Dehydrogenases starch electrophoresis

NADPH-specific isocitric dehydrogenase shows at least 3, and probably 4, bands separable by starch gel electrophoresis in normal epidermis (F25, 03) whereas in psoriatic skin the most anodal bands disappear (F26) (Fig. 11). They reappear with treatment of the lesion. Basal cell carcinoma also shows no activity of this anodal band. We think the most anodal band is somehow linked to normal keratinization since the basal cell carcinoma has a rate of proliferation which is not much faster... 

Isoenzymes have usually been separated by zone electrophoresis on various carriers and identified by subsequent specific staining. Starch, agar, agarose, and polyacrylamide gels, cellulose acetate foils, and dex-trans such as Sephadex are the most commonly used carrier media. Markert and Mpller (1959) were the first to apply the technique of starch gel electrophoresis in separating dehydrogenases. Apart from the fact that such electrophoreses are easily carried out, they require only... 

Fig. 81. Iliotograph of starch gel after electrophoresis of crystalline preparations of lactate dehydrogenase from bovine muscles (special reacticn for enzyme LDH-1, LDH-2, etc., isozyme fractions) (Markert and Appella, 1963).

A typical spectrum of individual lactate dehydrogenases (LDH) of muscles after electrophoresis on starch gel is shown in Fig. 81 (Markert and Appella, 1963). These five fractions, as mentioned previously, are determined by (he existence of two genetic loci for synthesis of two types of protein subunits, specific as regards amino acid composition and antigenicity, designated A and B, and by the presence of a tetramer structure of the principal protein (AAAA-LDH-5 AAAB-LDH-4 AABB-LDH-3 ABBB-LDH-2 BBBB-LDH-1). 

Fig. 83. Ontogenesis of lactate dehydrogenase isozymes of the mouse heart (starch gel electrophoresis). Numbers denote days before (-) and after (+) birth (Markert and Urs ung, 1962).

A. Amino Acid Analysis and Sequence. B. Immuno-diffusion. C. Density (iradient Sedimentation. D. Tritium-Labeling. E. Neutron Activation of Phosphorus. F. Histo-chemical Methods and Starch Gel Electrophoresis for Dehydrogenase Studies. G. Nuclear Magnetic Resonance and Electron Spin Resonance. H. Infra-red Measuremctits in Aqueous Media. I. Optical Rotatory Dispersion. 

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