From β‐glucanase to β‐glucansynthase: glycosyl transfer to α‐glycosyl fluorides catalyzed by a mutant endoglucanase lacking its catalytic nucleophile

FEBS Letters

Planas, Antoni¹  Malet, Carles¹ 

[1] Laboratory of Biochemistry, Institut Quı́mic de Sarrià, Universitat Ramon Llull, Via Augusta 390, 08017 Barcelona, Spain

关键词: Glycosynthase;    Enzymatic glycosylation;    β-Glucanase;    Glycosyl fluoride;    Nucleophile residue;    1;    3-1;    4-β-glucanase;    1;    3-1;    4-β-d-glucan 4-glucanohydrolase;    MU;    4-methylumbelliferyl;    MALDI-TOF;    matrix-assisted laser desorption ionization time of flight;    MES;    2-[N-morpholino]ethanesulfonic acid;    TES;    N-tris[hydroxymethyl]methyl-2-aminoethanesulfonic acid;   

DOI  :  10.1016/S0014-5793(98)01448-3

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

Removal of the catalytic nucleophile Glu134 of the retaining 1,3-1,4-β-glucanase from Bacillus licheniformis by mutation to alanine yields an enzyme with no glycosidase activity. The mutant is able to catalyze the regio- and stereospecific glycosylation of α-laminaribiosyl fluoride with different glucoside acceptors through a single-step inverting mechanism. The main advantage of the mutant as glycosylation catalyst with respect to the kinetically controlled transglycosylation using the wild-type enzyme is that the reaction products cannot be hydrolyzed by the mutant enzyme, and glycosylation yields rise to 90%.

【 授权许可】

Unknown