<prompt> Sulphur of cysteine are not usedutilised in the body for the following processproduct:Help in the conversion of cyanide to thiocyanateThiosulphate formationIntroduction of sulphur in methionineDisulphide bond formation between two adjacent peptide  <response>: Ans. C. Introduction of sulphur in methionine.Methionine is an essential amino acid, so it cannot be synthesized from Cysteine.But Sulphur of cysteine is donated by sulphur of methionine.This is called transulfuration reaction.PLP is the coenzyme of transulfuration.The reaction is catalysed by Cystathionine beta Synthase and Cystathionase enzyme. 