Enzyme deficient in maple syrup urine disease?
Maple syrup urine disease is due to deficiency of a-ketoacid dehydrogenase (also called a-ketoacid decarboxylase). In maple syrup urine disease there is excretion of branched chain amino acids (isoleucine, leucine, valine) and their keto acids (a-keto b-methylvalerate, a-ketoisocaproate, a-ketoisovalerate) in urine.
a-ketoacid decarboxylase
Transaminase
Isomerase
Mutase