Initial Protein Recovery Process
Recombinant proteins are one of the major products of the biotechnology industry. They are produced from a variety of sources including bacteria, yeast, mammalian and insect cells. Protein recovery and purification processes for clinical or diagnostic use employ similar approaches and methodologies, regardless of the protein source. These processes are lengthy and require considerable attention. The first step is the extraction of the targeted protein from the biological source, which can be media or biomass. The purpose of this step is to capture and concentrate the targeted protein by removing the liquids, and possibly removing contaminants; as a result it is feasible to further purify the protein according to its intended use. The methods available for the initial purification include centrifugation, filtration, cell disintegration, precipitation, extraction, and direct or indirect adsorption. Purification methods, specifically for pilot and mid scale processes, their advantages and disadvantages and examples, are described in this chapter.
About the Author
Biotechnology Unit, NIDDK NIH, Bethesda, MD
Dr. Joseph Shiloach is the director of the Biotechnology Unit at the National Institute of Diabetic digestive and kidney diseases, which is part of the National Institutes of Health. This multi-purpose facility is responsible for production and purification of biological products from prokaryotes and eukaryotes. The unit is involved both in the propagation phase of various cells and microorganisms and the recovery and purification phase of products which are needed for clinical evaluation and structural studies. The facility covers the research and development aspects as well as the pilot scale production aspects. Dr. Shiloach, a graduate of the Hebrew University, is currently focusing his research on developing new and improved methods for recombinant protein production, on investigating the metabolism of the producers and on integrating the upstream and down stream processes.