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5  structures 56  species 1  interaction 193  sequences 2  architectures

Family: Cathelicidins (PF00666)

Summary: Cathelicidin

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Cathelicidin Edit Wikipedia article

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
Cathelicidin antimicrobial peptide
Protein CAMP PDB 2FBS.png
Rendering based on PDB 2FBS.
Available structures
PDB Ortholog search: PDBe, RCSB
Symbols CAMP ; CAP-18; CAP18; CRAMP; FALL-39; FALL39; LL37
External IDs OMIM600474 MGI108443 HomoloGene110678 GeneCards: CAMP Gene
RNA expression pattern
PBB GE CAMP 210244 at tn.png
More reference expression data
Species Human Mouse
Entrez 820 12796
Ensembl ENSG00000164047 ENSMUSG00000038357
UniProt P49913 P51437
RefSeq (mRNA) NM_004345 NM_009921
RefSeq (protein) NP_004336 NP_034051
Location (UCSC) Chr 3:
48.26 – 48.27 Mb
Chr 9:
109.85 – 109.85 Mb
PubMed search [1] [2]

Cathelicidin-related antimicrobial peptides are a family of polypeptides found in lysosomes of macrophages and polymorphonuclear leukocytes (PMNs).[1] Cathelicidins serve a critical role in mammalian innate immune defense against invasive bacterial infection.[2]

Members of the cathelicidin family of antimicrobial polypeptides are characterized by a highly conserved region (cathelin domain) and a highly variable cathelicidin peptide domain.[2]

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.[3]

The cathelicidin family shares primary sequence homology with the cystatin[4] family of cysteine proteinase inhibitors, although amino acid residues thought to be important in such protease inhibition are usually lacking.


Cathelicidins range in size from 12 to 80 amino acid residues and have a wide range of structures.[5] Most cathelicidins are linear peptides with 23-37 amino acid residues, and fold into amphiphatic 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.[2]

Family members

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

Currently identified cathelicidins include the following:[2]

  • Human:hCAP-18/LL-37
  • Rhesus Monkey: RL-37
  • Mice:CRAMP-1/2, (Cathelicidin-related Antimicrobial Peptide[6]
  • 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)[7]
  • Sheep:
  • Goats:
  • Horses:
  • Pandas:

Clinical significance

Patients with rosacea have elevated levels of cathelicidin and elevated levels of stratum corneum tryptic enzymes (SCTEs). Antibiotics have been used in the past to treat rosacea, but antibiotics may only work because they inhibit some SCTEs.[8]

Higher 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.[9]

Vitamin D up-regulates genetic expression of cathelicidin, which exhibits broad-spectrum microbicidal activity against bacteria, fungi, and viruses.[10][11] Cathelicidin rapidly destroys the lipoprotein membranes of microbes enveloped in phagosomes after fusion with lysosomes in macrophages.

See also


  1. ^ "Entrez Gene: CAMP cathelicidin antimicrobial peptide". 
  2. ^ a b c d Zanetti M (January 2004). "Cathelicidins, multifunctional peptides of the innate immunity". J. Leukoc. Biol. 75 (1): 39–48. doi:10.1189/jlb.0403147. PMID 12960280. 
  3. ^ 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 R (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. 
  4. ^ Zaiou M, Nizet V, Gallo RL. (May 2003). "Antimicrobial and protease inhibitory functions of the human cathelicidin (hCAP18/LL-37) prosequence". J Invest Dermatol. 5 (120): 810–6. doi:10.1046/j.1523-1747.2003.12132.x3. PMID 12713586. 
  5. ^ 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. 
  6. ^ 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". J. Biol. Chem. 272 (20): 13088–93. doi:10.1074/jbc.272.20.13088. PMID 9148921. 
  7. ^ 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. 
  8. ^ 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". Nat. Med. 13 (8): 975–80. doi:10.1038/nm1616. PMID 17676051. 
  9. ^ 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". Clin. Infect. Dis. 48 (4): 418–24. doi:10.1086/596314. PMID 19133797. 
  10. ^ Zasloff M (January 2002). "Antimicrobial peptides of multicellular organisms". Nature 415 (6870): 389–95. doi:10.1038/415389a. PMID 11807545. 
  11. ^ Kamen DL, Tangpricha V (May 2010). "Vitamin D and molecular actions on the immune system: modulation of innate and autoimmunity". J. Mol. Med. 88 (5): 441–50. doi:10.1007/s00109-010-0590-9. PMC 2861286. 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

Internal database links

External database links

This tab holds annotation information from the InterPro database.

InterPro entry IPR001894

The precursor sequences of a number of antimicrobial peptides secreted by neutrophils (polymorphonuclear leukocytes) upon activation have been found to be evolutionarily related and are collectively known as cathelicidins [PUBMED:7589491].

Structurally, these proteins consist of three domains: a signal sequence, a conserved region of about 100 residues that contains four cysteines involved in two disulphide bonds, and a highly divergent C-terminal section of variable size. It is in this C-terminal section that the antibacterial peptides are found; they are proteolytically processed from their precursor by enzymes such as elastase. This structure is shown in the following schematic representation:

   |Sig| Propeptide     C  C  C  C      | Antibacterial pep. |
                        |  |  |  |
                        +--+  +--+
'C': conserved cysteine involved in a disulphide bond.

Gene Ontology

The mapping between Pfam and Gene Ontology is provided by InterPro. If you use this data please cite InterPro.

Domain organisation

Below is a listing of the unique domain organisations or architectures in which this domain is found. More...

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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 4 members:

Cathelicidins Cystatin PP1 Spp-24


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Curation and family details

This section shows the detailed information about the Pfam family. You can see the definitions of many of the terms in this section in the glossary and a fuller explanation of the scoring system that we use in the scores section of the help pages.

Curation View help on the curation process

Seed source: Pfam-B_276 (release 2.1)
Previous IDs: none
Type: Family
Author: Bateman A
Number in seed: 8
Number in full: 193
Average length of the domain: 65.00 aa
Average identity of full alignment: 50 %
Average coverage of the sequence by the domain: 41.10 %

HMM information View help on HMM parameters

HMM build commands:
build method: hmmbuild -o /dev/null HMM SEED
search method: hmmsearch -Z 23193494 -E 1000 --cpu 4 HMM pfamseq
Model details:
Parameter Sequence Domain
Gathering cut-off 20.7 20.7
Trusted cut-off 20.8 20.7
Noise cut-off 20.6 20.4
Model length: 67
Family (HMM) version: 12
Download: download the raw HMM for this family

Species distribution

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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 5 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 seqence.

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