3DMF

T. Thermophilus 16S rRNA N2 G1207 methyltransferase (RsmC) in complex with AdoMet

3DMF の概要

• エントリーDOI: 10.2210/pdb3dmf/pdb
• 関連するPDBエントリー: 3DMG 3DMH
• 分子名称: Probable ribosomal RNA small subunit methyltransferase, SULFATE ION, S-ADENOSYLMETHIONINE, ... (4 entities in total)
• 機能のキーワード: monomethyltranserase, 16s rrna methyltransferase, g1207 methyltransferase, s-adenosyl-l-methionine, translation, transferase
• 由来する生物種: Thermus thermophilus
• タンパク質・核酸の鎖数: 1
• 化学式量合計: 42512.60

構造登録者

Demirci, H.,Gregory, S.T.,Dahlberg, A.E.,Jogl, G. (登録日: 2008-07-01, 公開日: 2008-07-29, 最終更新日: 2024-02-21)

主引用文献

Demirci, H.,Gregory, S.T.,Dahlberg, A.E.,Jogl, G.
Crystal Structure of the Thermus thermophilus 16 S rRNA Methyltransferase RsmC in Complex with Cofactor and Substrate Guanosine.
J.Biol.Chem., 283:26548-26556, 2008

PubMed Abstract: Post-transcriptional modification is a ubiquitous feature of ribosomal RNA in all kingdoms of life. Modified nucleotides are generally clustered in functionally important regions of the ribosome, but the functional contribution to protein synthesis is not well understood. Here we describe high resolution crystal structures for the N(2)-guanine methyltransferase RsmC that modifies residue G1207 in 16 S rRNA near the decoding site of the 30 S ribosomal subunit. RsmC is a class I S-adenosyl-L-methionine-dependent methyltransferase composed of two methyltransferase domains. However, only one S-adenosyl-L-methionine molecule and one substrate molecule, guanosine, bind in the ternary complex. The N-terminal domain does not bind any cofactor. Two structures with bound S-adenosyl-L-methionine and S-adenosyl-L-homocysteine confirm that the cofactor binding mode is highly similar to other class I methyltransferases. Secondary structure elements of the N-terminal domain contribute to cofactor-binding interactions and restrict access to the cofactor-binding site. The orientation of guanosine in the active site reveals that G1207 has to disengage from its Watson-Crick base pairing interaction with C1051 in the 16 S rRNA and flip out into the active site prior to its modification. Inspection of the 30 S crystal structure indicates that access to G1207 by RsmC is incompatible with the native subunit structure, consistent with previous suggestions that this enzyme recognizes a subunit assembly intermediate.

PubMed: 18667428
DOI: 10.1074/jbc.M804005200

実験手法

X-RAY DIFFRACTION (1.58 Å)