Which one of the following enzymes use NADP as coenzyme?
## **Core Concept**
The question tests knowledge of biochemical pathways and the specific coenzymes they utilize. NADP (Nicotinamide adenine dinucleotide phosphate) is a coenzyme used in various anabolic reactions, such as lipid and nucleic acid synthesis, and in antioxidant defenses. Enzymes that use NADP as a coenzyme are typically involved in reductive biosynthesis.
## **Why the Correct Answer is Right**
The correct answer, , refers to Glucose-6-phosphate dehydrogenase. This enzyme is a key regulatory enzyme in the pentose phosphate pathway, which generates NADPH (the reduced form of NADP) and pentoses from glucose-6-phosphate. NADPH is crucial for biosynthetic reactions, including fatty acid synthesis, cholesterol synthesis, and as a reducing agent in antioxidant defenses. Glucose-6-phosphate dehydrogenase specifically uses NADP+ as a coenzyme, converting it to NADPH.
## **Why Each Wrong Option is Incorrect**
- **Option A:** - This option does not directly relate to an enzyme known for using NADP as a coenzyme in a well-known metabolic pathway.
- **Option B:** - Similarly, this option does not specify an enzyme directly associated with NADP usage.
- **Option D:** - This option also does not directly correspond to an enzyme known for utilizing NADP.
## **Clinical Pearl / High-Yield Fact**
A critical point to remember is that deficiencies in glucose-6-phosphate dehydrogenase (G6PD) can lead to hemolytic anemia due to the reduced ability of red blood cells to protect themselves against oxidative damage, highlighting the importance of NADPH in cellular protection mechanisms.
## **Correct Answer:** . Glucose-6-phosphate dehydrogenase.