Rotenone‐insensitive internal NADH‐quinone oxidoreductase of Saccharomyces cerevisiae mitochondria: the enzyme expressed in Escherichia coli acts as a member of the respiratory chain in the host cells

FEBS Letters

Yagi, Takao¹  Kitajima-Ihara, Tomomi¹ 

[1] Division of Biochemistry, Department of Molecular and Experimental Medicine, The Scripps Research Institute, La Jolla, CA 92037, USA

关键词: NADH-quinone oxidoreductase;    Expression;    Saccharomyces cerevisiae;    Escherichia coli;    Mitochondrion;    Q;    quinone;    UQ1;    ubiquinone-1;    NDH-1;    bacterial proton-translocating NADH-quinone oxidoreductase(s);    complex I;    mitochondrial proton-translocating NADH-quinone oxidoreductase(s);    NDI1;    internal rotenone-insensitive NADH-Q oxidoreductase in mitochondria;    NDH-2;    bacterial NADH-Q oxidoreductase lacking the energy-coupling site;    SDS;    sodium dodecylsulfate;    IPTG;    isopropyl-β-d-thiogalactopyranoside;    deamino-NADH;    reduced nicotinamide hypoxanthine dinucleotide;    DCCD;    N;    N′-dicyclohexylcarbodiimide;    SMP;    submitochondrial particles (inside-out membranes);    T7 tag-fused mature NDI1;    mature NDI1 fused by T7 tag sequence MASMTGGQQMGRG at the N-terminus;   

DOI  :  10.1016/S0014-5793(97)01533-0

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

The NDI1 gene encodes the internal rotenone-insensitive NADH-quinone oxidoreductase localized in the inner mitochondrial membranes of Saccharomyces cerevisiae. The T7 tag-fused mature NDI1 was overexpressed in Escherichia coli. The overexpressed NDI1 was exclusively found in the membrane fraction. The NDI1-overexpressed membranes showed significantly increased activities of NADH oxidase and NADH-ubiquinone-1 (UQ₁) reductase when compared with the control membranes. Flavone, which is a specific inhibitor of the S. cerevisiae NDI1, inhibited almost completely NADH oxidase and NADH-UQ₁ reductase activities of NDI1-overexpressed membranes but scarcely inhibited these activities of the control membranes. In addition, the NADH oxidase activity of the NDI1-overexpressed membranes was also inhibited by KCN as well as the control membranes. These results indicate that the overexpressed NDI1 worked as a member of the respiratory chain in the host cells, even though E. coli membranes are different from S. cerevisiae inner mitochondrial membranes in terms of quinones and lipid composition.

【 授权许可】

Unknown