Question

Glucose is phosphorylated to Glucose-6-Phosphate by the enzyme Glucokinase using a molecule of ATP. To which category of enzymes does the Glucokinase belong?

• A. Oxidoreductase.
• B. Hydrolase.
• C. Transferase.
• D. Ligase.

Hint:

Glucokinase transfers a phosphate group from ATP to glucose, so it is a transferase.

Answer 1

The Correct Option is C

Step 1: Understanding the Concept
Enzymes are grouped by the reaction they catalyse. Enzymes that move a functional group from one molecule to another are transferases.

Step 2: Apply to glucokinase
Glucokinase moves the terminal phosphate group of ATP onto C-6 of glucose:
\(\text{glucose} + \text{ATP} \rightarrow \text{glucose-6-phosphate} + \text{ADP}\)

Step 3: Conclusion
This is group transfer, not oxidation-reduction, hydrolysis or joining of molecules, so glucokinase is a transferase.

Final Answer:
Glucokinase is a transferase. \[ \boxed{\text{(C) }\text{Transferase.}} \]