tailieunhanh - Báo cáo khoa học: Preliminary molecular characterization and crystallization of mitochondrial respiratory complex II from porcine heart

The mitochondrial respiratory complex II, or succinate:ubiquinone oxido-reductase, is an integral membrane protein complex in both the tricarboxy-lic acid cycle (Krebs cycle) and aerobic respiration. The gene sequences of each complex II subunit were measured by RT-PCR. N-terminal sequen-cing work was performed to identify the mitochondrial targeting signal peptide of each subunit. | ễFEBS Journal Preliminary molecular characterization and crystallization of mitochondrial respiratory complex II from porcine heart Xia Huo1 2 Dan Su1 Aojin Wang2 Yujia Zhai2 Jianxing Xu2 Xuemei Li2 Mark Bartlam1 2 Fei Sun2 and Zihe Rao1 2 1 Tsinghua-Nankai-IBP Joint Research Group for StructuralBiology Tsinghua University Beijing China 2 NationalLaboratory of Biomacromolecules Institute of Biophysics IBP Chinese Academy of Sciences Beijing China Keywords complex II crystallization membrane protein mitochondrial respiration sequencing Correspondence M. Bartlam Laboratory of Structural Biology Life Sciences Building Tsinghua University Beijing 100084 China Fax 86 10 62773145 Tel 86 10 62771493 E-mail bartlam@ F. Sun Laboratory of Biological Electron Microscopy and Structural Biology Institute of Biophysics Chinese Academy of Sciences 15 Datun Road Chaoyang District Beijing 100101 China Fax Tel 86 10 64888582 E-mail feisun@ The mitochondrial respiratory complex II or succinate ubiquinone oxido-reductase is an integral membrane protein complex in both the tricarboxylic acid cycle Krebs cycle and aerobic respiration. The gene sequences of each complex II subunit were measured by RT-PCR. N-terminal sequencing work was performed to identify the mitochondrial targeting signal peptide of each subunit. Complex II was extracted from porcine heart and purified by the ammonium sulfate precipitation method. The sample was solubilized by w v sugar detergent n-decyl-P-D-maltoside stabilized by 200 mM sucrose and crystallized with 5 w v poly ethylene glycol 4000. Important factors for the extraction purification and crystallization of mitochondrial respiratory complex II are discussed. Received 10 November 2006 revised 18 December 2006 accepted 15 January 2007 doi Mitochondria are cellular organelles of prokaryotic origin that are found in almost all eukaryotic cells. The mitochondrial respiratory system consisting