8SQX

Solution structure of the basal pilin SpaB from Corynebacterium diphtheriae

8SQX の概要

• エントリーDOI: 10.2210/pdb8sqx/pdb
• NMR情報: BMRB: 26336
• 分子名称: Putative surface anchored protein (1 entity in total)
• 機能のキーワード: pilin, basal, minor, isopeptide, cell adhesion
• 由来する生物種: Corynebacterium diphtheriae NCTC 13129
• タンパク質・核酸の鎖数: 1
• 化学式量合計: 13605.12

構造登録者

Sue, C.K.,Mahoney, B.J.,Cheung, N.A.,Clubb, R.T. (登録日: 2023-05-04, 公開日: 2023-06-07, 最終更新日: 2024-05-15)

主引用文献

Sue, C.K.,Cheung, N.A.,Mahoney, B.J.,McConnell, S.A.,Scully, J.M.,Fu, J.Y.,Chang, C.,Ton-That, H.,Loo, J.A.,Clubb, R.T.
The basal and major pilins in the Corynebacterium diphtheriae SpaA pilus adopt similar structures that competitively react with the pilin polymerase.
Biopolymers, 115:e23539-e23539, 2024

PubMed Abstract: Many species of pathogenic gram-positive bacteria display covalently crosslinked protein polymers (called pili or fimbriae) that mediate microbial adhesion to host tissues. These structures are assembled by pilus-specific sortase enzymes that join the pilin components together via lysine-isopeptide bonds. The archetypal SpaA pilus from Corynebacterium diphtheriae is built by the SrtA pilus-specific sortase, which crosslinks lysine residues within the SpaA and SpaB pilins to build the shaft and base of the pilus, respectively. Here, we show that SrtA crosslinks SpaB to SpaA via a K139(SpaB)-T494(SpaA) lysine-isopeptide bond. Despite sharing only limited sequence homology, an NMR structure of SpaB reveals striking similarities with the N-terminal domain of SpaA ( SpaA) that is also crosslinked by SrtA. In particular, both pilins contain similarly positioned reactive lysine residues and adjacent disordered AB loops that are predicted to be involved in the recently proposed "latch" mechanism of isopeptide bond formation. Competition experiments using an inactive SpaB variant and additional NMR studies suggest that SpaB terminates SpaA polymerization by outcompeting SpaA for access to a shared thioester enzyme-substrate reaction intermediate.

PubMed: 37227047
DOI: 10.1002/bip.23539

実験手法

SOLUTION NMR