Biocatalysis in Polymersomes: Improving Multienzyme Cascades with Incompatible Reaction Steps by Compartmentalization

Incompatibilities encountered in multienzyme syntheses often arise from inhibition or inactivation of individual enzymes by low-molecular-mass compounds. Polymersomes have the tremendous yet unproven potential to enhance the performance of cascade reactions by spatial separation of enzymes from the respective source of incompatibility. A main challenge is the requirement to reduce mass-transport limitations across the polymer membrane with sufficient selectivity to maintain the compartmentalization. We demonstrate that cross-inhibitions in cascade reactions can be avoided by reconstituting highly selective channel proteins into the membrane. Thus, the three-step synthesis of CMP- N -acetylneuraminic acid was improved 2.2-fold compared to the noncompartmentalized reaction.