Yamashoji Shiro, Al Mamun Arafat, Bari Latiful
Microbial Technology Laboratory, 9-50-514 Kaigandori, Tarumi-ku, Kobe City, Hyogo, 655-0036, Japan.
Center for Advanced Research in Sciences, University of Dhaka, Dhaka, 1000, Bangladesh.
Biochem Biophys Rep. 2020 Oct 5;24:100823. doi: 10.1016/j.bbrep.2020.100823. eCollection 2020 Dec.
Cytotoxic effects of menadione on normal and cytochrome c-deficient yeast cells were examined on the basis of the cell growth rate, NAD(P)H concentration, reactive oxygen production, plasma membrane H-ATPase activity, and ethanol production. In aerobically or anaerobically cultured yeast cells, NAD(P)H concentration decreased with increasing concentration of menadione, and the recovery of NAD(P)H concentration was proportional to the cell growth rate. However, there was no relationship among the inhibition of the cell growth and reactive oxygen production, plasma membrane H-ATPase activity, and ethanol production. Among them, ethanol production showed resistance to the cytotoxicity of menadione, suggesting the resistance of glycolysis to menadione. The growth inhibitory effect of menadione depended on the rapid decrease and the recovery of NAD(P)H rather than production of reactive oxygen species regardless of aerobic culture or anaerobic culture and presence or absence of mitochondrial function. The recovery of NAD(P)H concentration after the addition of menadione might depend on menadione-resistant glycolytic enzymes.
基于细胞生长速率、NAD(P)H浓度、活性氧生成、质膜H-ATP酶活性和乙醇生成，研究了甲萘醌对正常酵母细胞和细胞色素c缺陷型酵母细胞的细胞毒性作用。在需氧或厌氧培养的酵母细胞中，NAD(P)H浓度随甲萘醌浓度的增加而降低，且NAD(P)H浓度的恢复与细胞生长速率成正比。然而，细胞生长抑制与活性氧生成、质膜H-ATP酶活性和乙醇生成之间没有关系。其中，乙醇生成对甲萘醌的细胞毒性具有抗性，表明糖酵解对甲萘醌具有抗性。无论需氧培养还是厌氧培养，以及线粒体功能是否存在，甲萘醌的生长抑制作用取决于NAD(P)H的快速降低和恢复，而不是活性氧的产生。添加甲萘醌后NAD(P)H浓度的恢复可能取决于对甲萘醌具有抗性的糖酵解酶。
