Homogeneous Biocatalysis in Organic Solvents and Water-Organic Mixtures

摘要: Biocatalysis in non-aqueous media has undergone tremendous development during the last decade, and numerous reactions have been introduced optimized for synthetic applications. In contrast to aqueous enzymology, biotransformations organic solvents offer unique industrially attractive advantages, such as: drastic changes enantioselectivity of reaction, reversal thermodynamic equilibrium hydrolysis reactions, suppression water-dependent side resistance bacterial contamination. Currently, field is dominated by heterogeneous biocatalysis based primarily on lyophilized enzyme powders, cross-linked crystals, enzymes immobilized inert supports that are mainly applied enantioselective synthesis. However, low reaction rates an inherent problem biocatalysis, while homogeneous systems advantage elimination diffusional barriers substrates products between water phases results increase rate. Here discussion focused correlation activity structure intact dissolved neat solvents, as well modifications natural enzymes, which make them soluble catalytically active environment. Factors influence conformation stability also discussed. Current developments biocatalysts combine advantages protein modification immobilization, i.e., HIP plastics, chips, ionic liquids, introduced. Finally, engineering non-conventional directed evolution summarized.