Departamento de Genética Molecular, Instituto de Fisiología Celular, Universidad Nacional Autónoma de México, Mexico; Genetics and Physiology of microalgae, InBioS/Phytosystems, University of Liège, Belgium.
Departamento de Genética Molecular, Instituto de Fisiología Celular, Universidad Nacional Autónoma de México, Mexico.
Biochim Biophys Acta Bioenerg. 2018 Jun;1859(6):434-444. doi: 10.1016/j.bbabio.2018.03.004. Epub 2018 Mar 11.
The proposal that the respiratory complexes can associate with each other in larger structures named supercomplexes (SC) is generally accepted. In the last decades most of the data about this association came from studies in yeasts, mammals and plants, and information is scarce in other lineages. Here we studied the supramolecular association of the FF-ATP synthase (complex V) and the respiratory complexes I, III and IV of the colorless alga Polytomella sp. with an approach that involves solubilization using mild detergents, n-dodecyl-β-D-maltoside (DDM) or digitonin, followed by separation of native protein complexes by electrophoresis (BN-PAGE), after which we identified oligomeric forms of complex V (mainly V and V) and different respiratory supercomplexes (I/IV, I/III, I/IV). In addition, purification/reconstitution of the supercomplexes by anion exchange chromatography was also performed. The data show that these complexes have the ability to strongly associate with each other and form DDM-stable macromolecular structures. The stable V ATPase oligomer was observed by electron-microscopy and the association of the respiratory complexes in the so-called "respirasome" was able to perform in-vitro oxygen consumption.
该提议认为，呼吸复合物可以在更大的结构中相互关联，这些结构被命名为超级复合物（SC）。在过去的几十年中，大多数关于这种关联的信息都来自酵母、哺乳动物和植物的研究，而在其他谱系中信息则相对较少。在这里，我们研究了无色藻类 Polytomella sp. 的 FF-ATP 合酶（复合物 V）与呼吸复合物 I、III 和 IV 的超分子关联，方法是使用温和的去污剂（DDM 或十二烷基-β-D-麦芽糖苷）或去氧胆酸钠进行溶解，然后通过电泳（BN-PAGE）分离天然蛋白复合物，之后我们鉴定了复合物 V 的聚合形式（主要是 V 和 V）和不同的呼吸超级复合物（I/IV、I/III、I/IV）。此外，还通过阴离子交换色谱法对超级复合物进行了纯化/重组。数据表明，这些复合物具有强烈相互关联并形成 DDM 稳定的大分子结构的能力。通过电子显微镜观察到稳定的 V ATPase 寡聚物，并且呼吸复合物在所谓的“respirasome”中的关联能够进行体外耗氧。
