LAUSR

Aldol reactions play an important role in organic synthesis, as they belong to the class of highly beneficial C-C-linking reactions. Aldol type reactions can be efficiently and stereoselectively catalyzed by the enzyme 2-Deoxy-D-ribose-5-phosphate aldolase (DERA) to gain key intermediates for pharmaceuticals like atorvastatin. The immobilization of DERA would open the opportunity for a continuous operation mode which gives access to an efficient, large-scale production of respective organic intermediates. In this contribution, we synthesize and utilize DERA/polymer conjugates for the generation and fixation of a DERA bearing thin film on a polymeric membrane support. The conjugation strongly increases the tolerance of the enzyme towards the industrial relevant substrate acetaldehyde while UV-crosslinkable groups along the conjugated polymer chains provide the opportunity for covalent binding to the support. First, we provide a thorough characterization of the conjugates followed by immobilization tests on representative, non-porous cycloolefinic copolymer supports. Finally, immobilization on the target supports constituted of polyacrylonitrile (PAN) membranes is performed and the resulting enzymatically active membranes are implemented in a simple membrane module setup for a first assessment of biocatalytic performance in continuous operation mode using the combination hexanal/acetaldehyde as substrate.