Lysenin, a sphingomyelin-specific pore-forming toxin from earthworms; causes contraction of rat vascular smooth muscle. (Sekizawa et al., 1997; Shogomori and Kobayashi, 2007). Trp-20 is required for cation selective channel assembly (Kwiatkowska et al., 2007). Adenosine phosphates control the activity of lysenin channels inserted into planar lipid membranes with respect to their macroscopic conductance and voltage-induced gating. Addition of ATP, ADP, or AMP decreased the macroscopic conductance of lysenin channels in a concentration-dependent manner, with ATP being the most potent inhibitor and AMP the least (Bryant et al. 2016). lysenin can specifically interact with sphingomyelin, and may confer innate immunity against parasites by attacking the membranes of the parasites to form pores (Pang et al. 2019).
Lysenin of Eisenia foetida