5EOV

C-terminal domain of the 16S/23S rRNA (cytidine-2'-O)-methyltransferase TlyA.

5EOV の概要

• エントリーDOI: 10.2210/pdb5eov/pdb
• 分子名称: 16S/23S rRNA (cytidine-2'-O)-methyltransferase TlyA (2 entities in total)
• 機能のキーワード: methyltransferase, ribosome, antibiotic sensitivity, transferase
• 由来する生物種: Mycobacterium tuberculosis
• タンパク質・核酸の鎖数: 1
• 化学式量合計: 23089.35

構造登録者

Witek, M.A.,Conn, G.L. (登録日: 2015-11-10, 公開日: 2016-11-23, 最終更新日: 2023-09-27)

主引用文献

Witek, M.A.,Kuiper, E.G.,Minten, E.,Crispell, E.K.,Conn, G.L.
A Novel Motif for S-Adenosyl-l-methionine Binding by the Ribosomal RNA Methyltransferase TlyA from Mycobacterium tuberculosis.
J. Biol. Chem., 292:1977-1987, 2017

PubMed Abstract: Capreomycin is a potent ribosome-targeting antibiotic that is an essential component of current antituberculosis treatments, particularly in the case of multidrug-resistant Mycobacterium tuberculosis (Mtb). Optimal capreomycin binding and Mtb ribosome inhibition requires ribosomal RNA methylation in both ribosome subunits by TlyA (Rv1694), an enzyme with dual 2'-O-methytransferase and putative hemolytic activities. Despite the important role of TlyA in capreomycin sensitivity and identification of inactivating mutations in the corresponding Mtb gene tlyA, which cause resistance to capreomycin, our current structural and mechanistic understanding of TlyA action remains limited. Here, we present structural and functional analyses of Mtb TlyA interaction with its obligatory co-substrate for methyltransferase activity, S-adenosyl-l-methionine (SAM). Despite adopting a complete class I methyltransferase fold containing conserved SAM-binding and catalytic motifs, the isolated TlyA carboxyl-terminal domain exhibits no detectable affinity for SAM. Further analyses identify a tetrapeptide motif (RXWV) in the TlyA interdomain linker as indispensable for co-substrate binding. Our results also suggest that structural plasticity of the RXWV motif could contribute to TlyA domain interactions, as well as specific recognition of its two structurally distinct ribosomal RNA targets. Our findings thus reveal a novel motif requirement for SAM binding by TlyA and set the stage for future mechanistic studies of TlyA substrate recognition and modification that underpin Mtb sensitivity to capreomycin.

PubMed: 28031456
DOI: 10.1074/jbc.M116.752659

実験手法

X-RAY DIFFRACTION (1.701 Å)