domains III and V in LepA differs from their orientations in EF-G. LepA also contains a C-terminal domain (CTD) not found in EF-G that has a previously unobserved protein fold. The high structural similarity between LepA and EF-G enabled us to derive a homology model for LepA bound to the ribosome using a 7.3-A cryo-EM structure of a complex between EF-G and the 70S ribosome. In this model, the very electrostatically positive CTD of LepA is placed in the direct vicinity of the A site of the large ribosomal subunit, suggesting a possible interaction between the CTD and the back translocated tRNA or 23S rRNA.

PubMed: 18362332
DOI: 10.1073/pnas.0801308105

実験手法

X-RAY DIFFRACTION (2.8 Å)