Novel triple mutant of an extremophilic glycosyl hydrolase enables the rapid synthesis of thioglycosides.

In order to expand the toolbox of enzymes available for thioglycoside synthesis, we describe here the first example of an extremophilic glycosyl hydrolase from Halothermothrix orenii ( Hor GH1) engineered towards thioglycosynthase activity with a novel combination of mutations. Using the triple mutant, Hor GH1 M299R/E166A/E354G, a range of thioglycosides from glycosyl fluoride donors and aromatic thiols could be synthesised with exquisite stereoselectivity and good to excellent conversions (61-93%).