Abstract

Whole-cell Biotransformations within the Microflow Systems

Polona Žnidaršic Plazl, Professor, University of Ljubljana

Whole-cell biocatalysis offers several benefits over the use of the purified enzymes, primarily due to the elimination of costs for biocatalyst isolation, the ability of cofactor regeneration and the possibility to perform complex cascade reactions based on existing or engineered metabolic pathways within the cells in one single process step. Immobilization of whole cells enables establishment of continuous bioprocesses with a long-term use of the same biocatalyst, which again contributes to lower production costs. As stated in several review papers, microflow reactors are promising tools both for early stages of the biocatalytic process development, as well as for the final production using the concept of numbering-up. This lecture will focus on development of efficient microflow reactors using whole cells for selected biotransformations. Various methods of cell immobilization in microchannels will be discussed, including covalent attachment on microchannel surfaces, magnetic-field assisted immobilization and the possibility to use microflow systems to prepare microbeads with entrapped cells. Benefits of using miniaturized devices for the optimization of process parameters with the aim to establish efficient continuous biotransformations will be highlighted.