Regulation of the plasma membrane potential in Pneumocystis carinii.
Regulation of the plasma membrane potential in Pneumocystis carinii.
复制标题
卡氏肺囊虫质膜电位的调节。
DOI：
10.1111/j.1574-6968.2000.tb08979.x
复制
发表时间：
2000
影响因子：
2.1
通讯作者：
Docampo,R
中科院分区：
文献类型：
--
作者：
VanderHeyden,N;McLaughlin,GL;Docampo,R
许多原生生物利用跨质膜的H+梯度（质子动力）来驱动营养吸收。这种力部分由质膜电位（Δ ε）产生。我们用荧光染料双酚氧磷研究了卡氏肺孢子虫Δ λ的调节。在含有Na+和K+的缓冲液（标准缓冲液）中，稳态Δ V为−78±8 mV。在不存在Na+和K+（NMG缓冲液）或Cl−（葡萄糖酸盐缓冲液）的情况下，Δ λ没有显著变化，表明阳离子和阴离子电导在P中Δ λ的调节中不起显著作用。carinii。Na+/K+-ATP酶抑制剂哇巴因（1 mM）和K+/H+-ATP酶抑制剂奥美拉唑（1 mM）也不影响Δ λ。相比之下，质膜H+-ATP酶抑制剂二环己基碳二亚胺（100 μM）、N-乙基马来酰亚胺（100 μM）和己烯雌酚（25 μM）可显著地将Δ mV分别去极化至−43±7、−56±5和−40±12 mV。这些数据支持质膜H+-ATP酶在调节Δ CainP中起重要作用。carinii。
Many protists use a H+gradient across the plasma membrane, the proton motive force, to drive nutrient uptake. This force is generated in part by the plasma membrane potential (ΔΨ). We investigated the regulation of the ΔΨinPneumocystis cariniiusing the potentiometric fluorescent dye bisoxonol. The steady state ΔΨin a buffer containing Na+and K+(standard buffer) was found to be −78±8 mV. In the absence of Na+and K+(NMG buffer) or Cl−(gluconate buffer), ΔΨwas not significantly changed suggesting that cation and anion conductances do not play a significant role in the regulation of ΔΨinP. carinii. The ΔΨwas also not affected by inhibitors of the Na+/K+-ATPase, ouabain (1 mM), and the K+/H+-ATPase, omeprazole (1 mM). In contrast, inhibitors of the plasma membrane H+-ATPase, dicyclohexylcarbodiimide (100 μM),N-ethylmaleimide (100 μM) and diethylstilbestrol (25 μM), significantly depolarized the ΔΨto −43±7, −56±5 and −40±12 mV, respectively. The data support that the plasma membrane H+-ATPase plays a significant role in the regulation of ΔΨinP. carinii.