1.C.112 The Cubozoan Protein Toxin (CPT) Family

Class Cubozoa includes several species of box jellyfish that are harmful to humans and other animals. The venoms of box jellyfish are stored and discharged by nematocysts and contain a variety of bioactive proteins that are cytolytic, cytotoxic, inflammatory or lethal. Although cubozoan venoms generally share similar biological activities, the diverse range and severity of effects caused by different species indicate that their venoms vary in protein composition, activity and potency. Accumulating evidence suggests that cubozoan jellyfish produce at least one group of homologous bioactive proteins that are labile, basic, haemolytic and similar in molecular mass (42-46 kDa). Novel box jellyfish toxins are also potentially lethal and the cause of cutaneous pain, inflammation and necrosis. Secondary structure analysis and remote protein homology predictions suggest that the box jellyfish toxins may act as alpha-pore-forming toxins. The biological, biochemical and molecular characteristics of cubozoan venoms and their bioactive protein components were reviewed by Brinkman and Burnell 2009 with emphasis on cubozoan cytolysins and other box jellyfish toxins.