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12  structures 67  species 0  interactions 263  sequences 7  architectures

Family: Cathelicidins (PF00666)

Summary: Cathelicidin

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This is the Wikipedia entry entitled "Cathelicidin". More...

Cathelicidin Edit Wikipedia article

Protein CAMP PDB 2FBS.png
Available structures
PDB Ortholog search: PDBe RCSB
Aliases CAMP, CAP-18, CAP18, CRAMP, FALL-39, FALL39, HSD26, LL37, cathelicidin antimicrobial peptide
External IDs OMIM: 600474 MGI: 108443 HomoloGene: 110678 GeneCards: CAMP
Gene location (Human)
Chromosome 3 (human)
Chr. Chromosome 3 (human)[1]
Chromosome 3 (human)
Genomic location for CAMP
Genomic location for CAMP
Band 3p21.31 Start 48,223,347 bp[1]
End 48,225,491 bp[1]
RNA expression pattern
PBB GE CAMP 210244 at fs.png
More reference expression data
Species Human Mouse
RefSeq (mRNA)



RefSeq (protein)



Location (UCSC) Chr 3: 48.22 – 48.23 Mb Chr 9: 109.85 – 109.85 Mb
PubMed search [3] [4]
View/Edit Human View/Edit Mouse

Cathelicidin-related antimicrobial peptides are a family of polypeptides primarily stored in the lysosomes of macrophages and polymorphonuclear leukocytes (PMNs).[5] Cathelicidins serve a critical role in mammalian innate immune defense against invasive bacterial infection.[6] The cathelicidin family of peptides are classified as antimicrobial peptides (AMPs). The AMP family also includes the defensins. Whilst the defensins share common structural features, cathelicidin-related peptides are highly heterogeneous.[6]

Members of the cathelicidin family of antimicrobial polypeptides are characterized by a highly conserved region (cathelin domain) and a highly variable cathelicidin peptide domain.[6]

Cathelicidin peptides have been isolated from many different species of mammals. Cathelicidins were originally found in neutrophils, but have since been found in many other cells including epithelial cells and macrophages after activation by bacteria, viruses, fungi, or the hormone 1,25-D, which is the hormonally active form of vitamin D.[7] The protein encoded by the human cathelicidin gene, CAMP, is cleaved into the LL-37 peptide, which has several immunological functions.


PDB 1kwi EBI.jpg
Crystal Structure Analysis of the Cathelicidin Motif of Protegrins
Symbol Cathelicidin
Pfam PF00666
Pfam clan CL0121
InterPro IPR001894
SCOP 1lyp
OPM superfamily 236
OPM protein 2k6o

Cathelicidins range in size from 12 to 80 amino acid residues and have a wide range of structures.[8] Most cathelicidins are linear peptides with 23-37 amino acid residues, and fold into amphipathic α-helices. Additionally cathelicidins may also be small-sized molecules (12-18 residues) with beta-hairpin structures, stabilized by one or two disulphide bonds. Even larger cathelicidin peptides (39-80 amino acid residues) are also present. These larger cathelicidins display repetitive proline motifs forming extended polyproline-type structures.[6]

The cathelicidin family shares primary sequence homology with the cystatin[9] family of cysteine proteinase inhibitors, although amino acid residues thought to be important in such protease inhibition are usually lacking.

Mechanism of antimicrobial activity

The general rule of the mechanism triggering cathelicidin action, like that of other antimicrobial peptides, involves the disintegration (damaging and puncturing) of cell membranes of organisms toward which the peptide is active.[10]

Mammalian orthologs

Cathelicidin peptides have been found in humans, monkeys, mice, rats, rabbits, guinea pigs, pandas, pigs, cattle, frogs, sheep, goats, chickens, and horses.

Currently identified cathelicidins include the following:[6]

  • Human: hCAP-18 (cleaved into LL-37 and FALL-39)
  • Rhesus monkey: RL-37
  • Mice:CRAMP-1/2, (Cathelicidin-related Antimicrobial Peptide[11]
  • Rats: rCRAMP
  • Rabbits: CAP-18
  • Guinea pig: CAP-11
  • Pigs: PR-39, Prophenin, PMAP-23,36,37
  • Cattle: BMAP-27,28,34 (Bovine Myeloid Antimicrobial Peptides); Bac5, Bac7
  • Frogs: cathelicidin-AL (found in Amolops loloensis)[12]
  • Sheep:
  • Goats:
  • Chickens: Four cathelicidins, fowlicidins 1,2,3 and cathelicidin Beta-1 [13]
  • Horses:
  • Pandas:
  • Tasmanian Devil: Saha-CATH5 [14]
  • Salmonids: CATH1 and CATH2

Clinical significance

NOTE: This article seems to be split between two pages. More about cathelicidin's clinical significance can be found on the page for its encoding gene, LL-37.

