Melittin is the main component (40–60% of the dry weight) and the major pain-producing substance of honeybee (Apis mellifera)venom. Melittin is a basicpeptide consisting of 26amino acids.[2]
| Melittin | |||||||||
|---|---|---|---|---|---|---|---|---|---|
 Melittin | |||||||||
| Identifiers | |||||||||
| Symbol | Melittin | ||||||||
| Pfam | PF01372 | ||||||||
| InterPro | IPR002116 | ||||||||
| SCOP2 | 2mlt /SCOPe /SUPFAM | ||||||||
| TCDB | 1.C.18 | ||||||||
| OPM superfamily | 151 | ||||||||
| OPM protein | 2mlt | ||||||||
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| Identifiers | |
|---|---|
3D model (JSmol) | |
| ChEBI | |
| ChEMBL | |
| ChemSpider |
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| ECHA InfoCard | 100.157.496 |
| MeSH | Melitten |
| UNII | |
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| Properties | |
| C131H229N39O31 | |
| Molar mass | 2846.46266 |
Except where otherwise noted, data are given for materials in theirstandard state (at 25 °C [77 °F], 100 kPa). | |
Function
editThe principal function of melittin as a component ofbee venom is to cause pain and destruction of tissue of intruders that threaten a beehive. However, in honey bees, melittin is not onlyexpressed in the venom gland, but also in other tissues when infected with pathogens. The two venom molecules, melittin andsecapin, that are over-expressed in honey bees infected with various pathogens, possibly indicate a role for melittin in theimmune response of bees toinfectious diseases.[3]
Structure
editMelittin is a smallpeptide with nodisulfide bridge; theN-terminal part of themolecule is predominantlyhydrophobic and theC-terminal part ishydrophilic and stronglybasic. In water, it forms atetramer but it also can spontaneously integrate itself into cell membranes.[4]
Mechanism of action
editInjection of melittin into animals and humans causes pain sensation. It has strong surface effects on cell membranes causing pore-formation inepithelial cells and the destruction ofred blood cells. Melittin also activatesnociceptor (pain receptor) cells through a variety of mechanisms.[2]
Melittin can open thermal nociceptorTRPV1 channels viacyclooxygenase metabolites resulting in depolarization of nociceptor cells. The pore forming effects in cells causes the release of pro-inflammatory cytokines. It also activatesG-protein-coupled receptor-mediated opening oftransient receptor potential channels. Finally melittin up-regulates the expression ofNav1.8 andNav1.9 sodium channels in nociceptor cell causing long term action potential firing and pain sensation.[2]
Melittininhibitsprotein kinase C, Ca2+/calmodulin-dependent proteinkinase II,myosinlightchain kinase, and Na+/K+-ATPase (synaptosomal membrane). Melittinblockstransport pumps such as the Na+-K+-ATPase and the H+-K+-ATPase.[2]
Toxicity of a bee sting
editMelittin is the main compound in bee venom, accounting for the potentiallethality of a bee sting, which causes ananaphylactic reaction in some people.[5] At the sites of multiple stings, localized pain, swelling, andskin redness occur, and if bees are swallowed, life-threatening swelling of thethroat and respiratory passages may develop.[5]
Use
editBee venom therapy has been used intraditional medicine for treating various disorders,[6] although its non-specifictoxicity has limitedscientific research on its potential effects.[7]
References
edit- ^Melitten - Compound Summary,PubChem.
- ^abcdChen J, Guan SM, Sun W, Fu H (2016)."Melittin, the Major Pain-Producing Substance of Bee Venom".Neuroscience Bulletin.32 (3):265–272.doi:10.1007/s12264-016-0024-y.PMC 5563768.PMID 26983715.
- ^Doublet V, Poeschl Y, Gogol-Döring A, Alaux C, Annoscia D, Aurori C, et al. (March 2017)."Unity in defence: honeybee workers exhibit conserved molecular responses to diverse pathogens".BMC Genomics.18 (1): 207.doi:10.1186/s12864-017-3597-6.PMC 5333379.PMID 28249569.
- ^Terwilliger TC, Eisenberg D (1982)."The structure of melittin. II. Interpretation of the structure"(PDF).The Journal of Biological Chemistry.257 (11):6016–6022.doi:10.1016/S0021-9258(20)65098-0.PMID 7076662.
- ^ab"Bee venom". Drugs.com. 2 March 2024. Retrieved15 July 2024.
- ^Rady I, Siddiqui IA, Rady M, Mukhtar H (2017)."Melittin, a major peptide component of bee venom, and its conjugates in cancer therapy".Cancer Letters.402:16–31.doi:10.1016/j.canlet.2017.05.010.PMC 5682937.PMID 28536009.
- ^Liu CC, Hao DJ, Zhang Q, An J, Zhao JJ, Chen B, Zhang LL, Yang H (2016). "Application of bee venom and its main constituent melittin for cancer treatment".Cancer Chemotherapy and Pharmacology.78 (6):1113–1130.doi:10.1007/s00280-016-3160-1.PMID 27677623.S2CID 12596298.
External links
edit- Melitten at the U.S. National Library of MedicineMedical Subject Headings (MeSH)