On the electrophoresis of cattle rhodopsin.

BRODA et al. studied frog rhodopsin in regard to the electrophoretic nature1). From the migration velocity of quartz particles on which frog rhodopsin and its bleached product had been adsorbed, they estimated the isoelectric points as being 4.47 and 4.57 respectively. Although a few available informations are suggestive of that the isoelectric point of cattle rhodopsin is rather on the less acidic side compared with that of frog rhodopsin, its exact value has not yet been reported2). For this reason, the present experiment was carried out by use of Tisselius Type Electrophoretic Apparatus in order to determine the isoelectric point of cattle rhodopsin and to discuss the nature of cattle rhodopsin as a protein-digitonin complex. My interest was also directed to inquire whether cattle rhodopsin and its bleached product can possibly be distinguished from each other on the electro-