Protein methodology: general methods

Protein Functional Methodology - Outline of General Methods... 

Having discussed the staining of cells for both extracellular and intracellular proteins, and, in the process, learned something about general flow cytometric methodologies for analysis of data, we are now ready, in the next chapter, to apply some of these general methods to cellular components that are not proteins at all. 

Gel electrophoresis is widely used in the routine analysis and separation of many well-known biopolymers such as proteins or nucleic acids. Little has been reported concerning the use of this methodology for the analysis of synthetic polymers, undoubtedly since in many cases these polymers are not soluble in aqueous solution - a medium normally used for electrophoresis. Even for those water-soluble synthetic polymers, the broad molecular weight dispersities usually associated with traditional polymers generally preclude the use of electrophoretic methods. Dendrimers, however, especially those constructed using semi-controlled or controlled structure synthesis (Chapters 8 and 9), possess narrow molecular weight distribution and those that are sufficiently water solubile, usually are ideal analytes for electrophoretic methods. More specifically, poly(amidoamine) (PAMAM) and related dendrimers have been proven amendable to gel electrophoresis, as will be discussed in this chapter. 

The most commonly used culture system for scale-up of E. coli is the shake flask. This conventional methodology has been shown to produce the quantity and quality of protein required with good scalability from plate-based expression screening. In general, cell-line, medium, growth conditions, and induction method are determined by the small-scale expression screen. Typically, the shake-flask is filled to one-quarter of its capacity to allow for adequate aeration of the culture. The generic OPPF... 

As previously alluded to, functional methodology is not, as yet, fully standardized. The literature is bulging with methods, many times improvised on the spur of the moment to fit the needs and instruments of the researcher, with inadequate preliminary examination or statistical evaluation. This section will attempt to organize a general system of methodology for protein food products. In it, a general plan of assays will be followed by criteria for choice of assay, characteristics of Model Tests, and, finally, characteristics of Utility Tests. 

In a previous section some general functional properties that are commonly looked for in protein products were classified according to physico-chemical properties. In this section, the general methodology for the objective evaluation (excluding sensory subjective methods), of these properties will be outlined. 

Three general methodologies for photoregulating such activities of biomaterials as catalytic, binding, or recognition functions have been suggested (Scheme 2). One method involves the tethering of photoisomerizable units to a protein (Scheme 2(A)). In one photoisomer state, state A, the tertiary structure of the protein is... 

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