Reference no: EM13167348

Many carbohydrate linkages are cleaved by hydrolytic enzymes, which is different from glycogen phosphorylase that uses phosphorolysis. There are two acceptable mechanisms for hydrolysis of the glycosidic bonds. Diagram one carbohydrate hydrolysis mechanism in your example. This means electron pushing arrows and labeling structures with appropriate hydroxyls, oxygens and charges if necessary. Carbons and aliphatic hydrogens can be inferred.

For example, you could use the 1-6 glucosidase reaction of debranching ezyme or the glycosidase hydrolase reaction of lysozyme.
First, show the carbohydrate substrate that is at least 2 subunits long. It does not have to be branched, but you must show linkages correctly bonded with the appropriate hydroxyl groups. Then diagram the carbohydrate hydrolysis mechanism.

Second, show a detailed reaction mechanism (like we did with glycogen phosphorylase in class) with electron pushing. Hint, the enzyme has two active site amino acid sidechains, which participate in acid / base catalysis that facilitate the reaction. One mechanism uses one active site amino acid side chain, while the second mechanism uses both active site sidechains. Either mechanism is acceptable.

Label the acid/base or nucleophile / electrophile or any combination in your diagram. Explicitly draw the reaction intermediate.
Finally, draw the products.

2. Thinking about the net energetic output from glycolysis, why is it advantageous to break down glycogen by phosphorolysis instead of hydrolysis? Be quantitative in your argument.