title: Decreasing the sialidase activity of multifunctional Pasteurella multocida α2-3-sialyltransferase 1 (PmST1) by site-directed mutagenesis.
abstract: Pasteurella multocida α2-3-sialyltransferase 1 (PmST1) is a multifunctional enzyme which has α2-6-sialyltransferase, α2-3-sialidase, and α2-3-trans-sialidase activities in addition to its major α2-3-sialyltransferase activity. The presence of the α2-3-sialidase activity of PmST1 complicates its application in enzymatic synthesis of α2-3-linked sialosides as the product formed can be hydrolyzed by the enzyme. Herein we show that the α2-3-sialidase activity of PmST1 can be significantly decreased by protein crystal structure-based site-directed mutagenesis. A PmST1 double mutant E271F/R313Y showed a significantly (6333-fold) decreased sialidase activity without affecting its α2-3-sialyltransferase activity. The double mutant E271F/R313Y, therefore, is a superior enzyme for enzymatic synthesis of α2-3-linked sialosides.
authors.affiliation: Department of Chemistry, University of California-Davis, One Shields Avenue, Davis, CA 95616, USA.
authors.forename: Go
authors.initials: G
authors.lastname: Sugiarto
authors.forename: Kam
authors.initials: K
authors.lastname: Lau
authors.forename: Yanhong
authors.initials: Y
authors.lastname: Li
authors.forename: Zahra
authors.initials: Z
authors.lastname: Khedri
authors.forename: Hai
authors.initials: H
authors.lastname: Yu
authors.forename: Diem-Thuy
authors.initials: DT
authors.lastname: Le
authors.forename: Xi
authors.initials: X
authors.lastname: Chen
mesh_terms: D001426:Bacterial Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D006868:Hydrolysis; D016297:Mutagenesis, Site-Directed; D009154:Mutation; D009439:Neuraminidase / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D016979:Pasteurella multocida / Q000201:enzymology*; D017510:Protein Folding; D012799:Sialyltransferases / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D013379:Substrate Specificity
chemical_list: D001426:Bacterial Proteins; D012799:Sialyltransferases; D009439:Neuraminidase