Voltage-gated potassium channel inhibitor that is certainly used for prey capture (PubMed:30109357). It inhibits several potassium channels, but not all (Kv1.1/KCNA1 (IC(50)=353 nM), Kv1.2/KCNA2 (IC(50)=146 nM), Kv1.3/KCNA3 (IC(50)=3051 nM), Kv1.6/KCNA6 (IC(50)=191 nM), and Shaker IR (23% inhibition at 3 uM)) (PubMed:30109357). In vivo, injection of this toxin into amphipods results in impaired swimming followed by contractile paralysis (PubMed:30109357). Expressed by tentacle. Adopts the three-dimensional structure 'proline-hinged asymmetric beta-hairpin-like' (PHAB) fold. The prepropeptide contains 10 domains separated by dibasic cleavage sites: a signal peptide, three cysteine-containing propeptide domains (CysPro), three cysteine-free propeptide domains (LinearPro) and three Kappa-actitoxin-Ate1a (PHAB) domains. The sequence 'CysPro-LinearPro-PHAB' is repeated three times. Monoisotopic mass. Does not show antimicrobial activity (when 256 ug/mL are tested on E.coli, K.pneumoniae, A.baumannii, P.aeruginosa, and S.aureus, as well as on fungi C.albicans and C.neoformans) (PubMed:30109357). Is not cytotoxic or cytolytic against cultured human cancer cell lines and erythrocytes (PubMed:30109357). It shows only a weak affinity for lipid membranes (PubMed:30109357). It has no effect on Kv1.4/KCNA4, Kv1.5/KCNA5, Kv2.1/KCNB1, Kv3.1/KCNC1, Kv4.2/KCND2, Kv7.2/KCNQ2, and Kv11.1/KCNH2/ERG1 (PubMed:30109357). Belongs to the sea anemonne PHAB family.