Patients with rosacea have elevated levels of cathelicidin and elevated levels of stratum corneum tryptic enzymes (SCTEs). Cathelicidin is cleaved into the antimicrobial peptide LL-37 by both kallikrein 5 and kallikrein 7 serine proteases. Excessive production of LL-37 is suspected to be a contributing cause in all subtypes of Rosacea.[15] Antibiotics have been used in the past to treat rosacea, but antibiotics may only work because they inhibit some SCTEs.[16]

Higher plasma levels of human cathelicidin antimicrobial protein (hCAP18), which are up-regulated by vitamin D, appear to significantly reduce the risk of death from infection in dialysis patients. Patients with a high level of this protein were 3.7 times more likely to survive kidney dialysis for a year without a fatal infection.[17]

Vitamin D up-regulates genetic expression of cathelicidin, which exhibits broad-spectrum microbicidal activity against bacteria, fungi, and viruses.[18][19] Cathelicidin rapidly destroys the lipoprotein membranes of microbes enveloped in phagosomes after fusion with lysosomes in macrophages.

See also


  1. ^ a b c GRCh38: Ensembl release 89: ENSG00000164047 - Ensembl, May 2017
  2. ^ a b c GRCm38: Ensembl release 89: ENSMUSG00000038357 - Ensembl, May 2017
  3. ^ "Human PubMed Reference:". 
  4. ^ "Mouse PubMed Reference:". 
  5. ^ "Entrez Gene: CAMP cathelicidin antimicrobial peptide". 
  6. ^ a b c d e Zanetti M (January 2004). "Cathelicidins, multifunctional peptides of the innate immunity". Journal of Leukocyte Biology. 75 (1): 39–48. doi:10.1189/jlb.0403147. PMID 12960280. 
  7. ^ Liu PT, Stenger S, Li H, Wenzel L, Tan BH, Krutzik SR, Ochoa MT, Schauber J, Wu K, Meinken C, Kamen DL, Wagner M, Bals R, Steinmeyer A, Zügel U, Gallo RL, Eisenberg D, Hewison M, Hollis BW, Adams JS, Bloom BR, Modlin RL (March 2006). "Toll-like receptor triggering of a vitamin D-mediated human antimicrobial response". Science. 311 (5768): 1770–3. doi:10.1126/science.1123933. PMID 16497887. 
  8. ^ Gennaro R, Zanetti M (2000). "Structural features and biological activities of the cathelicidin-derived antimicrobial peptides". Biopolymers. 55 (1): 31–49. doi:10.1002/1097-0282(2000)55:1<31::AID-BIP40>3.0.CO;2-9. PMID 10931440. 
  9. ^ Zaiou M, Nizet V, Gallo RL (May 2003). "Antimicrobial and protease inhibitory functions of the human cathelicidin (hCAP18/LL-37) prosequence". The Journal of Investigative Dermatology. 120 (5): 810–6. doi:10.1046/j.1523-1747.2003.12132.x. PMID 12713586. 
  10. ^ Kościuczuk EM, Lisowski P, Jarczak J, Strzałkowska N, Jóźwik A, Horbańczuk J, Krzyżewski J, Zwierzchowski L, Bagnicka E (December 2012). "Cathelicidins: family of antimicrobial peptides. A review". Molecular Biology Reports. 39 (12): 10957–70. doi:10.1007/s11033-012-1997-x. PMC 3487008Freely accessible. PMID 23065264. 
  11. ^ Gallo RL, Kim KJ, Bernfield M, Kozak CA, Zanetti M, Merluzzi L, Gennaro R (May 1997). "Identification of CRAMP, a cathelin-related antimicrobial peptide expressed in the embryonic and adult mouse". The Journal of Biological Chemistry. 272 (20): 13088–93. doi:10.1074/jbc.272.20.13088. PMID 9148921. 
  12. ^ Hao X, Yang H, Wei L, Yang S, Zhu W, Ma D, Yu H, Lai R (August 2012). "Amphibian cathelicidin fills the evolutionary gap of cathelicidin in vertebrate". Amino Acids. 43 (2): 677–85. doi:10.1007/s00726-011-1116-7. PMID 22009138. 
  13. ^ Achanta M, Sunkara LT, Dai G, Bommineni YR, Jiang W, Zhang G (May 2012). "Tissue expression and developmental regulation of chicken cathelicidin antimicrobial peptides". Journal of Animal Science and Biotechnology. 3 (1): 15. doi:10.1186/2049-1891-3-15. PMC 3436658Freely accessible. PMID 22958518. 
  14. ^ Peel E, Cheng Y, Djordjevic JT, Fox S, Sorrell TC, Belov K (October 2016). "Cathelicidins in the Tasmanian devil (Sarcophilus harrisii)". Scientific Reports. 6: 35019. doi:10.1038/srep35019. PMC 5057115Freely accessible. PMID 27725697. 
  15. ^ Reinholz M, Ruzicka T, Schauber J (May 2012). "Cathelicidin LL-37: an antimicrobial peptide with a role in inflammatory skin disease". Annals of Dermatology. 24 (2): 126–35. doi:10.5021/ad.2012.24.2.126. PMC 3346901Freely accessible. PMID 22577261. 
  16. ^ Yamasaki K, Di Nardo A, Bardan A, Murakami M, Ohtake T, Coda A, Dorschner RA, Bonnart C, Descargues P, Hovnanian A, Morhenn VB, Gallo RL (August 2007). "Increased serine protease activity and cathelicidin promotes skin inflammation in rosacea". Nature Medicine. 13 (8): 975–80. doi:10.1038/nm1616. PMID 17676051. 
  17. ^ Gombart AF, Bhan I, Borregaard N, Tamez H, Camargo CA, Koeffler HP, Thadhani R (February 2009). "Low plasma level of cathelicidin antimicrobial peptide (hCAP18) predicts increased infectious disease mortality in patients undergoing hemodialysis". Clinical Infectious Diseases. 48 (4): 418–24. doi:10.1086/596314. PMID 19133797. 
  18. ^ Zasloff M (January 2002). "Antimicrobial peptides of multicellular organisms". Nature. 415 (6870): 389–95. doi:10.1038/415389a. PMID 11807545. 
  19. ^ Kamen DL, Tangpricha V (May 2010). "Vitamin D and molecular actions on the immune system: modulation of innate and autoimmunity". Journal of Molecular Medicine. 88 (5): 441–50. doi:10.1007/s00109-010-0590-9. PMC 2861286Freely accessible. PMID 20119827. 

