An alternative strategy to convert GHs into efficient transglycosylases is to increase the transglycosylation/hydrolysis (T/H) ratio while conserving the retaining mechanism. To achieve this, a considerable number of studies have employed rational or random protein engineering methodologies. However, such approaches require either in-depth structural and biochemical knowledge and, in some cases, use of sophisticated computational methods (rational design); or the creation of large libraries, introducing location-agnostic modifications, coupled with powerful phenotypic screens (random mutagenesis) . Nevertheless, by simply targeting a small number of conserved active-site residues in several retaining GHs , we previously demonstrated that transglycosylation capability can be improved without extensive screening using structural information coupled with sequence conservation analysis. Moreover, others have transposed our obtained beneficial mutations to related enzymes, leading to significant transglycosylation yields .