GLYCATION OF MYOFIBRILLAR PROTEINS AND ATPASE ACTIVITY AFTER INCUBATION WITH 11 SUGARS

Rat skeletal muscle myofibrils were incubated in the presence of D-glu cose, D-fructose, D-galactose, D-ribose, D-tagatose, D-arabinose, D-xy lose, D-mannose, L-sorbose, L-rhamnose or DL-glyceraldehyde and myofib rillar ATPase activity as well as the extent of glycation was measured . The attachment of sugars to proteins during glycation was generally dependent on the percentage of a given sugar present in the open-chain form. Glycation resulted in the decrease of myofibrillar ATPase activ ity. This decrease was low after incubation of myofibrillar proteins w ith slowly glycating sugars (e.g. glucose) and high with fast glycatin g sugars (e.g. ribose or glyceraldehyde). ATPase activity was less red uced in the presence of beta-mercaptoethanol.