1,2-alpha-l-Fucosynthase: a glycosynthase derived from an inverting alpha-glycosidase with an unusual reaction mechanism.
Fucosyloligosaccharides have great therapeutic potential. Here we present a new route for synthesizing a Fucalpha1,2Gal linkage by introducing glycosynthase technology into 1,2-alpha-l-fucosidase. The enzyme adopts a unique reaction mechanism, in which asparagine-423 activated by aspartic acid-766 acts as a base while asparagine-421 fixes both a catalytic water and glutamic acid-566 (an acid) in the proper orientations. Glycosynthase activity of N421G, N423G, and D766G mutants was examined using beta-fucosyl fluoride and lactose, and among them, the D766G mutant most effectively synthesized 2'-fucosyllactose. 1,2-alpha-l-Fucosynthase is the first glycosynthase derived from an inverting alpha-glycosidase and from a glycosidase with an unusual reaction mechanism.
Research Institute for Bioresources and Biotechnology, Ishikawa Prefectural University, Nonoichi, Ishikawa 921-8836, Japan.
Jun
J
Wada
Yuji
Y
Honda
Masamichi
M
Nagae
Ryuichi
R
Kato
Soichi
S
Wakatsuki
Takane
T
Katayama
Hajime
H
Taniguchi
Hidehiko
H
Kumagai
Motomitsu
M
Kitaoka
Kenji
K
Yamamoto
D001426:Bacterial Proteins / Q000096:biosynthesis / Q000737:chemistry* / Q000235:genetics; D001644:Bifidobacterium / Q000201:enzymology; D002384:Catalysis; D006868:Hydrolysis; D016297:Mutagenesis, Site-Directed; D009154:Mutation; D011487:Protein Conformation; D014312:Trisaccharides / Q000096:biosynthesis*; D005644:alpha-L-Fucosidase / Q000096:biosynthesis / Q000737:chemistry* / Q000235:genetics
D001426:Bacterial Proteins; D014312:Trisaccharides; D005644:alpha-L-Fucosidase; C031420:2'-fucosyllactose