title: Structural and functional studies of Streptococcus pneumoniae neuraminidase B: An intramolecular trans-sialidase.
abstract: The human pathogen Streptococcus pneumoniae expresses neuraminidase proteins that cleave sialic acids from complex carbohydrates. The pneumococcus genome encodes up to three neuraminidase proteins that have been shown to be important virulence factors. Here, we report the first structure of a neuraminidase from S. pneumoniae: the crystal structure of NanB in complex with its reaction product 2,7-anhydro-Neu5Ac. Our structural data, together with biochemical analysis, establish NanB as an intramolecular trans-sialidase with strict specificity towards alpha2-3 linked sialic acid substrates. In addition, we show that NanB differs in its substrate specificity from the other pneumococcal neuraminidase NanA.
authors.affiliation: MRC France, BM14 c/o ESRF, 6 rue Jules Horowitz, BP220, 38043 Grenoble, France.
authors.forename: Heinz
authors.initials: H
authors.lastname: Gut
authors.forename: Samantha J
authors.initials: SJ
authors.lastname: King
authors.forename: Martin A
authors.initials: MA
authors.lastname: Walsh
mesh_terms: D000595:Amino Acid Sequence; D018360:Crystallography, X-Ray; D006023:Glycoproteins / Q000737:chemistry* / Q000378:metabolism; D019158:N-Acetylneuraminic Acid / Q000031:analogs & derivatives / Q000737:chemistry / Q000378:metabolism; D009439:Neuraminidase / Q000737:chemistry* / Q000378:metabolism; D011487:Protein Conformation; D013296:Streptococcus pneumoniae / Q000201:enzymology*
chemical_list: D006023:Glycoproteins; C045712:2,7-anhydro-N-acetylneuraminic acid; C069715:trans-sialidase; D009439:Neuraminidase; D019158:N-Acetylneuraminic Acid