8IQ9
Crystal structure of trimeric K2-2 TSP in complex with tetrasaccharide and octasaccharide
Summary for 8IQ9
| Entry DOI | 10.2210/pdb8iq9/pdb |
| Descriptor | 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) |
| Functional Keywords | bacteriophage, tailspike protein, klebsiella pneumoniae k2, hydrolase |
| Biological source | Klebsiella phage VLC6 |
| Total number of polymer chains | 3 |
| Total formula weight | 200376.29 |
| Authors | Ye, T.J.,Ko, T.P.,Huang, K.F.,Wu, S.H. (deposition date: 2023-03-16, release date: 2024-02-21, Last modification date: 2024-04-03) |
| Primary citation | 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 Cited by 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: 38349137DOI: 10.1128/mbio.03519-23 PDB entries with the same primary citation |
| Experimental method | X-RAY DIFFRACTION (1.58 Å) |
Structure validation
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