【摘要】 以UW45抽提液的DEAE-纤维素柱层析的0.15M NaCl或0.25M NaCl洗出液与Smith法或Shah法制备的铁铝辅因子重组,则0.25 M NaCl洗出液的重组对乙炔还原的活性远较0.15 M NaGl的为高。0.15 M NaGl的洗出液较0.25 M NaCl洗出液的组分明显不纯。不全钼铁蛋白与铁钼辅因子和铁蛋白重组后能还原基质氰化钾,但对分子氮或迭氮化钠的还原却较微弱甚至不还原。铁钼辅因子按Smith和Shah法制备,其分子量范围分别为低于1000D和接近1500D。由于Smith和Shah法两种铁钼辅因子还原乙炔和氰化钾的比活不同,电泳图谱有差异、分子量又有大小,因此这两种铁钼辅因子的分子结构可能不尽相同。更多还原

【Abstract】 When 0.15 M NaCl or 0.95 M NaCl eluate of DEAE cellulose column chromatography of UW45 extract was reconstituted with FeMoCo prepared according to either Smith or Shah method, the C₂H₂-reduction activity of 0.25 M NaCl eluate recombination was much higher than that of 0.15 M NaCl eluate recombination, Polyacrylamide gel electrophoresis showed that the constitution of 0.15M NaCl eluate was apparently impure in comparison with that of 0.25 M NaCl eluate. After the inactive component Ⅰ was reconstituted with FeMoCo and Fe protein, it actually reduced KCN as substrate, while the reduction of N₂ or NaN₃ was rather weak even not at all. The molecular weight range of FeMoCo prepared according to Smith method was lower than 1000 daltons and that of Shah method was approximate to 1500 daltons. Owing to the difference in specific activities for C₂H₂ and KCN reductions, the discrepancy between electrophoretical profiles and the unequal of molecular weights of FeMoCo prepared according to different methods.these two kinds of FeMoCo are probable distinctive in the molecular structure.更多还原