Rao P V, Zigler J S
Laboratory of Mechanisms of Ocular Diseases National Eye Institute, National Institutes of Health, Bethesda, MD 20892.
Biochim Biophys Acta. 1992 Oct 27;1117(3):315-20.
zeta-Crystallin, a major lens protein of certain mammalian species, has recently been characterized as a novel and active NADPH:quinone oxidoreductase. Here we report the purification of this protein from guinea pig liver by utilizing sequentially: ammonium sulphate precipitation, Blue Sepharose affinity, cation exchange and hydrophobic chromatography steps. This four-step isolation procedure yielded 118-fold purification and a specific activity of 6 U/mg protein when assayed in the presence of 9,10-phenanthrenequinone. Kinetic, immunological and physical properties of this protein have been found to be identical with those of guinea pig lens zeta-crystallin. Western blot analysis using antibodies raised against zeta-crystallin peptides demonstrated the presence of substantial amounts of this protein in human liver homogenates.
