Development of a silicon carbide disruption method enables efficient extraction of proteins from cyanobacterium Synechocystis sp. PCC 6803

The oxygenic photosynthetic prokaryotes cyanobacteria have recently attracted worldwide interest in production of biofuels and bioactive natural compounds. Disruption of cells is a prerequisite for extraction of intracellular compounds. However, cyanobacterial cells are difficult to be disrupted because of the multiple-layered cell walls covered with a mucilaginous sheath. Here, we report a new disruption method for cyanobacteria, where an abrasive material, silicon carbide, is ground with cell pellet in situ. A cell disruption efficiency of 93.3 ± 2.3% was achieved in 6 min, an efficiency comparable to that obtained after 30 min of sonication. The new method yielded crude cell extracts with high concentrations of protein and high activity of the target enzyme, d-lactate dehydrogenase. This method has potential to be used for disruption of cells of photosynthetic microorganisms on a larger scale.