Protein production, application

Advances in soy protein processing technology have allowed extensive diversification of protein product applications. More sophisticated soy protein products now manufactured have more functionality, better performance, more consistency and better flavor than commercially available defatted soy flour and grits (50% protein dry basis). Among these products are improved textured soy flours, concentrates, and isolates (50%, 70% and 90% protein dry basis, respectfully), functional and non-functional soy protein concentrates (70% protein dry basis) and highly soluble, highly functional isolated soy proteins (90% protein dry basis) (6-8 14-18). 

At the moment, most of these more exotic bacteria are mainly used in expression for fundamental studies. Considering the speed of developments in biotechnology, their application for industrial or pharmaceutical protein production might become even more important very soon. 

Steinborn, G., Boer, E., Scholz, A. et al. (2006) Application of a wide-range yeast vector (CoMed) system to recombinant protein production in dimorphic Arxula adeninivorans, methylotrophic Hansenula polymorpha and other yeasts. Microbial Cell Factories, 5, 33. 

Several molecular strategies have been successful in increasing foreign protein production in cultured plant cells. These include using promoters for inducible expression [10, 12, 29], optimizing codon usage [30] and adding the KDEL sequence to ensure protein retention in the endoplasmic reticulum [31]. Application of different... 

As gelatin is a common food additive with applications in the pharmaceutical industry, its introduction into foreign protein production systems may generate fewer regulatory concerns than other biopolymers. 

Reverse-phase HPLC (RP-HPLC) separates proteins on the basis of differences in their surface hydophobicity. The stationary phase in the HPLC column normally consists of silica or a polymeric support to which hydrophobic arms (usually alkyl chains, such as butyl, octyl or octadecyl groups) have been attached. Reverse-phase systems have proven themselves to be a particularly powerful analytical technique, capable of separating very similar molecules displaying only minor differences in hydrophobicity. In some instances a single amino acid substitution or the removal of a single amino acid from the end of a polypeptide chain can be detected by RP-HPLC. In most instances, modifications such as deamidation will also cause peak shifts. Such systems, therefore, may be used to detect impurities, be they related or unrelated to the protein product. RP-HPLC finds extensive application in, for example, the analysis of insulin preparations. Modified forms, or insulin polymers, are easily distinguishable from native insulin on reverse-phase columns. 

The application of the improved MS techniques presented above with highly resolving separation methods, such as 2-D electrophoresis, capillary HPLC, and CE, resulted in the creation of a new science, proteomics63 While genomics, described by DNA databases, represents the ground stage of the cell, the study of the differential status of the cell, due to various stimuli or disease states, reflects the functional expression of protein products or proteomics. Proteomics studies are aimed at identifying the proteome, the network of proteins that define the... 

The successful application of CE technology has resulted in dramatic growth of CE as an essential tool for protein characterization, R D, and QC of therapeutic biomolecules. CE methods have clearly been shown to be superior over traditional slab-gel methods. Many biopharmaceutical companies have adopted CE techniques in QC environments for determination of product purity, identity and consistency needed for the release of protein products. The success of validation per ICH guidelines has moved CE technology to a position of greater prominence and ensures the quality release of therapeutic proteins and antibodies. 

Baldi, L., Muller, N., Picasso, S., Jacquet, R., Girard, P., Thanh, H. R, et al. (2005). Transient gene expression in suspension HEK-293 cells application to large-scale protein production. Biotechnol. Prog. 21,148-153. 

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