Reaction: [peptide]-glycine + 2 ascorbate + O2 = [peptide]-(2S)-2-hydroxyglycine + 2 monodehydroascorbate + H2O
Other name(s): peptidylglycine 2-hydroxylase; peptidyl α-amidating enzyme; peptide-α-amide synthetase; peptide α-amidating enzyme; peptide α-amide synthase; peptidylglycine α-hydroxylase; peptidylglycine α-amidating monooxygenase; PAM-A; PAM-B; PAM; peptidylglycine,ascorbate:oxygen oxidoreductase (2-hydroxylating)
Systematic name: [peptide]-glycine,ascorbate:oxygen oxidoreductase (2-hydroxylating)
Comments: A copper protein. The enzyme binds two copper ions with distinct roles during catalysis. Peptidylglycines with a neutral amino acid residue in the penultimate position are the best substrates for the enzyme. The product is unstable and dismutates to glyoxylate and the corresponding desglycine peptide amide, a reaction catalysed by EC 4.3.2.5 peptidylamidoglycolate lyase. In mammals, the two activities are part of a bifunctional protein. Involved in the final step of biosynthesis of α-melanotropin and related biologically active peptides.
Links to other databases: BRENDA, EXPASY, KEGG, MetaCyc, PDB, CAS registry number: 90597-47-0
References:
1. Bradbury, A.F., Finnie, M.D.A. and Smyth, D.G. Mechanism of C-terminal amide formation by pituitary enzymes. Nature (Lond.) 298 (1982) 686-688. [PMID: 7099265]
2. Glembotski, C.G. Further characterization of the peptidyl α-amidating enzyme in rat anterior pituitary secretory granules. Arch. Biochem. Biophys. 241 (1985) 673-683. [PMID: 2994573]
3. Murthy, A.S.N., Mains, R.E. and Eipper, B.A. Purification and characterization of peptidylglycine α-amidating monooxygenase from bovine neurointermediate pituitary. J. Biol. Chem. 261 (1986) 1815-1822. [PMID: 3944110]
4. Bradbury, A.F. and Smyth, D.G. Enzyme-catalysed peptide amidation. Isolation of a stable intermediate formed by reaction of the amidating enzyme with an imino acid. Eur. J. Biochem. 169 (1987) 579-584. [PMID: 3691506]
5. Murthy, A.S.N., Keutmann, H.T. and Eipper, B.A. Further characterization of peptidylglycine α-amidating monooxygenase from bovine neurointermediate pituitary. Mol. Endocrinol. 1 (1987) 290-299. [PMID: 3453894]
6. Katopodis, A.G., Ping, D. and May, S.W. A novel enzyme from bovine neurointermediate pituitary catalyzes dealkylation of α-hydroxyglycine derivatives, thereby functioning sequentially with peptidylglycine α-amidating monooxygenase in peptide amidation. Biochemistry 29 (1990) 6115-6120. [PMID: 2207061]
7. Prigge, S.T., Kolhekar, A.S., Eipper, B.A., Mains, R.E. and Amzel, L.M. Amidation of bioactive peptides: the structure of peptidylglycine α-hydroxylating monooxygenase. Science 278 (1997) 1300-1305. [PMID: 9360928]
8. Prigge, S.T., Eipper, B.A., Mains, R.E. and Amzel, L.M. Dioxygen binds end-on to mononuclear copper in a precatalytic enzyme complex. Science 304 (2004) 864-867. [PMID: 15131304]
9. Chufan, E.E., Prigge, S.T., Siebert, X., Eipper, B.A., Mains, R.E. and Amzel, L.M. Differential reactivity between two copper sites in peptidylglycine α-hydroxylating monooxygenase. J. Am. Chem. Soc. 132 (2010) 15565-15572. [PMID: 20958070]
10. Chauhan, S., Hosseinzadeh, P., Lu, Y. and Blackburn, N.J. Stopped-flow studies of the reduction of the copper centers suggest a bifurcated electron transfer pathway in peptidylglycine monooxygenase. Biochemistry 55 (2016) 2008-2021. [PMID: 26982589]