Structural highlights
Function
ACTP2_STIHL Pore-forming protein that forms cations-selective hydrophilic pores of around 1 nm and causes cardiac stimulation and hemolysis. Pore formation is a multi-step process that involves specific recognition of membrane sphingomyelin (but neither cholesterol nor phosphatidylcholine) using aromatic rich region and adjacent phosphocholine (POC) binding site, firm binding to the membrane (mainly driven by hydrophobic interactions) accompanied by the transfer of the N-terminal region to the lipid-water interface and finally pore formation after oligomerization of several monomers. Cytolytic effects include red blood cells hemolysis, platelet aggregation and lysis, cytotoxic and cytostatic effects on fibroblasts. Lethality in mammals has been ascribed to severe vasospasm of coronary vessels, cardiac arrhythmia, and inotropic effects.[1] [2]
References
- ↑ Lanio ME, Morera V, Alvarez C, Tejuca M, Gomez T, Pazos F, Besada V, Martinez D, Huerta V, Padron G, de los Angeles Chavez M. Purification and characterization of two hemolysins from Stichodactyla helianthus. Toxicon. 2001 Feb-Mar;39(2-3):187-94. PMID:10978735
- ↑ Martinez D, Campos AM, Pazos F, Alvarez C, Lanio ME, Casallanovo F, Schreier S, Salinas RK, Vergara C, Lissi E. Properties of St I and St II, two isotoxins isolated from Stichodactyla helianthus: a comparison. Toxicon. 2001 Oct;39(10):1547-60. PMID:11478962
