Production and Purification of Recombinant Proteins

Protein targets which are analysed in biochemical assays are usually produced and purified from recombinant expression systems. CCS provides recombinant proteins from transfected mammalian cell lines or Baculovirus infected insect cells. Which expression system is most applicable for your project, depends on your particular goals and the characteristics of the protein.

For smaller volumes of up to several milligrams, a recombinant protein can be sufficiently expressed transiently in mammalian cells. We routinely use a serum free HEK293 cell line which is growing in suspension. These cells can be transfected with L-PEI in large scale very efficiently. For a more continuous supply of proteins the generation of a recombinant cell line based either on HEK293 or CHO-K1 is recommended. We are expanding stable production cell lines to harvest bulk amounts of cells or conditioned supernatant for further processing.

Proteins are purified by affinity or ion-exchange chromatography using an ÄKTATM FPLC system.  For your screening by ligand binding assay, we offer cell membranes in bulk quantities.

For your screening by ligand binding assay, we offer cell membranes in bulk. Cells are homogenized using nitrogen decompression, a very gentle method which does not heat the cells. Membranes are purified by a dual step high speed centrifugation protocol, and provided in aliquots which suit the requirement of your assay. The quality of membrane preparations is controlled in radio-ligand binding assays.