Photosynthesis

Photosynthesis is the complex biological process by which plants, algae, and certain bacteria convert light energy into chemical energy, stored in the form of organic molecules like glucose. The process is divided into light-dependent reactions, which occur in the thylakoid membranes and produce oxygen, ATP, and NADPH, and light-independent reactions (the Calvin cycle), which take place in the stroma and fix atmospheric carbon dioxide into sugar. While photosynthesis is not a therapeutic target in human medicine, it is a primary target for agricultural herbicides. These chemicals typically disrupt the photosynthetic electron transport chain or inhibit key enzymes like RuBisCO, leading to the accumulation of reactive oxygen species and the eventual death of the organism. Understanding the molecular mechanisms of photosynthesis is critical for improving crop yields and managing environmental health.

Other names

Carbon fixationLight-dependent reactionsLight-independent reactionsCalvin cyclePhotoautotrophy

Drugs targeting components of photosynthesis (primarily herbicides) typically act by binding to the D1 protein of Photosystem II to block electron transport, or by diverting electrons from Photosystem I to generate reactive oxygen species that cause rapid cellular lipid peroxidation and death.