<prompt> Vitamin B1 is required for which reactionTransaminationOxidative decarboxylationCarboxylationAll of the above  <response>: Ans. is b i.e.,Oxidative decarboxylation Active form coenzyme form of thiamine is thiamine pyrophosphate TPP, also called thiamine diphosphate TDP.TPP acts as coenzyme forOxidative decarboxylation:- Pyruvate dehydrogenase, a-ketoglutarate dehydrogenase, brached-chain keto acid dehydrogenase.Transketolase in PPP. 