| Structural highlights
Disease
HEPC_HUMAN Defects in HAMP are the cause of hemochromatosis type 2B (HFE2B) [MIM:613313; also known as juvenile hemochromatosis (JH). HFE2B is a disorder of iron metabolism with excess deposition of iron in the tissues, bronze skin pigmentation, hepatic cirrhosis, arthropathy and diabetes. The most common symptoms of hemochromatosis type 2 at presentation are hypogonadism and cardiomyopathy.[1] [2] [3] [4] [5]
Function
HEPC_HUMAN Seems to act as a signaling molecule involved in the maintenance of iron homeostasis. Seems to be required in conjunction with HFE to regulate both intestinal iron absorption and iron storage in macrophages (By similarity).[6] Has strong antimicrobial activity against E.coli ML35P N.cinerea and weaker against S.epidermidis, S.aureus and group b streptococcus bacteria. Active against the fungus C.albicans. No activity against P.aeruginosa.[7]
Publication Abstract from PubMed
The antibacterial and antifungal peptide hepcidin (LEAP-1) is expressed in the liver. This circulating peptide has recently been found to also act as a signaling molecule in iron metabolism. As such, it plays an important role in hereditary hemochromatosis, a serious iron overload disease. In this study, we report the solution structures of the hepcidin-20 and -25 amino acid peptides determined by standard two-dimensional (1)H NMR spectroscopy. These small cysteine-rich peptides form a distorted beta-sheet with an unusual vicinal disulfide bridge found at the turn of the hairpin, which is probably of functional significance. Both peptides exhibit an overall amphipathic structure with six of the eight Cys involved in maintaining interstrand connectivity. Hepcidin-25 assumes major and minor conformations centered about the Pro residue near the N-terminal end. Further NMR diffusion studies indicate that hepcidin-20 exists as a monomer in solution, whereas hepcidin-25 readily aggregates, a property that may contribute to the different activities of the two peptides. The nuclear Overhauser enhancement spectroscopy spectra of the hepcidin-25 aggregates indicate an interface for peptide interactions that again involves the first five residues from the N-terminal end.
The solution structure of human hepcidin, a peptide hormone with antimicrobial activity that is involved in iron uptake and hereditary hemochromatosis.,Hunter HN, Fulton DB, Ganz T, Vogel HJ J Biol Chem. 2002 Oct 4;277(40):37597-603. Epub 2002 Jul 22. PMID:12138110[8]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
References
- ↑ Biasiotto G, Belloli S, Ruggeri G, Zanella I, Gerardi G, Corrado M, Gobbi E, Albertini A, Arosio P. Identification of new mutations of the HFE, hepcidin, and transferrin receptor 2 genes by denaturing HPLC analysis of individuals with biochemical indications of iron overload. Clin Chem. 2003 Dec;49(12):1981-8. PMID:14633868 doi:10.1373/clinchem.2003.023440
- ↑ Merryweather-Clarke AT, Cadet E, Bomford A, Capron D, Viprakasit V, Miller A, McHugh PJ, Chapman RW, Pointon JJ, Wimhurst VL, Livesey KJ, Tanphaichitr V, Rochette J, Robson KJ. Digenic inheritance of mutations in HAMP and HFE results in different types of haemochromatosis. Hum Mol Genet. 2003 Sep 1;12(17):2241-7. Epub 2003 Jul 15. PMID:12915468 doi:http://dx.doi.org/10.1093/hmg/ddg225
- ↑ Roetto A, Daraio F, Porporato P, Caruso R, Cox TM, Cazzola M, Gasparini P, Piperno A, Camaschella C. Screening hepcidin for mutations in juvenile hemochromatosis: identification of a new mutation (C70R). Blood. 2004 Mar 15;103(6):2407-9. Epub 2003 Nov 20. PMID:14630809 doi:10.1182/blood-2003-10-3390
- ↑ Jacolot S, Le Gac G, Scotet V, Quere I, Mura C, Ferec C. HAMP as a modifier gene that increases the phenotypic expression of the HFE pC282Y homozygous genotype. Blood. 2004 Apr 1;103(7):2835-40. Epub 2003 Dec 11. PMID:14670915 doi:10.1182/blood-2003-10-3366
- ↑ Delatycki MB, Allen KJ, Gow P, MacFarlane J, Radomski C, Thompson J, Hayden MR, Goldberg YP, Samuels ME. A homozygous HAMP mutation in a multiply consanguineous family with pseudo-dominant juvenile hemochromatosis. Clin Genet. 2004 May;65(5):378-83. PMID:15099344 doi:10.1111/j.0009-9163.2004.00254.x
- ↑ Krause A, Neitz S, Magert HJ, Schulz A, Forssmann WG, Schulz-Knappe P, Adermann K. LEAP-1, a novel highly disulfide-bonded human peptide, exhibits antimicrobial activity. FEBS Lett. 2000 Sep 1;480(2-3):147-50. PMID:11034317
- ↑ Krause A, Neitz S, Magert HJ, Schulz A, Forssmann WG, Schulz-Knappe P, Adermann K. LEAP-1, a novel highly disulfide-bonded human peptide, exhibits antimicrobial activity. FEBS Lett. 2000 Sep 1;480(2-3):147-50. PMID:11034317
- ↑ Hunter HN, Fulton DB, Ganz T, Vogel HJ. The solution structure of human hepcidin, a peptide hormone with antimicrobial activity that is involved in iron uptake and hereditary hemochromatosis. J Biol Chem. 2002 Oct 4;277(40):37597-603. Epub 2002 Jul 22. PMID:12138110 doi:10.1074/jbc.M205305200
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