<prompt> A bodybuilder starts eating raw egg for protein. He used develop fatigue on moderate exercise. The doctor prescribes a vitamin. Which enzyme is deficient in him?Glucose 6 PhosphatasePyruvate CarboxylasePEPCKGlycogen Phosphorylase  <response>: Ans. b Pyruvate CarboxylaseRef: Harpers Biochemistry 30th Ed; Page No- 560 Raw egg contains Avidin, it is antagonist of Biotin. Eating raw egg is harmful because of Avidin present in raw egg inhibit biotin. Affinity of Avidin to Biotin is stronger than most of the Antigen antibody reaction. So doctor only prescribe Biotin. ELISA test and Labeling of DNA test are used. Why do u need biotin? Because biotin is the mother of all carboxylation reaction. Only one carboxylase given in options, so option B will be the best answer.Note Streptavidin is also biotin antagonist. It is purified from Streptomyces Avidin. Bind 4 molecule of biotin.Coenzyme role of BiotinBiotin dependent carboxylation reaction Pyruvate carboxylase: pyruvate 3C- oxaloacetate 4C Acetyl-CoA carboxylase: acetyl-CoA 2C- malonyl-CoA 3C Propionyl-CoA carboxylase: propionyl-CoA3C- methylmalonyl-CoA4C Methyl Crotonyl CoA Carboxylase.Biotin Independent carboxylation reaction Malic enzyme Pyruvate to Malate Carbamoyl phosphate Synthetases -I II Gamma Carboxylation Vitamin K dependent Addition of CO2 tC6 in purine ring AIR CarboxylaseExtra MileCoenzyme Role of Vitamin B complex Thiamine Pyruvate dehydrogenase links glycolysis to TCA cycle a-ketoglutarate dehydrogenase TCA cycle Transketolase HMP shunt Branched-chain ketoacid dehydrogenaseRiboflavin Component of flavins FAD and FMN, used as cofactors in redox reactions, eg, the succinate dehydrogenase reaction in the TCA cycleNiacin NAD linked Enzymes Lactate dehydrogenase Pyruvate dehydrogenase a-ketoglutarate dehydrogenase Isocitrate dehydrogenase Malate dehydrogenase Glutamate dehydrogenase Glyceraldehyde 3 phosphate dehydrogenase NADPH generating reaction Glucose 6 phosphate dehydrogenase in HMP shunt pathway 6 phospho Gluconate Dehydrogenase in HMP shunt pathway Malic enzyme NADP Malate Dehydrogenase 