Rush J D, Maskos Z, Koppenol W H
Biodynamics Institute, Louisiana State University, Baton Rouge 70803-1800.
Arch Biochem Biophys. 1991 Aug 15;289(1):97-102. doi: 10.1016/0003-9861(91)90447-q.
A green manganese desferrioxamine complex is rapidly formed at room temperature upon stirring freshly precipitated manganese dioxide in a solution of the ligand. Spectral studies and low-temperature ESR indicate that this compound, which has been previously described as a manganese(III) complex, is better characterized as containing tetravalent manganese. The complex appears to form oligomers in solution. The extinction coefficient at 635 nm is 137 +/- 6 M-1 cm-1 (per manganese) at pH 7.8 and 88 +/- 4 M-1 s-1 at pH 6.6 after purification by chromatography. The superoxide dismutase activity was measured and compared to that of mononuclear manganese(III) 1,4,8,11-tetraazacyclodecane (cyclam). The catalytic rate constants for superoxide dismutase activity are 1.7 x 10(6) M-1 s-1 and 2.9 x 10(6) M-1 s-1 for the desferrioxamine and the cyclam complexes, respectively.
在室温下，将新沉淀的二氧化锰在配体溶液中搅拌，会迅速形成一种绿色的去铁胺锰络合物。光谱研究和低温电子顺磁共振表明，该化合物此前被描述为锰（III）络合物，但更准确的特征是含有四价锰。该络合物在溶液中似乎会形成低聚物。经色谱纯化后，在pH 7.8时，635 nm处的消光系数为137±6 M⁻¹ cm⁻¹（每锰），在pH 6.6时为88±4 M⁻¹ s⁻¹。测定了超氧化物歧化酶活性，并与单核锰（III）1,4,8,11-四氮杂环十四烷（环胺）的活性进行了比较。去铁胺络合物和环胺络合物的超氧化物歧化酶活性催化速率常数分别为1.7×10⁶ M⁻¹ s⁻¹和2.9×10⁶ M⁻¹ s⁻¹。
