Adaptation and Regulation of Photosynthetic Apparatus in Response to Light

Solar light can be efficiently captured and converted into chemical energy by all phototrophs, including photosynthetic bacteria, cyanobacteria, algae, and vascular plants, through their specific photosynthetic machinery. The major environmental challenge to photosynthetic organisms is the variability in the light. To cope with the rapidly fluctuating light environment (specifically in intensity and wavelength distribution), the phototrophs have evolved complex regulatory systems to adapt to changing light conditions. Advanced understanding of the adaptive mechanisms developed by photosynthetic organisms will inform the bioengineering of phototrophs to enhance the utilization of solar energy, for the production of biofuel and commodity products from light, CO₂, and water. In this chapter, we will summarize recent studies on the molecular basis underlying the physiological adaptation and regulation of photosynthetic machinery, in particular, in cyanobacteria, toward irradiance variation.