Photosynthetica 2013, 51(2):215-220 | DOI: 10.1007/s11099-013-0018-1

A newly developed SGB buffer greatly enhances energy transfer efficiency from phycobilisomes to photosystem II in cyanobacteria in vitro

L. P. Chen^1,2, Q. X. Wang^1,2,*, W. M. Ma^1,*

¹ School of Life Science, East China Normal University, Shanghai, China

² College of Life and Environment Sciences, Shanghai Normal University, Shanghai, China

The transfer of light energy from phycobilisomes (PBS) to photosystem II (PSII) reaction centers is vital for photosynthesis in cyanobacteria and red algae. To investigate the relationship between PBS and PSII and to optimize the energy transfer efficiency from PBS to PSII, isolation of the PBS-PSII supercomplex is necessary. SPC (sucrose/phosphate/citrate) is a conventional buffer for isolating PBS-PSII supercomplex in cyanobacteria. However, the energy transfer occurring in the supercomplex is poor. Here, we developed a new buffer named SGB by adding 1M glycinebetaine and additional sucrose to SPC buffer. Compared to SPC, the newly developed SGB buffer greatly enhanced the associated populations of PBS with thylakoid membranes and PSII and further improved the energy transfer efficiency from PBS to PSII reaction centers in cyanobacteria in vitro. Therefore, we conclude that SGB is an excellent buffer for isolating the PBS-PSII supercomplex and for enhancing the energy transfer efficiency from PBS to PSII reaction centers in cyanobacteria in vitro.

Keywords: energy transfer efficiency; photosystem II; phycobilisome; SGB buffer; Synechocystis sp. PCC 6803; thylakoid membrane

Received: January 3, 2012; Accepted: December 5, 2012; Published: June 1, 2013Show citation