A superoxide dismutase(SOD) was purified to homogeneity from fresh camellia pollen by means of ammonium sulfate precipitation and column chromatography with DEAE-cellulose(DE52), Sephadex G-100 and phenyl sepharose^TM 6 Fast Flow columns. Its specific activity could reach to 4034 U/mg protein and it was determined to be Cu/Zn-SOD according to its different sensitivities to different inhibitors. The molecular weight of the SOD and its subunit were 69500 and 34700, respectively, based on sodium dodecyl sulfate-polyacrylamide gel electrophoresis(SDS-PAGE), which implicates that the SOD in camellia pollen is a dimmer composed of two identical subunits. The iso-electric point of the enzyme was determined to be 4.1 by isoelectric focusing electrophoresis and the N-terminal amino acid was identified to be Gly by the DNS-Cl method. Its α-Helix was also calculated to be approximately 21.8% according to the circular dichroism(CD) spectra.
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