Question

a. What acyl group does pyruvate decarboxylase transfer to a proton?

b. What acyl group does the pyruvate dehydrogenase complex transfer to coenzyme A?

c. What acyl group does transketolase transfer to ribose-5-P?

Short answer

The atoms shown in pink are transferred acyl groups.

Step-by-step solution

Pyruvate decarboxylase

Pyruvate decarboxylase is an enzyme that requires TPP to transfer the acyl group of pyruvate to a proton forming acetaldehyde.

Pyruvate dehydrogenase complex

The pyruvate dehydrogenase complex is made of three enzymes and five coenzymes. It transfers the acyl group of pyruvate to acetyl-CoA.

Transketolase

Transketolase transfers an acyl group from xylulose-5-phosphate to ribose-5-phosphate.

Acyl group transfer by pyruvate decarboxylase

The below given pink atoms indicate the acyl group transferred from pyruvate to proton

Acyl group transfer by pyruvate dehydrogenase complex

In the below-given figure, pink box atoms indicate the acyl group transferred from pyruvate to acetyl-CoA.

Acyl group transfer by transketolase

The below given pink box atoms show the acyl group transferred from xylulose-5-phosphate to ribose-5-phosphate.