Microcystins—or cyanoginosins—are a class of toxins produced by certain cyanobacteria, commonly known as blue-green algae.[3] Over 250[4] different microcystins have been discovered so far, of which microcystin-LR is the most common. Chemically they are cyclic heptapeptides produced through nonribosomal peptide synthases.[5]
Cyanobacteria can produce microcystins in large quantities during algal blooms which then pose a major threat to drinking and irrigation water supplies, and the environment at large.[6][7]