Pepsin electrophoretic mobility

The presence of Al cause the decrease of pepsin electrophoretic mobility at all investigated concentrations. The degree of decrease is proportional to A13+ concentrations, which the one has been exposed. In the absence of Al ion, the electrophoretic mobility of pepsin under the physiological conditions the obtained Rs value for pepsin is 0.47 while in the presence of 1, 5 and 10 mM Al ions the obtained Rs values were 0.46, 0.44 and 0.42, respectively. 

These materials also differed in electrophoretic mobility at pH 5.0 in acetate buffer. The first peak (pepsin) in buffer of pH 5.0 moved 9 cm... 

Pugh et al. (P7) and Mack et al. (Mia, M2), using free boundary electrophoresis, showed that mucoprotein and mucoproteose fractions of the dissolved mucin (G5) had different electrophoretic mobilities mucoprotein fast anodic mobility (5.5-6.9 X cm sec volts ), mucoproteose slow anodic mobility (0.5-1.0 X cm sec volts ) in veronal buffer of pH 9.2 (Fig. 1). Soluble mucus had intermediate mobility of — 3.5 X 10 . It was also noted by Mack et al. (Ml) that the mucoprotein fraction processed from the acid human gastric juice, when nm by itself on Tiselius electrophoresis or when added to acid gastric juice, did not have as fast mobility as the fastest anodic component of the gastric juice, which had a mobility of 7.4-7.S X cm sec volts and which probably, as we know now, corresponded to the complex of pepsin and mucoprotein (see G5). 

Native electrophoresis of pepsin and hemoglobin on 10% polyacrylamide gel carried out at 48 °C during 90 min, according to the Laemmli procedure, at pH 8.3 (Laemly 1970). Water solutions of all samples of enzyme (pepsin dissolved in water to final concentration of 2 mg/mL) were titrated with HCl to pH 2 and incubated at 37 °C, with addition of different concentrations of Al + ion (1, 5 and 10 mM). The samples were diluted with sample buffer in ratio 1 1 (v/ v) and applied on gel in volume of 20 pL. Visualization was performed with Commassie Brilliant Blue G-250 dye. The gels scanned and processed using Corel Draw 11.0 software package. Quantification of electrophoretic mobility of the molecule is carried out via Rs value, where it is defined by ... 

Fig. 6. A - Native PAGE electrophoregram of pepsin without AP+ ions at pH 2. B -Visualization of quantified electrophoretic mobility of pepsin molecule treated at different temperatures.

Further evidence for the occurrence of a diester linkage in this protein is reflected in the electrophoretic behavior. Pepsin still moves anodically in 0.1 N hydrochloric acid, pH 1.08. On the other hand, the phosphorus-free pepsin is positively charged at this pH. It has an isoelectric pH of 1.7. As shown in Fig. 6, the mobilities of these two proteins differ by a... 

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