In the reaction below, catalyzed by transketolase, what is compound Z? Z + ribose-5-P glyceraldehyde-3-P + sedoheptulose-7-P

Question

In the reaction below, catalyzed by transketolase, what is compound Z? Z + ribose-5-P <--> glyceraldehyde-3-P + sedoheptulose-7-P

Quizplus · Accepted Answer

According to the reaction, Z must be xylulose 5-phosphate. This is because transketolase catalyzes the transfer of a two-carbon unit from Z to ribose-5-P to form glyceraldehyde-3-P and sedoheptulose-7-P. Xylulose 5-phosphate is a five-carbon sugar-phosphate that can donate a two-carbon unit and still leave a three-carbon sugar-phosphate (glyceraldehyde-3-P) and a seven-carbon sugar-phosphate (sedoheptulose-7-P). None of the other choices fit this description.

In the Reaction Below, Catalyzed by Transketolase, What Is Compound