Protein separation effect

Hanson, M., Unger, K. K., Mant, C. T., and Hodges, R. S., Polymer-coated reversed-phase packings with controlled hydrophobic properties. I. Effect on the selectivity of protein separations, /. Chromatogr., 599, 65, 1992. 

Nimura, N., Itoh, H., Kinoshita, T., Nagae, N., Nomura, M. (1991). Fast protein separation by reversed-phase high-performance liquid-chromatography on octadecylsilyl-bonded non-porous silica-gel — effect of particle-size of column packing on column efficiency. J. Chromatogr. 585(2), 207-211. 

Figure 7.7. Results from model simulations showing the effect of protein separation and the effect of MS detection limit and MS dynamic range on the success rate and the relative dynamic range (RDR) for detection of proteins from H. sapiens tissue samples. (See page 219 for text discussion.)...

An example of the effect of pore size on the separation of a set of native proteins is shown in Figure 8.4. The 4%T, 2.67%C gel shown on the left is essentially nonsieving. Proteins in the artificial sample migrate in the gel more or less on the basis of their free mobility. The 8%T, 2.67%C gel on the right sieves the proteins shown and demonstrates the combined effects of charge and size on protein separation. The relative positions of some proteins are shifted in the sieving gel as compared to the nonsieving one. 

In the RNase-S system, early studies showed loss of potential activity of S-peptide and S-protein separately on photooxidation 152). Histidine 12 was thus immediately implicated in the activity. Subsequently, a more careful study showed that loss of His 119 resulted in loss of activity but oxidation of 105 had no effect on activity 153). Histidine 48 was apparently not accessible to photooxidation. Photooxidation of His 12 in S-peptide markedly reduced the binding constant to S-protein. 

Each protein has a characteristic salting-out point, a fact we can exploit to make protein separations in crude extracts. For this purpose (NH4)2S04 is the most commonly used salt because it is very soluble and is generally effective at lower concentrations than many other salts. 

It is one of the most effective methods of protein separation and characterization. The chief advantages of this method are that it can be performed under very mild conditions and it has high resolving power, resulting in the clear separation of similarly charged protein molecules. However, in order to use this separation technique, the components of a mixture must have an ionic form, and each component must possess a different net charge. 

Fraser, R. Clay, C. (1983). Pathogenesis-related proteins and acquired resistance causal relationship or separate effects. Netherlands Journal of Plant Pathology 89, 283-92. 

Fig. 7.10. Electrochromatogram of protein separation on an etched diol-modified capillary. L (total capillary length) = 45 cm, 1 (effective capillary length) = 25 cm, i.d. = 50 pm, V = 22 kV, i = 7 pm, pH = 4.41. Solutes 1 = cytochrome c 2 = lysozyme (turkey) 3 = myoglobin and 4 = ribonuclease A.

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