Question

which nucleoside is the one most commonly found as part of coenzymes

Answer 1

example is thiamine pyrophosphate (TPP), which is tightly bound in transketolase or pyruvate decarboxylase, while it is less tightly bound in pyruvate dehydrogenase. Other coenzymes, flavin adenine dinucleotide (FAD), biotin, and lipoamide, for instance, are tightly bound.