Marine toxins for natural products drug discovery

Abstract

The production of toxins from marine animals is an important strategy that guarantees their survival in a highly competitive and challenging ecosystem. These animals produce an enormous number of metabolites, whose combinations result in a great variety of chemical structures and complex molecules, as alkaloids, steroids, peptides, and proteins with chemical and pharmacological properties that are entirely different from the terrestrial animal venoms (Russel 1971). Further, the biological properties of the venoms of terrestrial animals such as snakes, spider, and scorpions have been extensively investigated. The venomous invertebrates have developed, through their adaptive evolution, a huge number of toxins having, in each case, a single scaffold. They have evolved highly refined specificity and selectivity in targeting different types of ion channels and receptors (Kordis and Gubensek 2000). However, less research has been undertaken on marine creatures; this is due to the difficulties of obtaining and storing the venom extract and their extreme liability. The marine toxins are inevitable source of novel compounds due to the diversity of marine organisms and their competitive living habitat. These strategies have produced many valuable drugs and are likely continue to produce lead molecules for chemotherapeutic in future. Invertebrate venoms have attracted considerable interest as a potential source of bioactive compounds, especially neurotoxins and cardiotoxins. These molecules have proved to be extremely useful tools for the understanding of synaptic transmission events, ion channel blockers, and they have contributed to the design of novel drugs for the various medicinal purposes (Mortai et al. 2007).