anaphylatoxins
Sign in to saveAlso known as anaphylatoxin
Anaphylatoxins, or complement peptides, are fragments (C3a, C4a and C5a) that are produced as part of the activation of the complement system. Complement components C3, C4 and C5 are large glycoproteins that have important functions in the immune response and host defense. They have a wide variety of biological activities and are proteolytically activated by cleavage at a specific site, forming a- and b-fragments. A-fragments form distinct structural domains of approximately 76 amino acids, coded for by a single exon within the complement protein gene. The C3a, C4a and C5a components are refer
Key facts
- Protein family.Symbol
- ANATO
- Protein family.Name
- Anaphylotoxin-like domain
- Protein family.image
- PDB 1c5a EBI.jpg
- Protein family.caption
- Structure of porcine C5adesArg.
- Protein family.Pfam
- PF01821
- Protein family.InterPro
- IPR000020
- Protein family.SMART
- ANATO
- Protein family.Prosite
- PDOC00906
- Protein family.SCOP
- 1c5a
- Protein family.PDB
- B:693-728 :21-55 A:698-732 698-732
via Wikipedia infobox
Research
6,152 papers- Anaphylatoxins spark the flame in early autoimmunity.Frontiers in immunology · 2022
- Unveiling anaphylatoxins: Pioneering cancer therapies through complement system insights.Biochimica et biophysica acta. Reviews on cancer · 2025
- Complement anaphylatoxins C3a and C5a: Emerging roles in cancer progression and treatment.Seminars in cell & developmental biology · 2019
- Complement anaphylatoxins: Potential therapeutic target for diabetic kidney disease.Diabetic medicine : a journal of the British Diabetic Association · 2025
- Structure and function of the anaphylatoxins.Springer seminars in immunopathology · 1984
via PubMed
~3 min read
Encyclopedic overview
8 sectionsContents
- Function
- Examples
- Terminology
- Human proteins containing this domain
- See also
- References
- Further reading
- External links
Anaphylatoxins, or complement peptides, are fragments (C3a, C4a and C5a) that are produced as part of the activation of the complement system. Complement components C3, C4 and C5 are large glycoproteins that have important functions in the immune response and host defense. They have a wide variety of biological activities and are proteolytically activated by cleavage at a specific site, forming a- and b-fragments. A-fragments form distinct structural domains of approximately 76 amino acids, coded for by a single exon within the complement protein gene. The C3a, C4a and C5a components are referred to as anaphylatoxins: they cause smooth muscle contraction, vasodilation, histamine release from mast cells, and enhanced vascular permeability. They also mediate chemotaxis, inflammation, and generation of cytotoxic oxygen radicals. The proteins are highly hydrophilic, with a mainly alpha-helical structure held together by 3 disulfide bridges.
== Function ==
Excerpted from Wikipedia’s “anaphylatoxins” article, available under the CC BY-SA 4.0 licence.