VPY-0055
QUESTION
The activity of which enzyme below in the HMF shunt would be non-affected by thiamin deficiency?
OPTIONS
(A) Glucose 6-phosphate dehydrogenase
(B) 6-phosphogIucanate dehydrogenase
(C) Transketolase
(D) Tansaldolase
ANSWER
(C) Transketolase
EXPLANATION
Transketolase is the correct option because transketolase requires thiamine pyrophosphate (TPP), a thiamin-derived coenzyme, and therefore its activity is affected by thiamin deficiency. Glucose-6-phosphate dehydrogenase, 6-phosphogluconate dehydrogenase and transaldolase do not require TPP as their essential coenzyme in the pentose phosphate pathway.