8IQ9

Crystal structure of trimeric K2-2 TSP in complex with tetrasaccharide and octasaccharide

8IQ9 の概要

• エントリーDOI: 10.2210/pdb8iq9/pdb
• 分子名称: K2-2 TSP, alpha-D-glucopyranuronic acid-(1-3)-beta-D-mannopyranose-(1-4)-alpha-D-glucopyranose-(1-3)-beta-D-glucopyranose-(1-4)-[alpha-D-glucopyranuronic acid-(1-3)]beta-D-mannopyranose-(1-4)-alpha-D-glucopyranose-(1-3)-beta-D-glucopyranose, alpha-D-glucopyranuronic acid-(1-3)-beta-D-mannopyranose-(1-4)-alpha-D-glucopyranose-(1-3)-beta-D-glucopyranose, ... (6 entities in total)
• 機能のキーワード: bacteriophage, tailspike protein, klebsiella pneumoniae k2, hydrolase
• 由来する生物種: Klebsiella phage VLC6
• タンパク質・核酸の鎖数: 3
• 化学式量合計: 200376.29

構造登録者

Ye, T.J.,Ko, T.P.,Huang, K.F.,Wu, S.H. (登録日: 2023-03-16, 公開日: 2024-02-21, 最終更新日: 2024-04-03)

主引用文献

Ye, T.J.,Fung, K.M.,Lee, I.M.,Ko, T.P.,Lin, C.Y.,Wong, C.L.,Tu, I.F.,Huang, T.Y.,Yang, F.L.,Chang, Y.P.,Wang, J.T.,Lin, T.L.,Huang, K.F.,Wu, S.H.
Klebsiella pneumoniae K2 capsular polysaccharide degradation by a bacteriophage depolymerase does not require trimer formation.
Mbio, 15:e0351923-e0351923, 2024

PubMed Abstract: K2-capsular is a hypervirulent pathogen that causes fatal infections. Here, we describe a phage tailspike protein, named K2-2, that specifically depolymerizes the K2 capsular polysaccharide (CPS) of into tetrasaccharide repeating units. Nearly half of the products contained -acetylation, which was thought crucial to the immunogenicity of CPS. The product-bound structures of this trimeric enzyme revealed intersubunit carbohydrate-binding grooves, each accommodating three tetrasaccharide units of K2 CPS. The catalytic residues and the key interactions responsible for K2 CPS recognition were identified and verified by site-directed mutagenesis. Further biophysical and functional characterization, along with the structure of a tetrameric form of K2-2, demonstrated that the formation of intersubunit catalytic center does not require trimerization, which could be nearly completely disrupted by a single-residue mutation in the C-terminal domain. Our findings regarding the assembly and catalysis of K2-2 provide cues for the development of glycoconjugate vaccines against infection.

PubMed: 38349137
DOI: 10.1128/mbio.03519-23

実験手法

X-RAY DIFFRACTION (1.58 Å)