“…In the past years, hybrid quantum mechanics/molecular mechanics (QM/MM) calculations have proved to be very valuable in the study of retaining GTs mechanism (Ardèvol & Rovira, 2011;Bobovská, Tvaroška, & Kóňa, 2014Gómez, Polyak, Thiel, Lluch, & Masgrau, 2012;Gómez et al, 2014;Lira-Navarrete et al, 2014;Rojas-Cervellera, Ardèvol, Boero, Planas, & Rovira, 2013;Trnka, Kozmon, Tsvaroska, & Koca, 2015). Most of the systems for which a crystallographic structure was available have been studied theoretically and much insight has been gained in the description and understanding of how these enzymes catalyze the formation of a new glycosidic bond.…”