Lysate processing filtration steps

To answer the above issues, a model system was devised in which a specific protein was added to ah IS. coll lysate. The lysate was then processed through the filtration steps and the protein recovered. The protein chosen was human IgG which has a relatively large molecular weight (160,000 Daltons). It was reasoned that if a large protein could be separated from cell debris and passed through a membrane and recovered, then a smaller protein that is typical of a recombinant process, should prove to be much easier. 

Figure 2. Filtration steps for processing lysate. All steps, except the protein concentration, use a microporous membrane. Protein concentration is accomplished by a UF membrane.

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