Purification and characterization of zeta-crystallin/quinone oxidoreductasefrom camel liver

Zeta-Crystallin is a major protein in the lens of certain mammals. It hasbeen characterized as a novel NADPH: quinone oxidoreductases, showing limitedquinone substrate specificity. This study report for the first time purificationof this protein from camel liver by a sequential procedure of batch adsorptionchromatography using CM-Sephadex C-50, affinity chromatography using BlueSepharose CL-6B and 2þ, 5þ ADP-Sepharose 4B. The pure material was isolatedin a yield of 2.5% and purification fold of 253 over homogenate, with specificactivity of 22 units/mg protein. Kinetic and physical properties of this proteinhave been found to be identical with those of camel lens zeta-crystallin.