Enzyme glycation influences product yields during oligosaccharide synthesis by reverse hydrolysis

Possible evidence is presented for Maillard glycation of enzymes during oligosaccharide synthesis by reverse hydrolysis. In 70% (w/v) mannose solutions, 1,2-α-mannosidase from Penicillium citrinum lost 40% and α-mannosidase from almonds lost 60% activity at 55 °C over 2 weeks. Oligosaccharide yields were 15 and 45% respectively. Higher molecular weight glycation adducts were formed in a time-dependent manner as seen by MALDI-TOF. Inhibitors of the Maillard reaction were able to partially alleviate these effects resulting in reduced loss of enzyme activity and oligosaccharide yield increases of 27–53% relative to the control.