Electrofocusing

Purified by Sephadex G-200 filtration and DEAE-cellulose column chromatography. Hexosaminidase A was further purified by DEAE-cellulose column chromatography, followed by an ECTEOLA-cellulose column, Sephadex-200 filtration, electrofocusing and Sephadex G-200 filtration. Hexosaminidase B was purified by a CM-cellulose column, electrofocusing and Sephadex G-200 filtration. [Srivastava et al. 7 Biol Chem 249 2034 1974.]... 

The deletion of pelX and of the five major pel genes from the E. chrysanthemi chromosome failed to totally eliminate the capadty for tissue maceration (16). Analysis of the macerated tissue by electrofocusing followed by an activity detection, revealed the presence of a new set of pectate lyases (up to 5 forms). Because of their low activity in synthetic medium, they were described as secondary pectinases. The gene of one secondary endo-pectate lyases, PelL, has been characterized in two E. chrysanthemi strains. The pelL gene of E. 

Bertheau, Y., Madgidi-Hervan, E., Kotoujansky, A., NguyenThe, C., Andro, T. and Coleno, A. 1984. Detection of depolymerase isoenzymes after electroporesis or electrofocusing... 

Electrofocusing can also be done in tubes, and this configuration once constituted the first dimension of 2-D PAGE.73 Because of difficulties in handling and reproducibility with tube gels, IPG strips have largely replaced them. 

Hjelmeland, L.M., Chrambach, A. (1981). Electrophoresis and electrofocusing in detergent containing media A discussion of basic concepts. Electrophoresis, 2, 1-11. 

Janolino, V. G. and Swaisgood, H. E. 1984. Isolation, solubilization, fractionation by electrofocusing, and immobilization of skim milk membranes. J. Dairy Sci. 67, 1161-1168. 

Mather, I. H. 1978. Separation of the proteins of bovine milk-fat globule membrane by electrofocusing. Biochim. Biophys. Acta 514, 25-36. 

Sullivan, C. H., Mather, I. H., Greenwalt, D. E. and Madara, P. J. 1982. Purification of xanthine oxidase from the fat-globule membrane of bovine milk by electrofocusing. Determination of isoelectric points and preparation of specific antibodies to the enzyme. MoL Cell. Biochem. 44, 13-22. 

The isoelectric point, determined by Sumner and Hand (50) to have a value of 5.0-5.1, has been redetermined by the electrofocusing technique (43). The value obtained was 4.8. The solubility is extremely small at this pH, but the urease can be located by its enzymic action. It is a point of interest that the solubility of the isoelectric species increases spectacularly if the sulfhydryl groups are substituted with A-ethylmaleimide (NEM) (43). 

Figure 4. Gel electrofocusing of T. koningii cellulose (A, left), and Ct (B, right) in an ampholyte covering the pH range 3,5-5.6. Ct was isolated as in Figure 1 and purified by further chromatography on DEAE-Sephaaex (6).

De Nobili, M. (1988). Electrophoretic evidence of the integrity of humic substances separated by means of electrofocusing. J. Soil Sci. 39,437-445. 

Figure 7. Electrofocusing pattern (top panel) and gel electrophoretic patterns (bottom panel) for the anti-gal isoantibodies (20 j...

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