Recently a novel phosphorylase was found in the human gut microbe Bacteroides thetaiotaomicron that is able to degrade complex human N-glycans. This phosphorylase is capable of phosphorolysis of the D-Man-b-1,4-D-GlcNAc released by hydrolysis of
N-linked glycans. This core linkage is difficult to synthesise and thus this enzyme may prove valuable in the synthesis of N-glycan core structures, particularly as it is able to transfer Man onto GlcNAc-b-1,4-GlcNAc.