8.B.3.1.9
 GsMTx4 of 82 aas and one N-terminal TMS.  This cationic hydrophobic peptide inhibits a lot of different Na⁺ and K⁺ channels and has antimicrobial activity (Gnanasambandam et al. 2017). It blocks mechanosensitive ion channels (also named stretch-activated channels or SACs), without having effect on whole-cell voltage-sensitive currents. Acts by partitioning into the membrane and perturbing the interface between the channel and the lipid bilayer without necessarily being in physical contact with the channel. Inhibits atrial fibrillation as well as the membrane motor of outer hair cells at low doses. It also binds to the voltage sensor of voltage-gated potassium channels from the archaebacterium Aeropyrum pernix (KvAP) without affecting channel gating. The presence of a 'disulfide through disulfide knot' structurally defines this protein as a knottin (Gnanasambandam et al. 2017).