Nardilysin facilitates complex formation between mitochondrial malate dehydrogenase and citrate synthase.
Nardilysin facilitates complex formation between mitochondrial malate dehydrogenase and citrate synthase.
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DOI：
10.1016/j.bbagen.2005.02.010
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发表时间：
2005-05
期刊：
影响因子：
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通讯作者：
K. Chow;Zhangliang Ma;Jian Cai;W. Pierce;L. Hersh
中科院分区：
文献类型：
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作者：
K. Chow;Zhangliang Ma;Jian Cai;W. Pierce;L. Hersh
凝胶过滤色谱显示，大鼠睾丸或大鼠脑提取物中的nardilysin活性表现出的表观分子量为10300 kDa，相比之下，纯化的酶的表观分子量为187 kDa。将纯化的nardilysin加入到大鼠脑提取物中，但不加入到E.大肠杆菌提取物，产生的高分子物种。添加含有纳地赖氨酸酸性结构域的GST融合蛋白消除了较高分子量的纳地赖氨酸形式，表明寡聚化涉及纳地赖氨酸的酸性结构域。用固定化的nardilysin柱，线粒体苹果酸脱氢酶（mMDH）和柠檬酸合酶（CS）的分离，从一个分级的大鼠脑提取物。猪mMDH，而不是猪胞质MDH，显示与那地赖氨酸形成异二聚体。线粒体MDH增加nardilysin活性约50%，而nardilysin稳定mMDH对热失活。CS与mMDH的共免疫沉淀只有在存在的nardilysin表明，nardilysin促进复合物的形成。
Gel filtration chromatography showed that nardilysin activity in a rat testis or rat brain extract exhibited an apparent molecular weight of ∼300 kDa compared to ∼187 kDa for the purified enzyme. The addition of purified nardilysin to a rat brain extract, but not to an E. coli extract, produced the higher molecular species. The addition of a GST fusion protein containing the acidic domain of nardilysin eliminated the higher molecular weight nardilysin forms, suggesting that oligomerization involves the acidic domain of nardilysin. Using an immobilized nardilysin column, mitochondrial malate dehydrogenase (mMDH) and citrate synthase (CS) were isolated from a fractionated rat brain extract. Porcine mMDH, but not porcine cytosolic MDH, was shown to form a heterodimer with nardilysin. Mitochondrial MDH increased nardilysin activity about 50%, while nardilysin stabilized mMDH towards heat inactivation. CS was co-immunoprecipitated with mMDH only in the presence of nardilysin showing that nardilysin facilitates complex formation.