The co-evolution of host cationic antimicrobial peptides and microbial resistance

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Endogenous cationic antimicrobial peptides (CAMPs) are among the most ancient and efficient components of host defence. It is somewhat of an enigma that bacteria have not developed highly effective CAMP-resistance mechanisms, such as those that inhibit many therapeutic antibiotics. Here, we propose that CAMPs and CAMP-resistance mechanisms have co-evolved, leading to a transient host–pathogen balance that has shaped the existing CAMP repertoire. Elucidating the underlying principles of this process could help in the development of more sustainable antibiotics.

Key Points

  • Host–pathogen interactions are a result of long-term co-evolution and adaptation processes. Endogenous cationic antimicrobial peptides (CAMPs) such as defensins, cathelicidins and kinocidins are produced by virtually all classes of organisms and belong to the oldest and most effective components of antimicrobial host defence. Host CAMPs and bacterial CAMP-resistance mechanisms represent an intriguing example of host–pathogen co-evolution.

  • CAMP genes are subject to positive selection and CAMPs belong to the most rapidly evolving group of mammalian proteins, with major differences even between primate species. Some CAMPs are conserved throughout the various mammalian lineages, whereas others seem to have appeared, disappeared or expanded by gene multiplication in a subset of mammalian families.

  • Several bacterial pathogens can resist certain CAMPs to some extent by, for example, proteolytic cleavage, CAMP-specific binding or extrusion mechanisms, or by modifications to the bacterial surface that reduce the affinity for CAMPs. However, it is still unclear how the emergence and adaptation of microbial CAMP-resistance mechanisms has affected the evolution of CAMPs.

  • It is proposed that the emergence of bacterial CAMP resistance has had a profound effect on the evolution of CAMP variants. The introduction of stabilizing disulphide bridges into CAMPs, extensive variation of peptide sequences and adaptation of the electrostatic properties of CAMPs might contribute to the ongoing development of host strategies to circumvent microbial CAMP resistance, leading to continuously effective antimicrobial peptides.

  • Drawing the correct conclusions from the ongoing effectiveness of CAMPs might help to avoid the rapid loss of efficacy of therapeutic antibiotics and to design new, 'smarter' antibiotics. In addition to the proposed host-adaptation strategies, conceptual differences between the mode of action of CAMPs and antibiotics might have played key roles in the extraordinary success of CAMPs during evolution.

  • The combination of two or more antimicrobial mechanisms in one molecule, the targeting of essential, non-protein bacterial structures such as the cytoplasmic membrane, and the availability of CAMPs in high concentrations at sites of infection, could have been major obstacles for bacteria to develop highly effective CAMP resistance. Incorporating such properties into novel therapeutic antibiotics represents a major challenge for future antimicrobial drug design.

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Figure 1: Diversity of human cationic antimicrobial peptides.
Figure 2: Bacterial cationic antimicrobial peptide (CAMP)-resistance mechanisms.
Figure 3: Co-evolution of cationic antimicrobial peptides (CAMPs) and bacterial CAMP-resistance mechanisms.
Figure 4: Nisin and its various modes of antimicrobial action.


  1. 1

    Woolhouse, M. E., Webster, J. P., Domingo, E., Charlesworth, B. & Levin, B. R. Biological and biomedical implications of the co-evolution of pathogens and their hosts. Nature Genet. 32, 569–577 (2002).

  2. 2

    Grenfell, B. T. et al. Unifying the epidemiological and evolutionary dynamics of pathogens. Science 303, 327–332 (2004).

  3. 3

    Brubaker, R. R. The recent emergence of plague: a process of felonious evolution. Microb. Ecol. 47, 293–299 (2004).

  4. 4

    Waldvogel, F. A. Infectious diseases in the 21st century: old challenges and new opportunities. Int. J. Infect. Dis. 8, 5–12 (2004).

  5. 5

    Zasloff, M. Antimicrobial peptides of multicellular organisms. Nature 415, 389–395 (2002). This is a comprehensive review on the diversity, structure, activity and possible applications of endogenous antimicrobial peptides from higher organisms.

  6. 6

    Hancock, R. E. W. & Diamond, G. The role of cationic antimicrobial peptides in innate host defences. Trends Microbiol. 8, 402–410 (2000).

  7. 7

    Ganz, T. Defensins: antimicrobial peptides of innate immunity. Nature Rev. Immunol. 3, 710–720 (2003).

