Anomeric Selectivity of Trehalose Transferase with Rare l-Sugars.
Mestrom, L., Marsden, S.R., van der Eijk, H., Laustsen, J.U., Jeffries, C.M., Svergun, D.I., Hagedoorn, P.L., Bento, I., Hanefeld, U.(2020) ACS Catal 10: 8835-8839
- PubMed: 32953231 
- DOI: https://doi.org/10.1021/acscatal.0c02117
- Primary Citation of Related Structures:  
6ZJ4, 6ZJ7, 6ZJH, 6ZMZ, 6ZN1 - PubMed Abstract: 
Retaining LeLoir glycosyltransferases catalyze the formation of glycosidic bonds between nucleotide sugar donors and carbohydrate acceptors. The anomeric selectivity of trehalose transferase from Thermoproteus uzoniensis was investigated for both d- and l-glycopyranose acceptors. The enzyme couples a wide range of carbohydrates, yielding trehalose analogues with conversion and enantioselectivity of >98%. The anomeric selectivity inverts from α,α-(1 → 1)-glycosidic bonds for d-glycopyranose acceptors to α,β-(1 → 1)-glycosidic bonds for l-glycopyranose acceptors, while ( S )-selectivity was retained for both types of sugar acceptors. Comparison of protein crystal structures of trehalose transferase in complex with α,α-trehalose and an unnatural α,β-trehalose analogue highlighted the mechanistic rationale for the observed inversion of anomeric selectivity.
Organizational Affiliation: 
Department of Biotechnology, Delft University of Technology, Van der Maasweg 9, 2629 HZ, Delft, The Netherlands.