Abstract
Biochemical and biological properties of 30 cytolytic polypeptide toxins isolated from 18 species of sea anemones (Actiniaria) are presented and classified into three groups according to their molecular mass, isoelectric points and the molecular mechanism of action. Phospholipase A2-like toxins (30 kDa) from Aiptasia pallida are dissimilar to acidic metridiolysin (80 kDa) from Metridium senile and the group of about 27 predominantly basic toxins, having a molecular mass of 16-20 or 10 kDa, inhibited by sphingomyelin. They are lethal for both invertebrates and vertebrates, cardiotoxic, cytolytic and cytotoxic. Pharmacological activities, cytotoxic and cytolytic properties are mediated, at least in part, by forming pores in lipid membranes. Channels, 1-2 nm in diameter, formed in planar lipid membranes are cation selective and rectified. The mechanisms and some characteristics of ion channel formation by the toxins in the cells as well as in artificial lipid membranes are summarized and discussed in view of the structure-function studies of the toxins. Putative biological roles of toxins, based on their channel-forming activity, in the capture and killing of prey, digestion, repelling of predators and intraspecific spatial competition are suggested.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
