<prompt> Methylcobalamin is required for which of the following enzymes:Homocysteine deaminaseHomocysteine methyl transferaseMethionine synthaseMethionine reductase  <response>: Ans. c Methionine synthaseRef.: Harpers Biochemistry 30th edn. 1558B CONVERSION OF HOMOCYSTEINE TO METHIONINE Active form in this reaction is methycobalamin. This reaction requires both methylcobalamin and folic acid. The reaction is catalyzed by methionine synthase which is a methylcobalamin dependent reaction.HomocysteineMethionine synthase---Methylcobalamin folic acidMethionine 