Effects of Inorganic Carbon on Cyanobacterial Phycobiliprotein Fluorescence

Cyanobacteria have the potential to be energy-efficient sources of biofuels and high-value chemicals. However, they are not currently viable as cell factories on industrial scales, because high-production strains need to be engineered. To unlock their industrial potential, one promising approach is to optimize their carbon-dioxide-based regulatory pathways. Previous research has demonstrated that reversible carbamylation of the phycobiliprotein allophycocyanin A of Synechocystis sp. PCC6803 regulates electronic energy transfer in the cyanobacterial phycobilisome. Using in vitro analysis of purified proteins, this study demonstrates that the phycobiliprotein c-phycocyanin may alsoexperience enhancement of energy transfer due to carbamylation mediated by elevated carbon dioxide concentrations.