Transaminases are a family of enzymes with high potential in biotechnological applications. They can be very useful for the enantioselective production of a series of compounds with high value such as chiral amines and enantiopure amino alcohols which find use in many chemical fields; above all, for the synthesis of biologically active compounds. We have several of these enzymes (both S and R selective) and we have been successfully incorporated them in many flow-based project. 

Acyl-transferases are another very nice class of enzymes which is normally used to make esters. We have developed several projects on an acyl-transferase from Mycobacterium smegmatis which we have used for the scale up of the synthesis of melatonine (an amide) and flavour esters, and we designed a variant which accepts now also thiols for the synthesis of thirsters.  

Redox enzymes encompass a number of different biocatalysts of great industrial interest. We have a collection of enzymes from both salt adapted and mesophilic sources such as alcohol dehydrogenases (ADHs) and ketoreductases (KR) which we have used to synthesise chiral alcohols (in the reductive direction) and in the dynamic kinetic resolution of profenic aldehydes. NADH oxidases (NOXs) can then be combined with these enzymes for the recycling of the cofactor when the primary reaction is the oxidation of alcohols. We have also a nice imine reductase (ImR) which we employed in the synthesis of pipe colic acid.

Amino acid dehydrogenases are also redox enzymes which we use often in combination with other biocatalysts (transaminases for example, but also imine reductases, acyl-transferases etc) and have proven very useful in hydrogen-borrowing systems for the production of valuable chemicals.

Hydrolytic enzymes are another large family of very useful biocatalysts. A selection of esterases and amidases are now part of our library. In a separate project ß-glycosyl hydrolyses, all classified as GH1, have been selected to investigate how environmental adaptation affects biocatalytic properties, as well as stability at different temperatures, pHs and in the presence of solvents. We have looked at this enzymes also in the context of food chemistry applications, such as wine production and hydrolysis of valuable molecules from their glycol-conjugate form.

Cyclases are the latest addition to out lab, in collaboration with Prof. Hauer in Stuttgart we started working with these valuable (and challenging) membrane bound catalysts for the synthesis of precious fragrances.