CN-PAGE, thermostability, barley, spruce

The central aim of our study was to develop a method for solubilization and native electrophoretic (colourlessnative polyacrylamide gel electrophoresis; CN-PAGE) separation of pigment-protein complexes (PPCs) embeddedin thylakoid membranes (tBMs) isolated from spruce. Subsequently, we focused on studying the effectof temperature on the composition and PPC stability of two different species: barley and spruce.We found that the mild detergent n-dodecyl ?-D-maltoside (?-DM) is suitable for PPC solubilization of spruce tBMs, but longer solubilization and a higher ratio of detergent to total chlorophyll are needed forspruce than are needed for barley. We also unified CN-PAGE protocols to optimize the separation of spruce and barley PPCs that resulted in the separation of photosystem I (PSI) and photosystem II (PSII) supercomplexes(SCs), PSI and PSII core dimers, PSII core monomers, trimeric and monomeric light-harvesting complexes of PSII, and bands with free pigments.