Proteolysis of recombinant proteins in bioengineered plant cells.

Plants are increasingly used as alternative expression hosts for the production of recombinant proteins offering many advantages including higher biomass and the ability to perform post-translational modifications on complex proteins. Key challenges for optimized accumulation of recombinant proteins in a plant system still remain, including endogenous plant proteolytic activity, which may severely compromise recombinant protein stability. Several strategies have recently been applied to improve protein stability by limiting protease action such as recombinant protein production in various sub-cellular compartments or application of protease inhibitors to limit protease action. A short update on the current strategies applied is provided here, with particular focus on sub-cellular sites previously selected for recombinant protein production and the co-expression of protease inhibitors to limit protease activity.