2vw1

Crystal structure of the NanB sialidase from Streptococcus pneumoniae

spinqualitylabelsall models 2vw1, resolution 2.39Å Show:Asymmetric Unit Biological Assembly Drag the structure with the mouse to rotate   Export Animated Image   Print3D Structural highlights 2vw1 is a 1 chain structure with sequence from Streptococcus pneumoniae. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance. Method: X-ray diffraction, Resolution 2.39Å Ligands: DAN, GOL Resources: FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT Function NANB_STRPN Evolutionary Conservation Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf. Publication Abstract from PubMed The Streptococcus pneumoniae genomes encode up to three sialidases (or neuraminidases), NanA, NanB and NanC, which are believed to be involved in removing sialic acid from host cell surface glycans, thereby promoting colonization of the upper respiratory tract. Here, we present the crystal structure of NanB to 1.7 A resolution derived from a crystal grown in the presence of the buffer Ches (2-N-cyclohexylaminoethanesulfonic acid). Serendipitously, Ches was found bound to NanB at the enzyme active site, and was found to inhibit NanB with a K(i) of approximately 0.5 mM. In addition, we present the structure to 2.4 A resolution of NanB in complex with the transition-state analogue Neu5Ac2en (2-deoxy-2,3-dehydro-N-acetyl neuraminic acid), which inhibits NanB with a K(i) of approximately 0.3 mM. The sulphonic acid group of Ches and carboxylic acid group of Neu5Ac2en interact with the arginine triad of the active site. The cyclohexyl group of Ches binds in the hydrophobic pocket of NanB occupied by the acetamidomethyl group of Neu5Ac2en. The topology around the NanB active site suggests that the enzyme would have a preference for alpha2,3-linked sialoglycoconjugates, which is confirmed by a kinetic analysis of substrate binding. NMR studies also confirm this preference and show that, like the leech sialidase, NanB acts as an intramolecular trans-sialidase releasing Neu2,7-anhydro5Ac. All three pneumoccocal sialidases possess a carbohydrate-binding domain that is predicted to bind sialic acid. These studies provide support for a possible differential role for NanB compared to NanA in pneumococcal virulence. Crystal structure of the NanB sialidase from Streptococcus pneumoniae.,Xu G, Potter JA, Russell RJ, Oggioni MR, Andrew PW, Taylor GL J Mol Biol. 2008 Dec 12;384(2):436-49. Epub 2008 Sep 21. PMID:18835278 From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See Also Neuraminidase 3D structures

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