Selective manipulation of steroid hydroxyl groups with boronate esters: efficient access to antigenic C-3 linked steroid-protein conjugates and steroid sulfate standards for drug detection

摘要

Cloning of E. coli K-12 orf 8 (wbbI) and over-expression of the corresponding enzyme as a maltose-binding fusion protein provided recombinant WbbI β-1,6-galactofuranosyltransferase activity. Challenged with synthetic acceptor analogues in the presence of UDP-galactofuranose as a donor, WbbI showed a modest preference for pyranoside acceptor substrates of the α-D-gluco-configuration but it also possessed the ability to turn-over acceptor analogues.