Tailoring the Photoresponse of Photosynthetic Cyanobacteria (Synechococcus elongatus)*

Photosynthesis, especially by Synechococcus elongatus bacteria found in light-exposed freshwater, plays a crucial role in global carbon fixation and bioenergy production. These cyanobacteria, also known as blue-green algae, mainly absorb light in the blue ( 420-450nm) and red (640-680nm) regions but have a “green gap” in the region(500-550nm) of the spectrum. Despite this, their auxiliary phycobilisome pigments (phycoerythrin 570nm, phycocyanin 620nm, allophycocyanin 650nm) absorb light at different wavelengths of the green region making it efficient for photosynthesis. The distribution and dynamics of energy transfer components in cyanobacterial thylakoid membranes govern the regulation of electron transfer pathways in nature, this attracted attention to the exact energy transfer mechanism. To improve our understanding of the mechanism, there have been attempts to genetically modify these pigments. To circumvent this, we explored the binding of these pigments with specific peptides which quenched and enhanced the photo response of pigments by increasing quantum yield using simple extraction, and quantification with response to absorption and emission phenomenon by spectrophysical techniques of nanoscience without genetic alterations. We developed new methods to influence cyanobacteria photosynthesis, offering insights into energy transfer pathways contributing to a sustainable environment and combating global warming.