ENZYMATIC REACTIONS IN THE PRESENCE OF KETO ACIDS

摘要

Conversion in vitro of X-Gly to X-alpha-hydroxy-Gly or X-NH₂ (X being a peptide or any other compound having a carbonyl group capable of forming a covalent bond with glycine) is accomplished enzymatically in the presence of keto acids, or salts or esters thereof, to provide a good yield without the necessity of catalase or similar enzymatic reaction enhancers. Peptidylglycine a-amidating monooxygenase (PAM) is a preferred enzyme for catalyzing the conversion. Alternatively, peptidylglycine a-hydroxylating monooxygenase (PHM) is utilized to convert X-Gly to X-alpha-hdroxy-Gly which may be recovered, or optionally may be simultaneously or sequentially converted to an amid by either a Lewis base or action of the enzyme peptidyl a-hydroxyglycine A-amidating lyase (PAL). Both PHM and PAL are functional domains of PAM.