2lkd
From Proteopedia
IF2-G2 GDP complex
Structural highlights
FunctionIF2_GEOSE One of the essential components for the initiation of protein synthesis. Protects formylmethionyl-tRNA from spontaneous hydrolysis and promotes its binding to the 30S ribosomal subunits. Also involved in the hydrolysis of GTP during the formation of the 70S ribosomal complex. Publication Abstract from PubMedBacterial translation initiation factor IF2 promotes ribosomal subunit association, recruitment, and binding of fMet-tRNA to the ribosomal P-site and initiation dipeptide formation. Here, we present the solution structures of GDP-bound and apo-IF2-G2 of Bacillus stearothermophilus and provide evidence that this isolated domain binds the 50 S ribosomal subunit and hydrolyzes GTP. Differences between the free and GDP-bound structures of IF2-G2 suggest that domain reorganization within the G2-G3-C1 regions underlies the different structural requirements of IF2 during the initiation process. However, these structural signals are unlikely forwarded from IF2-G2 to the C-terminal fMet-tRNA binding domain (IF2-C2) because the connected IF2-C1 and IF2-C2 modules show completely independent mobility, indicating that the bacterial interdomain connector lacks the rigidity that was found in the archaeal IF2 homolog aIF5B. Structural Dynamics of Bacterial Translation Initiation Factor IF2.,Wienk H, Tishchenko E, Belardinelli R, Tomaselli S, Dongre R, Spurio R, Folkers GE, Gualerzi CO, Boelens R J Biol Chem. 2012 Mar 30;287(14):10922-32. Epub 2012 Feb 3. PMID:22308033[1] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. References
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