  8. 8

    Lehrer, R. I. Primate defensins. Nature Rev. Microbiol. 2, 727–738 (2004).

  9. 9

    Brogden, K. A. Antimicrobial peptides: pore formers or metabolic inhibitors in bacteria? Nature Rev. Microbiol. 3, 238–250 (2005).

  10. 10

    Selsted, M. E. & Ouellette, A. J. Mammalian defensins in the antimicrobial immune response. Nature Immunol. 6, 551–557 (2005).

  11. 11

    Dorschner, R. A. et al. The mammalian ionic environment dictates microbial susceptibility to antimicrobial defense peptides. FASEB J. 20, 35–42 (2006).

  12. 12

    Sahl, H. G. et al. Mammalian defensins: structures and mechanism of antibiotic activity. J. Leukoc. Biol. 77, 466–475 (2005). This article compares the antibacterial and membrane-disrupting properties of mammalian defensins.

  13. 13

    Yang, D., Biragyn, A., Kwak, L. W. & Oppenheim, J. J. Mammalian defensins in immunity: more than just microbicidal. Trends Immunol. 23, 291–296 (2002).

  14. 14

    Bals, R. & Wilson, J. M. Cathelicidins — a family of multifunctional antimicrobial peptides. Cell. Mol. Life Sci. 60, 711–720 (2003).

  15. 15

    Bowdish, D. M. et al. Impact of LL-37 on anti-infective immunity. J. Leukoc. Biol. 77, 451–459 (2005).

  16. 16

    Dürr, M. & Peschel, A. Chemokines meet defensins — the merging concepts of chemoattractants and antimicrobial peptides in host defense. Infect. Immun. 70, 6515–6517 (2002).

  17. 17

    Rosenfeld, Y., Papo, N. & Shai, Y. Endotoxin (LPS) neutralization by innate immunity host-defense peptides: peptides' properties and plausible modes of action. J. Biol. Chem. 281, 1636–1643 (2006).

  18. 18

    Vallender, E. J. & Lahn, B. T. Positive selection on the human genome. Hum. Mol. Genet. 13,R245–R254 (2004).

  19. 19

    Patil, A., Hughes, A. L. & Zhang, G. Rapid evolution and diversification of mammalian α-defensins as revealed by comparative analysis of rodent and primate genes. Physiol. Genomics 20, 1–11 (2004).

  20. 20

    Nusbaum, C. et al. DNA sequence and analysis of human chromosome 8. Nature 439, 331–335 (2006).

  21. 21

    Crovella, S. et al. Primate β-defensins — structure, function and evolution. Curr. Protein Pept. Sci. 6, 7–21 (2005). This article describes the diversity of defensin structures in primate species.

  22. 22

    Nizet, V. in Antimicrobial Peptides in Human Health and Disease (ed. Gallo, R. L.) 277–304 (Horizon Bioscience, Norfolk, 2005).

  23. 23

    Peschel, A. How do bacteria resist human antimicrobial peptides? Trends Microbiol. 10, 179–186 (2002).

  24. 24

    Kraus, D. & Peschel, A. Molecular mechanisms of bacterial resistance to antimicrobial peptides. Curr. Top. Microbiol. Immunol. 306, 231–250 (2006).

  25. 25

    Kristian, S. A. et al. Alanylation of teichoic acids protects Staphylococcus aureus against Toll-like receptor 2-dependent host defense in a mouse tissue cage infection model. J. Infect. Dis. 188, 414–423 (2003).

  26. 26

    Nizet, V. et al. Innate antimicrobial peptide protects the skin from invasive bacterial infection. Nature 414, 454–457 (2001). This article demonstrates the important role of CAMPs in host defence using transgenic mice lacking the murine homologue of LL-37.

  27. 27

    Gunn, J. S., Ryan, S. S., Van Velkinburgh, J. C., Ernst, R. K. & Miller, S. I. Genetic and functional analysis of a PmrA–PmrB-regulated locus necessary for lipopolysaccharide modification, antimicrobial peptide resistance, and oral virulence of Salmonella enterica serovar Typhimurium. Infect. Immun. 68, 6139–6146 (2000).

  28. 28

    Weidenmaier, C. et al. DltABCD- and MprF-mediated cell envelope modifications of Staphylococcus aureus confer resistance to platelet microbicidal proteins and contribute to virulence in a rabbit endocarditis model. Infect. Immun. 73, 8033–8038 (2005).