Further reading

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Cathelicidin Provide feedback

A novel protein family, showing a conserved proregion and a variable carboxyl-terminal antimicrobial domain. This region shows similarity to cystatins.

Literature references

  1. Zanetti M, Gennaro R, Romeo D; , FEBS Lett 1995;374:1-5.: Cathelicidins: a novel protein family with a common proregion and a variable C-terminal antimicrobial domain. PUBMED:7589491 EPMC:7589491

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External database links

This tab holds annotation information from the InterPro database.

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Domain organisation

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Pfam Clan

This family is a member of clan Cystatin (CL0121), which has the following description:

This superfamily includes cystatins and cathelicidins [1]. The cystatin superfamily comprises cysteine protease inhibitors that play key regulatory roles in protein degradation processes. The progenitor of this superfamily was most probably intracellular and lacked a signal peptide and disulfide bridges, much like the extant Giardia cystatin. A primordial gene duplication produced two ancestral eukaryotic lineages, cystatins and stefins. Stefins - included in Pfam:PF00031 - remain encoded by a single or a small number of genes throughout the eukaryotes, whereas the cystatins have undergone a more complex and dynamic evolution through numerous gene and domain duplications [2].

The clan contains the following 12 members:

Cathelicidins Cystatin DUF3889 FTP Latexin Monellin PP1 Spp-24 SQAPI Staphopain_pro YebF YPEB


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Seed source: Pfam-B_276 (release 2.1)
Previous IDs: none
Type: Domain
Sequence Ontology: SO:0000417
Author: Bateman A
Number in seed: 8
Number in full: 263
Average length of the domain: 95.80 aa
Average identity of full alignment: 34 %
Average coverage of the sequence by the domain: 58.25 %

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HMM build commands:
build method: hmmbuild -o /dev/null HMM SEED
search method: hmmsearch -Z 45638612 -E 1000 --cpu 4 HMM pfamseq
Model details:
Parameter Sequence Domain
Gathering cut-off 20.7 20.7
Trusted cut-off 20.7 20.7
Noise cut-off 20.6 20.6
Model length: 101
Family (HMM) version: 17
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Species distribution

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Archea Archea Eukaryota Eukaryota
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For those sequences which have a structure in the Protein DataBank, we use the mapping between UniProt, PDB and Pfam coordinate systems from the PDBe group, to allow us to map Pfam domains onto UniProt sequences and three-dimensional protein structures. The table below shows the structures on which the Cathelicidins domain has been found. There are 12 instances of this domain found in the PDB. Note that there may be multiple copies of the domain in a single PDB structure, since many structures contain multiple copies of the same protein sequence.

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