title: Structural insights into sialic acid enzymology.
abstract: Sialic acids are a diverse family of negatively charged sugars that play essential biological roles. Their presence and relative abundance in different cells is ultimately regulated by the concerted action of a large set of enzymes. In this review, we focus on the most recent advances on the enzymes that govern sialic acid metabolism, with emphasis on structural work. Major progress has been made in dissecting the catalytic mechanism of sialidases, revealing a modified scenario of the typical glycosidase ping-pong mechanism. Similarly, X-ray structures of sialyltransferases uncover significant variations of formerly known glycosyltransferase foldings. Both sialidases and sialyltransferases seem to tell us that sialic acid-handling enzymes have evolved important modifications related to the distinctive features of sialic acid itself.
authors.affiliation: Département de Biologie Structurale & Chimie, Institut Pasteur, 25 rue du Docteur Roux, 75724 Paris, France. alebus@pasteur.edu.uy
authors.forename: Alejandro
authors.initials: A
authors.lastname: Buschiazzo
authors.forename: Pedro M
authors.initials: PM
authors.lastname: Alzari
mesh_terms: D000818:Animals; D006801:Humans; D006899:Mixed Function Oxygenases / Q000737:chemistry* / Q000378:metabolism*; D008958:Models, Molecular; D019158:N-Acetylneuraminic Acid / Q000737:chemistry* / Q000378:metabolism*; D012799:Sialyltransferases / Q000737:chemistry* / Q000378:metabolism*; D013379:Substrate Specificity
chemical_list: D006899:Mixed Function Oxygenases; D012799:Sialyltransferases; D019158:N-Acetylneuraminic Acid