  29. 29

    Kramer, N. E., van Hijum, S. A. F. T., Knol, J., Kok, J. & Kuipers, O. Transcriptome analysis reveals mechanisms by which Lactococcus lactis acquires nisin resistance. Antimicrob. Agents Chemother. 50, 1753–1761 (2006).

  30. 30

    Perron, G. G., Zasloff, M. & Bell, G. Experimental evolution of resistance to an antimicrobial peptide. Proc. Biol. Sci. 273, 251–256 (2006). This article demonstrates that bacteria can become spontaneously resistant to endogenous antimicrobial peptides on in vitro exposure to slowly increasing peptide concentrations.

  31. 31

    Levy, S. B. & Marshall, B. Antibacterial resistance worldwide: causes, challenges and responses. Nature Med. 10, S122–S129 (2004).

  32. 32

    Chambers, H. F. Community-associated MRSA — resistance and virulence converge. N. Engl. J. Med. 352, 1485–1487 (2005).

  33. 33

    Foster, T. J. The Staphylococcus aureus 'superbug'. J. Clin. Invest. 114, 1693–1696 (2004).

  34. 34

    Andres, E. & Dimarcq, J. L. Cationic antimicrobial peptides: update of clinical development. J. Intern. Med. 255, 519–520 (2004).

  35. 35

    Mygind, P. H. et al. Plectasin is a peptide antibiotic with therapeutic potential from a saprophytic fungus. Nature 437, 975–980 (2005).

  36. 36

    Sieprawska-Lupa, M. et al. Degradation of human antimicrobial peptide LL-37 by Staphylococcus aureus-derived proteinases. Antimicrob. Agents Chemother. 48, 4673–4679 (2004).

  37. 37

    Guina, T., Yi, E. C., Wang, H., Hackett, M. & Miller, S. I. A PhoP-regulated outer membrane protease of Salmonella enterica serovar Typhimurium promotes resistance to α-helical antimicrobial peptides. J. Bacteriol. 182, 4077–4086 (2000).

  38. 38

    Nyberg, P., Rasmussen, M. & Bjorck, L. α2-Macroglobulin-proteinase complexes protect Streptococcus pyogenes from killing by the antimicrobial peptide LL-37. J. Biol. Chem. 279, 52820–52823 (2004).

  39. 39

    Schmidtchen, A., Frick, I. M., Andersson, E., Tapper, H. & Bjorck, L. Proteinases of common pathogenic bacteria degrade and inactivate the antibacterial peptide LL-37. Mol. Microbiol. 46, 157–168 (2002).

  40. 40

    Wu, Z. et al. Engineering disulfide bridges to dissect antimicrobial and chemotactic activities of human β-defensin 3. Proc. Natl Acad. Sci. USA 100, 8880–8885 (2003). This article analyses different structural requirements for antimicrobial or chemotactic activity of CAMPs.

  41. 41

    Maemoto, A. et al. Functional analysis of the α-defensin disulfide array in mouse cryptdin-4. J. Biol. Chem. 279, 44188–44196 (2004).

  42. 42

    Campopiano, D. J. et al. Structure–activity relationships in defensin dimers: a novel link between β-defensin tertiary structure and antimicrobial activity. J. Biol. Chem. 279, 48671–48679 (2004).

  43. 43

    Rozek, A., Powers, J. P., Friedrich, C. L. & Hancock, R. E. Structure-based design of an indolicidin peptide analogue with increased protease stability. Biochemistry 42, 14130–14138 (2003).

  44. 44

    Harwig, S. S. et al. Intramolecular disulfide bonds enhance the antimicrobial and lytic activities of protegrins at physiological sodium chloride concentrations. Eur. J. Biochem. 240, 352–357 (1996).

  45. 45

    Hornef, M. W., Putsep, K., Karlsson, J., Refai, E. & Andersson, M. Increased diversity of intestinal antimicrobial peptides by covalent dimer formation. Nature Immunol. 5, 836–843 (2004). This article describes how the formation of heterodimers by murine CRS peptides leads to multiple antimicrobial molecules with different activity spectra.

  46. 46

    Tang, Y. Q. et al. A cyclic antimicrobial peptide produced in primate leukocytes by the ligation of two truncated α-defensins. Science 286, 498–502 (1999).

