ISSN:
0730-2312
Keywords:
Casein micelle
;
Immunopurification
;
Lactation
;
Monoclonal antibody
;
Post-translational modification
;
proteases
;
therapeutics
;
viral inactivation
;
whey
;
Life and Medical Sciences
;
Cell & Developmental Biology
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Biology
,
Chemistry and Pharmacology
,
Medicine
Notes:
Milk is a complex bio-colloid which presents some unique problems for the protein isolation chemist, but the majority of the processing criteria for purifying recombinant proteins are the same as with any complex biological mixture. The casein micelles and fat globules behave as separate phases; they prevent filtration of the milk and interfere with the usual separation methods. The usual first step is to centrifuge the milk to remove the fat and precipitate the casein micelles with low pH or precipitating agents. Some recombinant proteins may associate to some degree with the micelles which may necessitate solubilizing them with chelating agents. If the majority of the product protein associates with either the fat or micelles, this can be used to advantage. Once the casein micelles have been removed or disrupted, the clarified milk can be processed by the usual separation methods. There also are proteases in milk which can degrade recombinant proteins. The greatest advantage of producing recombinant proteins in milk is the high concentration which can be obtained. The high levels of product protein can alleviate many problems associated with the application of classical purification strategies to transgenic milk proteins.
Additional Material:
1 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/jcb.240490403
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