Phenylalanine is degraded into: (A) Fumarate and succinate, (B) Fumarate and acetoacetate, (C) Fumarate and Malate, (D) Fumarate and pyruvate
Answer is B. Phenylalanine is first conveed to tyrosine (For Subsequent metabolism of phenylalanine and tyrosine See att. Treasure. Hereditary tyrosinemia type I (Hepatorenal tyrosinemia) is due to deficiency of the enzyme fumaryl acetoacetate hydrolase (fumarylacetoacetase). Remember the enzyme deficiency - fumarylacetoacetase. That will help you to remember the end products - Fumarate and acetoacetate. Phenylalanine & tyrosine are both glucogenic and ketogenic. Fumarate is glucogenic while acetoacetate is ketogenic.