  47. 47

    Jack, R. W., Bierbaum, G. & Sahl, H.-G. Lantibiotics and Related Peptides (Springer, Berlin, 1998).

  48. 48

    Cotter, P. D., Hill, C. & Ross, R. P. Bacteriocins: developing innate immunity for food. Nature Rev. Microbiol. 3, 777–788 (2005).

  49. 49

    Tjabringa, G. S. et al. Host defense effector molecules in mucosal secretions. FEMS Immunol. Med. Microbiol. 45, 151–158 (2005).

  50. 50

    Jin, T. et al. Staphylococcus aureus resists human defensins by production of staphylokinase, a novel bacterial evasion mechanism. J. Immunol. 172, 1169–1176 (2004).

  51. 51

    Frick, I. M., Akesson, P., Rasmussen, M., Schmidtchen, A. & Bjorck, L. SIC, a secreted protein of Streptococcus pyogenes that inactivates antibacterial peptides. J. Biol. Chem. 278, 16561–16566 (2003).

  52. 52

    Shafer, W. M., Qu, X.-D., Waring, A. J. & Lehrer, R. I. Modulation of Neisseria gonorrhoeae susceptibility to vertebrate antibacterial peptides due to a member of the resistance/nodulation/division efflux pump family. Proc. Natl Acad. Sci. USA 95, 1829–1833 (1998). This article describes the first multiple drug resistance protein involved in CAMP resistance.

  53. 53

    Tzeng, Y. L. et al. Cationic antimicrobial peptide resistance in Neisseria meningitidis. J. Bacteriol. 187, 5387–5396 (2005).

  54. 54

    Fernie-King, B. A., Seilly, D. J. & Lachmann, P. J. The interaction of streptococcal inhibitor of complement (SIC) and its proteolytic fragments with the human β-defensins. Immunology 111, 444–452 (2004).

  55. 55

    Douglas, S. E., Gallant, J. W., Liebscher, R. S., Dacanay, A. & Tsoi, S. C. Identification and expression analysis of hepcidin-like antimicrobial peptides in bony fish. Dev. Comp. Immunol. 27, 589–601 (2003).

  56. 56

    Park, C. H., Valore, E. V., Waring, A. J. & Ganz, T. Hepcidin, a urinary antimicrobial peptide synthesized in the liver. J. Biol. Chem. 276, 7806–7810 (2001).

  57. 57

    Ouellette, A. J. & Selsted, M. E. Paneth cell defensins: endogenous peptide components of intestinal host defense. FASEB J. 10, 1280–1289 (1996).

  58. 58

    Eckmann, L. Defence molecules in intestinal innate immunity against bacterial infections. Curr. Opin. Gastroenterol. 21, 147–151 (2005).

  59. 59

    Taudien, S. et al. Polymorphic segmental duplications at 8p23.1 challenge the determination of individual defensin gene repertoires and the assembly of a contiguous human reference sequence. BMC Genomics 5, 92 (2004).

  60. 60

    Ernst, R. K., Guina, T. & Miller, S. I. Salmonella typhimurium outer membrane remodeling: role in resistance to host innate immunity. Microbes Infect. 3, 1327–1334 (2001).

  61. 61

    Neuhaus, F. C. & Baddiley, J. A continuum of anionic charge: structures and functions of D-alanyl-teichoic acids in Gram-positive bacteria. Microbiol. Mol. Biol. Rev. 67, 686–723 (2003).

  62. 62

    Peschel, A. et al. Inactivation of the dlt operon in Staphylococcus aureus confers sensitivity to defensins, protegrins and other antimicrobial peptides. J. Biol. Chem. 274, 8405–8410 (1999). This article describes CAMP resistance by alterations of the Gram-positive cell envelope, paralleling lipid A modifications in Gram-negative bacteria.

  63. 63

    Abachin, E. et al. Formation of D-alanyl-lipoteichoic acid is required for adhesion and virulence of Listeria monocytogenes. Mol. Microbiol. 43, 1–14 (2002).

  64. 64

    Poyart, C. et al. Attenuated virulence of Streptococcus agalactiae deficient in D-alanyl-lipoteichoic acid is due to an increased susceptibility to defensins and phagocytic cells. Mol. Microbiol. 49, 1615–1625 (2003).

