摘要
棕色固氮菌固氮酶铁铝蛋白与邻菲啰啉混合后,生成一种红色的亚铁-邻菲啰啉螯合物。处理蛋白的Mo含量几乎不变,但Fe/Mo比降低;处理蛋白的乙炔还原活性、克分子消光系数ε_(700nm)和圆二色性克分子消光系数Δε_(450nm)随着失去的Fe原子数目的增加而几乎成比例降低;失去的活性可为轻度氧钝化的铁钼蛋白恢复。结果表明,邻菲啰啉可能通过专一螯合P-cluster中的Fe原子而使其结构受到破坏,从而使铁钼蛋白失去活性。由此可推论出,P-cluster在铁钼蛋白还原底物过程中起着重要的作用。
A red chelate compound of ferrous ophenanthroline appeared after o-phenanthroline was added to the solution of crystalline FeMo protein. The Mo content of the treated FeMo protein was almost not decreased, but the ratio of Fe to Mo atoms in the protein decreased; C_2H_2-reduction activity, molecular extinction coefficient ε_(700nm) and molecnlar circular dichroic extinction coefficient △ε_(450nm) of the treated protein were almost proportionally decreased when the lost Fe atoms in increased. And the activity was able to be restored by an addition of an aerated FeMo protein which was not severely damaged. The results show that a loss of activity of the treated protein is due to a removal of Fe atom by o-phenanthroline, which results in destructure of P-clusters. Therefore, it seems to be reasonable to deduce that P-clusters in FeMo protein can play an important role in the reduction of substrates.
出处
《微生物学报》
CAS
CSCD
北大核心
1989年第1期51-57,共7页
Acta Microbiologica Sinica
关键词
棕色固氮菌
铁钼蛋白
邻菲罗啉
o-phenanthroline
Function of P-cluster: FeMo protein
Azotobacter vinelandii
