Chemical ecology of marine cyanobacterial secondary metabolites: A mini-review

More than 300 nitrogen-containing secondary metabolites have been reported from the procaryotic marine cyanobacteria. A majority of these compounds are of the polypeptide or mixed polyketide-polypeptide structural class and they are a potential source of novel pharmaceuticals. In spite of the chemical richness of marine cyanobacteria, not much is known regarding their ecological functions. To date only a handful of marine cyanobacterial compounds have been examined for their involvement in predator-prey interactions. This mini-review surveys the various chemical ecology studies conducted on marine cyanobacterial compounds. From these ecological studies, many marine cyanobacterial compounds are known to deter feeding by several species of marine predators. Such chemical defense may be crucial in maintaining the population of marine cyanobacterial bloom in nature. In addition, a series of ecological studies from our laboratory revealed the anti-settlement properties of a number of benthic marine cyanobacterial compounds. These studies suggested marine cyanobacteria as a potential source of natural antifoulants for the control of fouling organisms