  65. 65

    Kristian, S. A. et al. D-alanylation of teichoic acid promotes group A Streptococcus antimicrobial peptide resistance, neutrophil survival, and epithelial cell invasion. J. Bacteriol. 187, 6719–6725 (2005).

  66. 66

    Peschel, A. et al. Staphylococcus aureus resistance to human defensins and evasion of neutrophil killing via the novel virulence factor MprF is based on modification of membrane lipids with L-lysine. J. Exp. Med. 193, 1067–1076 (2001).

  67. 67

    Weidenmaier, C., Kristian, S. A. & Peschel, A. Bacterial resistance to antimicrobial host defenses — an emerging target for novel antiinfective strategies? Curr. Drug Targets 4, 643–649 (2003).

  68. 68

    Miller, S. I., Ernst, R. K. & Bader, M. W. LPS, TLR4 and infectious disease diversity. Nature Rev. Microbiol. 3, 36–46 (2005).

  69. 69

    Koprivnjak, T., Peschel, A., Gelb, M. H., Liang, N. S. & Weiss, J. P. Role of charge properties of bacterial envelope in bactericidal action of human Group IIA phospholipase A2 against Staphylococcus aureus. J. Biol. Chem. 277, 47636–47644 (2002).

  70. 70

    Collins, L. V. et al. Staphylococcus aureus strains lacking D-alanine modifications of teichoic acids are highly susceptible to human neutrophil killing and are virulence attenuated in mice. J. Infect. Dis. 186, 214–219 (2002).

  71. 71

    Midorikawa, K. et al. Staphylococcus aureus susceptibility to innate antimicrobial peptides, β-defensins and CAP18, expressed by human keratinocytes. Infect. Immun. 71, 3730–3739 (2003).

  72. 72

    Weidenmaier, C. et al. Role of teichoic acids in Staphylococcus aureus nasal colonization, a major risk factor in nosocomial infections. Nature Med. 10, 243–245 (2004).

  73. 73

    Harder, J., Bartels, J., Christophers, E. & Schroder, J. M. Isolation and characterization of human β-defensin-3, a novel human inducible peptide antibiotic. J. Biol. Chem. 276, 5707–5713 (2001).

  74. 74

    Shafer, W. M., Casey, S. G. & Spitznagel, J. K. Lipid A and resistance of Salmonella typhimurium to antimicrobial granule proteins of human neutrophil granulocytes. Infect. Immun. 43, 834–838 (1984).

  75. 75

    Guo, L. et al. Lipid A acylation and bacterial resistance against vertebrate antimicrobial peptides. Cell 95, 189–198 (1998).

  76. 76

    Vuong, C. et al. Polysaccharide intercellular adhesin (PIA) protects Staphylococcus epidermidis against major components of the human innate immune system. Cell. Microbiol. 6, 269–275 (2004).

  77. 77

    Otto, M. Bacterial evasion of antimicrobial peptides by biofilm formation. Curr. Top. Microbiol. Immunol. 306, 251–258 (2006).

  78. 78

    Ginsburg, I. The role of bacteriolysis in the pathophysiology of inflammation, infection and post-infectious sequelae. APMIS 110, 753–770 (2002).

  79. 79

    Breukink, E. et al. Use of the cell wall precursor lipid II by a pore-forming peptide antibiotic. Science 286, 2361–2364 (1999).

  80. 80

    Wiedemann, I. et al. Specific binding of nisin to the peptidoglycan precursor lipid II combines pore formation and inhibition of cell wall biosynthesis for potent antibiotic activity. J. Biol. Chem. 276, 1772–1779 (2001). This article demonstrates the combination of several antimicrobial mechanisms in the antimicrobial peptide nisin.

  81. 81

    Bierbaum, G. & Sahl, H. G. Induction of autolysis of staphylococci by the basic peptide antibiotic pep5 and nisin and their influence on the activity of autolytic enzymes. Arch. Microbiol. 141, 249–254 (1985).

  82. 82

    Pag, U. & Sahl, H. G. Multiple activities in lantibiotics — models for the design of novel antibiotics? Curr. Pharm. Des. 8, 815–833 (2002).

  83. 83

    Gravesen, A., Jydegaard Axelsen, A. M., Mendes, d. S., Hansen, T. B. & Knochel, S. Frequency of bacteriocin resistance development and associated fitness costs in Listeria monocytogenes. Appl. Environ. Microbiol. 68, 756–764 (2002).

