Plant BioMEMs is a new field of cellular manipulation. The idea is to integrate plant cells into a Lab-on-Chip device to administer gradients or to combine different cell types by a microfluidic flow to simulate the interaction of cells in a real tissue. A promising application of this strategy is metabolic engineering. Metabolic engineering means that a metabolic pathway is diverted at branching points, either by blocking a branch (downregulation of a gene) or by activating a branch (upregulation of a key enzyme). Plants are extremely proficient with respect to secondary metabolism. Many of these metabolites are of medical interest. To produce them in cell culture (so called plant cell fermentation) would be promising. There is a drawback, however: plant cell cultures are reluctant to unfold their metabolic potency, because they consist of only one cell type - in real tissues, several cell types work together and produce different steps of the pathway, similar to the division of labour in a factory.
To find some background on the principles and applications of Plant BioMEMs refer to Ilias: Fakultät für Chemie und Biowissenschaften - current semester - BIO_MA_FOR_1201_Plant_Cell_Biology
Your task is now to work out a strategy, for one of our current projects (cephalotaxines in Cephalotaxus), a metabolic strategy based on the chip. As a first step, you must infer the metabolic pathways. The problem, we are currently struggling with, is not so much the enzymes from Cephalotaxus, but the behaviour of their host environment (tobacco BY-2 cells). Fortunately, the metabolism of tobacco is constructed and can be found in the KEGG database (information on how to find this, is given in the slides). There are now two strategies to cope with the problem that C3H of the tobacco host diverts part of the precursors to a shunt pathway in direction to ferulic acid (lignin precursor). Details are given in the slides and the movie found on the Ilias page.