O-Acetylserine

O-Acetylserine is the α-amino acid with the chemical formula HO2CCH(NH2)CH2OC(O)CH3. It is an intermediate in the biosynthesis of the common amino acid cysteine in bacteria. O-Acetylserine is biosynthesized by acetylation of the serine by the enzyme serine transacetylase. The enzyme O-acetylserine (thiol)-lyase, using sulfide sources, converts this ester into cysteine, releaseing acetate:
 * HO2CCH(NH2)CH2OH →  HO2CCH(NH2)CH2OC(O)CH3
 * HO2CCH(NH2)CH2OC(O)CH3 →  HO2CCH(NH2)CH2SH