  84. 84

    Ganz, T. Hepcidin in iron metabolism. Curr. Opin. Hematol. 11, 251–254 (2004).

  85. 85

    Nguyen, T. X., Cole, A. M. & Lehrer, R. I. Evolution of primate θ-defensins: a serpentine path to a sweet tooth. Peptides 24, 1647–1654 (2003).

  86. 86

    Fowler, V. G. Jr et al. Persistent bacteremia due to methicillin-resistant Staphylococcus aureus infection is associated with agr dysfunction and low-level in vitro resistance to thrombin-induced platelet microbicidal protein. J. Infect. Dis. 190, 1140–1149 (2004).

  87. 87

    Fowler, V. G. Jr et al. In vitro resistance to thrombin-induced platelet microbicidal protein in isolates of Staphylococcus aureus from endocarditis patients correlates with an intravascular device source. J. Infect. Dis. 182, 1251–1254 (2000).

  88. 88

    Frantz, S. Drug discovery: playing dirty. Nature 437, 942–943 (2005).

  89. 89

    Arthur, M., Reynolds, P. & Courvalin, P. Glycopeptide resistance in enterococci. Trends Microbiol. 4, 401–407 (1996).

  90. 90

    Allen, N. E. & Nicas, T. I. Mechanism of action of oritavancin and related glycopeptide antibiotics. FEMS Microbiol. Rev. 26, 511–532 (2003).

  91. 91

    Zhang, H. Z., Hackbarth, C. J., Chansky, K. M. & Chambers, H. F. A proteolytic transmembrane signaling pathway and resistance to β-lactams in staphylococci. Science 291, 1962–1965 (2001).

  92. 92

    Bader, M. W. et al. Recognition of antimicrobial peptides by a bacterial sensor kinase. Cell 122, 461–472 (2005). This article characterizes the first bacterial CAMP-sensing regulation system.

  93. 93

    Jacoby, G. A. & Munoz-Price, L. S. The new β-lactamases. N. Engl. J. Med. 352, 380–391 (2005).

  94. 94

    Hiramatsu, K. Vancomycin-resistant Staphylococcus aureus: a new model of antibiotic resistance. Lancet Infect. Dis. 1, 147–155 (2001).

  95. 95

    van Veen, H. W. & Konings, W. N. Drug efflux proteins in multidrug resistant bacteria. Biol. Chem. 378, 769–777 (1997).

  96. 96

    Fux, C. A., Costerton, J. W., Stewart, P. S. & Stoodley, P. Survival strategies of infectious biofilms. Trends Microbiol. 13, 34–40 (2005).

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We would like to thank our co-workers and collaborators for help and support. Our research is supported by grants from the German Research Foundation, the European Union, the German Ministry of Education and Research, the IZKF program of the Medical Faculty, University of Tübingen, and the BONFOR program of the Medical Faculty, University of Bonn.

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Correspondence to Andreas Peschel.

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Entrez Genome Project

Enterococcus faecalis

Lactococcus lactis

Listeria monocytogenes

Neisseria gonorrhoeae

Neisseria meningitidis

Porphyromonas gingivalis

Proteus mirabilis

Pseudomonas aeurginosa

Salmonella enterica

Streptococcus agalactiae

Staphylococcus aureus

Streptococcus pyogenes


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A linear peptide that is also known as human cationic protein 18 (hCAP18). It is the only member of the cathelicidin family of antimicrobial peptides in humans.


A linear antimicrobial peptide produced by amphibians.


A linear antimicrobial peptide produced by insects and other invertebrates.


An antimicrobial peptide of diverse origin, usually adopting a sheet structure with three intramolecular disulphide bridges.


A porcine antimicrobial peptide with a sheet structure and two intramolecular disulphide bridges.

Cryptdin-related sequence (CRS) peptide

An antimicrobial peptide produced in the mouse intestine that forms disulphide-bridge-linked homo- or heterodimers.


An antimicrobial peptide produced by Gram-positive bacteria (bacteriocin), which contains lanthionine and/or methyllanthionine amino acids with thioether bridges.

Hepcidin-related CAMP

A vertebrate peptide with antimicrobial and iron-metabolism-regulating hormone-like activities.


An α-defensin produced by Paneth cells in the small intestine of mice.


An antimicrobial chemokine or chemokine-derived peptide from mammalian platelets.

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