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Melittin is the principal active component of apitoxin (bee venom) and is a powerful stimulator of phospholipase A2. Melittin is a peptide consisting of 26 amino acids with the sequence GIGAVLKVLTTGLPALISWIKRKRQQ.
Melittin inhibits protein kinase C, Ca2+/calmodulin-dependent protein kinase II, myosin light chain kinase and Na+/K+-ATPase (synaptosomal membrane) and is a cell membrane lytic factor. Melittin is a small peptide with no disulfide bridge; the N-terminal part of the molecule is predominantly hydrophobic and the C-terminal part is hydrophilic and strongly basic.
Extensive work with melittin has shown that the venom has multiple effects, probably, as a result of its interaction with negatively charged phospholipids. It inhibits well known transport pumps such as the Na+-K+-ATPase and the H+-K+-ATPase. Melittin increases the permeability of cell membranes to ions, particularly Na+ and indirectly Ca2+, because of the Na+-Ca2+-exchange. This effect results in marked morphological and functional changes, particularly in excitable tissues such as cardiac myocytes. In some other tissues, e.g., cornea, not only Na+ but Cl− permeability is also increased by melittin. Similar effects to melittin on H+-K+-ATPase have been found with the synthetic amphipathic polypeptide Trp-3.
Melittin also exhibits potent anti-microbial activity. For example, melittin has been shown to exert "profound inhibitory effects" on Borrelia burgdorferi, the bacteria that causes lyme disease. Melittin has also been shown to kill the yeast Candida albicans and to suppress Mycoplasma hominis and Chlamydia trachomatis infections.
Potential therapeutic applications
At Washington University School of Medicine in St. Louis, very small nanobot "nanobee" devices are being developed to carefully deliver melittin (which is known to disrupt cell membranes, and thus, destroy cells) to tumor cells in animals. In February 2013, it was reported that nanoparticles carrying melittin were effective in destroying HIV by eroding the double-layer viral envelope surrounding the virus. Possible applications include a vaginal gel that would target HIV intrusion prior to infection and as an intravenous treatment of extant HIV infections.
- Melitten - Compound Summary, PubChem.
- Yang S, Carrasquer G (January 1997). "Effect of melittin on ion transport across cell membranes". Zhongguo Yao Li Xue Bao. 18 (1): 3–5. PMID 10072885.
- Lubke LL, Garon CF (July 1997). "The antimicrobial agent melittin exhibits powerful in vitro inhibitory effects on the Lyme disease spirochete". Clin. Infect. Dis. 25 (Suppl 1): S48–51. doi:10.1086/516165. PMID 9233664.
- Klotz SA, Gaur NK, Rauceo J, Lake DF, Park Y, Hahm KS, Lipke PN (November 2004). "Inhibition of adherence and killing of Candida albicans with a 23-Mer peptide (Fn/23) with dual antifungal properties". Antimicrob. Agents Chemother. 48 (11): 4337–41. doi:10.1128/AAC.48.11.4337-4341.2004. PMC 525394. PMID 15504862.
- Lazarev VN, Shkarupeta MM, Titova GA, Kostrjukova ES, Akopian TA, Govorun VM (December 2005). "Effect of induced expression of an antimicrobial peptide melittin on Chlamydia trachomatis and Mycoplasma hominis infections in vivo". Biochem. Biophys. Res. Commun. 338 (2): 946–50. doi:10.1016/j.bbrc.2005.10.028. PMID 16246304.
- Lazarev VN, Stipkovits L, Biro J, Miklodi D, Shkarupeta MM, Titova GA, Akopian TA, Govorun VM (May 2004). "Induced expression of the antimicrobial peptide melittin inhibits experimental infection by Mycoplasma gallisepticum in chickens". Microbes Infect. 6 (6): 536–41. doi:10.1016/j.micinf.2004.02.006. PMID 15158186.
- Lazarev VN, Parfenova TM, Gularyan SK, Misyurina OY, Akopian TA, Govorun VM (February 2002). "Induced expression of melittin, an antimicrobial peptide, inhibits infection by Chlamydia trachomatis and Mycoplasma hominis in a HeLa cell line". Int. J. Antimicrob. Agents. 19 (2): 133–7. doi:10.1016/S0924-8579(01)00479-4. PMID 11850166.
- "The Buzz: Targeting Cancer With Bee Venom". Wall Street Journal. September 28, 2009.
- Hood JL, Jallouk AP, Campbell N, Ratner L, Wickline SA (2013). "Cytolytic nanoparticles attenuate HIV-1 infectivity". Antiviral Therapyapy. 18 (1): 95–103. doi:10.3851/IMP2346. PMID 22954649. Lay summary – Washington University in St. Louis (March 7, 2013).
- Verma N, Karmakar M, Singh KP, Smita S (February 2013). "Structural and Dynamic Insights into S100B Protein Activity Inhibition by Melittin for the Treatment of Epilepsy". International journal of Computer Application. NSAAILS (1): 55–60. ISSN 0975-8887.