PROSITE documentation PDOC00242Mammalian defensins signature
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Defensins [1,2,3,4,5], also known as α-defensins, are a family of structurally related cysteine-rich peptides active against many Gram-negative and Gram-positive bacteria, fungi, and enveloped viruses. Some defensins are also called corticostatins (CS) because they inhibit corticotropin-stimulated corticosteroid production. Defensins kills cells by forming voltage-regulated multimeric channels in the susceptible cell's membrane. They play a significant role in innate immunity to infection and neoplasia. The peptides known to belong to this family are listed below.
- Rabbit defensins and corticostatins: CS-I (NP-3A), CS-II (NP-3B), CS-III (MCP-1), CS-IV (MCP-2), NP-4, and NP-5.
- Guinea-pig neutrophil defensin (GPNP).
- Human neutrophil defensins 1 to 4 and intestinal defensins 5 and 6.
- Mouse small bowel cryptdins 1 to 5.
- Rat NP-1 to NP-4.
All these peptides range in length from 29 to 35 amino acids. There are seven invariant residues, including six cysteines all involved in intrachain disulfide bonds. A schematic representation of peptides from the defensin family is shown below.
+----------------------------+
|****************************|
xxCxCxxxxxCxxxxxxxGxCxxxxxxxxxCCxx
| | | |
+-----|---------+ |
+-------------------+
'C': conserved cysteine involved in a disulfide bond. '*': position of the pattern.
Our pattern is based on the conserved residues.
Last update:May 2004 / Text revised.
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PROSITE method (with tools and information) covered by this documentation:
| 1 | Authors | Lehrer R.I. Ganz T. Selsted M.E. |
| Source | ASM News 56:315-318(1990). |
| 2 | Authors | Lehrer R.I. Ganz T. Selsted M.E. |
| Title | Defensins: endogenous antibiotic peptides of animal cells. | |
| Source | Cell 64:229-230(1991). | |
| PubMed ID | 1988144 |
| 3 | Authors | Kagan B.L. Ganz T. Lehrer R.I. |
| Title | Defensins: a family of antimicrobial and cytotoxic peptides. | |
| Source | Toxicology 87:131-149(1994). | |
| PubMed ID | 7512758 |
| 4 | Authors | Lehrer R.I. Lichtenstein A.K. Ganz T. |
| Title | Defensins: antimicrobial and cytotoxic peptides of mammalian cells. | |
| Source | Annu. Rev. Immunol. 11:105-128(1993). | |
| PubMed ID | 8476558 | |
| DOI | 10.1146/annurev.iy.11.040193.000541 |
| 5 | Authors | White S.H. Wimley W.C. Selsted M.E. |
| Title | Structure, function, and membrane integration of defensins. | |
| Source | Curr. Opin. Struct. Biol. 5:521-527(1995). | |
| PubMed ID | 8528769 |
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