Structural and catalytic aspects of cutinase in w/o microemulsions

Microemulsion systems for catalytic reactions and processes

This mini-review shows the diversity of microemulsion systems for catalytic reactions with the potential for process development.

Kinetics of reactions catalyzed by enzymes in solutions of surfactants

The effect of surfactants, both in water-in-oil microemulsions (hydrated reverse micelles) and aqueous solutions upon enzymatic processes is reviewed, with special emphasis on the effect of the surfactant upon the kinetic parameters of the process. Differences and similarities between processes taking place in aqueous and organic solvents are highlighted, and the main models currently employed to interpret the results are briefly discussed.

Enzyme catalysis in reverse micelles

Water in oil microemulsions with reverse micelles provide an interesting alternative to normal organic solvents in enzyme catalysis with hydrophobic substrates. Reverse micelles are useful microreactors because they can host proteins like enzymes. Catalytic reactions with water insoluble substrates can occur at the large internal water-oil interface inside the microemulsion. The activity and stability of biomolecules can be controlled, mainly by the concentration of water in these media. With the exact knowledge of the phase behaviour and the corresponding activity of enzymes the application of these media can lead to favourable effects compared to aqueous systems, like hyperactivity or increased stability of the enzymes.

Cutinase: from molecular level to bioprocess development

This review analyzes the role of cutinases in nature and their potential biotechnological applications. The cloning and expression of a fungal cutinase, Fusarium solani f. pisi, in Escherichia coli and Saccharomyces cerevisiae hosts are described. The three-dimensional structure of this cutinase is also analyzed and its function as a lipase is discussed and compared with other lipases. The biocatalytic applications of cutinase are described taking into account the preparation of different cutinase forms and the media in which the different types of reactions have been performed, namely hydrolysis, esterification, transesterification, and resolution of racemic mixtures. The stability of cutinase preparations is discussed and, in particular, the cutinase stability in anionic reversed micelles is analyzed considering the role of hexanol as a substrate, a cosurfactant, and a stabilizer. Process development, based on the operation of cutinase reactors, is also reviewed.