Properties of a transplasma membrane electron transport system in HeLa cells
Properties of a transplasma membrane electron transport system in HeLa cells
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HeLa 细胞跨质膜电子传递系统的特性
DOI：
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发表时间：
1984
影响因子：
3
通讯作者：
H. Löw
中科院分区：
文献类型：
--
作者：
I. Sun;F. L. Crane;C. Grebing;H. Löw
利用外部不渗透氧化剂铁氰化物，研究了HeLa细胞中的跨膜电子传递系统。HeLa细胞对铁氰化物的还原表现为两相动力学，快速阶段的速率可达500 nmol /min/g w.w.（湿重），慢阶段的速率为该速率的一半。明显的km在高速时是0.125 mM，在低速时是0.24 mM。还原速率与细胞浓度成正比。糖酵解抑制剂对速率的抑制表明还原依赖于糖酵解，这有助于细胞质电子供体NADH。铁氰化物的还原被证明发生在细胞外部，因为它受到外部pH值和与外表面反应的试剂的影响。铁氰化物的还原伴随着细胞中质子的释放。每还原1摩尔铁氰化物，释放2.3摩尔质子。因此，可以得出结论，HeLa细胞中的跨膜氧化还原系统与跨膜的质子梯度产生耦合。我们认为这种氧化还原系统可能是控制HeLa细胞膜功能的能量来源。铁氰化物（0.33-0.1 mM）对细胞生长的促进作用，可以部分替代血清作为生长因子，有力地支持了这一假设。
A transmembrane electron transport system has been studied in HeLa cells using an external impermeable oxidant, ferricyanide. Reduction of ferricyanide by HeLa cells shows biphasic kinetics with a rate up to 500 nmoles/min/g w.w. (wet weight) for the fast phase and half of this rate for the slow phase. The apparentKm is 0.125 mM for the fast rate and 0.24 mM for the slow rate. The rate of reduction is proportional to cell concentration. Inhibition of the rate by glycolysis inhibitors indicates the reduction is dependent on glycolysis, which contributes the cytoplasmic electron donor NADH. Ferricyanide reduction is shown to take place on the outside of cells for it is affected by external pH and agents which react with the external surface. Ferricyanide reduction is accompanied by proton release from the cells. For each mole of ferricyanide reduced, 2.3 moles of protons are released. It is, therefore, concluded that a transmembrane redox system in HeLa cells is coupled to proton gradient generation across the membrane. We propose that this redox system may be an energy source for control of membrane function in HeLa cells. The promotion of cell growth by ferricyanide (0.33–0.1 mM), which can partially replace serum as a growth factor, strongly supports this hypothesis.
大鼠肝脏跨质膜氧化还原系统的特性和调节。
DOI：
10.1042/bj2040795
发表时间：
1982
期刊：
The Biochemical journal
影响因子：
--
作者：
Clark,MG;Partick,EJ;Crane,FL
通讯作者：
Crane,FL
大鼠肝脏细胞外铁氰化物还原的证据。
DOI：
10.1042/bj2000565
发表时间：
1981
期刊：
The Biochemical journal
影响因子：
--
作者：
Clark,MG;Partick,EJ;Patten,GS;Crane,FL;Löw,H;Grebing,C
通讯作者：
Grebing,C