Identification in pituitary tissue of a peptide alpha-amidation activity that acts on glycine-extended peptides and requires molecular oxygen, copper, and ascorbic acid - PubMed (original) (raw)

Comparative Study

Identification in pituitary tissue of a peptide alpha-amidation activity that acts on glycine-extended peptides and requires molecular oxygen, copper, and ascorbic acid

B A Eipper et al. Proc Natl Acad Sci U S A. 1983 Aug.

Abstract

An enzymatic activity capable of producing an alpha-amidated peptide product from its glycine-extended precursor has been identified in secretory granules of rat anterior, intermediate, and neural pituitary and bovine intermediate pituitary. High levels of endogenous inhibitors of this alpha-amidation activity have also been found in tissue homogenates. The alpha-amidation activity is totally inhibited by addition of divalent metal ion chelators such as diethyldithiocarbamate, o-phenanthroline, and EDTA; alpha-amidation activity is restored to above control levels upon addition of copper. The alpha-amidation reaction requires the presence of molecular oxygen. Of the various cofactors tested, ascorbic acid was the most potent stimulator of alpha-amidation. The alpha-amidation activity has a neutral pH optimum and is primarily soluble following several cycles of freezing and thawing. Kinetic studies with the bovine intermediate pituitary granule-associated activity demonstrated a linear Lineweaver-Burk plot when D-Tyr-Val-Gly was the varied substrate; the apparent Km and Vmax varied with the concentration of ascorbic acid. The substrate specificity of the alpha-amidation activity appears to be quite broad; the conversion of D-Tyr-Val-Gly into D-Tyr-Val-NH2 is inhibited by the addition of a variety of glycine-extended peptides.

PubMed Disclaimer

Cited by

The crystal structure of human dopamine β-hydroxylase at 2.9 Å resolution.
Vendelboe TV, Harris P, Zhao Y, Walter TS, Harlos K, El Omari K, Christensen HE. Vendelboe TV, et al. Sci Adv. 2016 Apr 8;2(4):e1500980. doi: 10.1126/sciadv.1500980. eCollection 2016 Apr. Sci Adv. 2016. PMID: 27152332 Free PMC article.
Molecular cloning, cDNA sequencing, and chemical synthesis of cecropin B from Hyalophora cecropia.
van Hofsten P, Faye I, Kockum K, Lee JY, Xanthopoulos KG, Boman IA, Boman HG, Engström A, Andreu D, Merrifield RB. van Hofsten P, et al. Proc Natl Acad Sci U S A. 1985 Apr;82(8):2240-3. doi: 10.1073/pnas.82.8.2240. Proc Natl Acad Sci U S A. 1985. PMID: 3857578 Free PMC article.
Identification of a mammalian glutaminyl cyclase converting glutaminyl into pyroglutamyl peptides.
Fischer WH, Spiess J. Fischer WH, et al. Proc Natl Acad Sci U S A. 1987 Jun;84(11):3628-32. doi: 10.1073/pnas.84.11.3628. Proc Natl Acad Sci U S A. 1987. PMID: 3473473 Free PMC article.
Plasma peptidylglycine alpha-amidating monooxygenase (PAM) and ceruloplasmin are affected by age and copper status in rats and mice.
Prohaska JR, Broderius M. Prohaska JR, et al. Comp Biochem Physiol B Biochem Mol Biol. 2006 Mar;143(3):360-6. doi: 10.1016/j.cbpb.2005.12.010. Epub 2006 Jan 31. Comp Biochem Physiol B Biochem Mol Biol. 2006. PMID: 16448835 Free PMC article.
Processing and secretion in the neurohypophysis. Stability of isolated secretory vesicles and role of internal pH.
Saermark T, Andersen NM, Atke A, Jones PM, Vilhardt H. Saermark T, et al. Biochem J. 1986 May 15;236(1):77-84. doi: 10.1042/bj2360077. Biochem J. 1986. PMID: 2947570 Free PMC article.

References

1. Biochem Pharmacol. 1976 May 15;25(10):1167-74 - PubMed
1. Biochim Biophys Acta. 1980 Mar 3;628(2):182-9 - PubMed
1. J Biol Chem. 1981 Mar 10;256(5):2258-61 - PubMed
1. Ciba Found Symp. 1980;79:163-82 - PubMed
1. Brain Res Bull. 1981 Sep;7(3):237-42 - PubMed

Identification in pituitary tissue of a peptide alpha-amidation activity that acts on glycine-extended peptides and requires molecular oxygen, copper, and ascorbic acid - PubMed (original) (raw)