Microcystin biosynthesis and toxic effects

Population growth and its associated pressure on agricultural, urban, and industrial development have increased the incidence of harmful algal blooms. Microcystins are toxins produced by a variety of bloom-forming cyanobacteria that can cause hepatotoxicity in humans and animals. In this review article, we summarize progress in the understanding of microcystin biosynthesis and the effects of this toxin on surrounding organisms. We also present possible directions for further understanding the basic biology of microcystin biosynthesis. In particular, heterologous synthesis of microcystins in model cyanobacteria based on photosynthesis through the synthetic biology techniques will be an important step towards clarifying how microcystins are produced, how their synthesis is regulated, and how toxicity is produced in neighboring photosynthetic algae. The information presented here serves as a reference both for algal researchers and policymakers involved in setting future directions in microalgal research, particularly pertaining to microalgal-based microcystin biosynthesis.