Arrhenius parameters of phototransients in Halobacterium halobium in physiological conditions
Arrhenius parameters of phototransients in Halobacterium halobium in physiological conditions
复制标题
生理条件下盐杆菌光瞬变的阿伦尼乌斯参数
作者：
W. V. Sherman;S. Caplan
盐杆菌是暴露在明亮阳光下的温暖盐水池的原生细菌。这种细菌的菌株在细胞膜（“紫膜”）中合成一种紫色色素。一种叫做细菌视紫红质的蛋白质产生了这种特殊的颜色，在可见光谱中具有宽波段，最大波长为570nm（参考文献1-3）。色素细胞利用细菌视紫红质吸收的太阳辐射产生跨膜质子梯度，作为ATP合成的能量来源4,5。关于这种光驱动质子泵的工作机制的大部分信息是从紫色膜碎片悬浮液的分光光度法研究中获得的。我们在此报告了在该实验室开始的研究的延续，使用调制激发法11和传统闪光光度法12,13，其中我们使用后者技术来观察完整细胞的水悬浮液在生理温度和盐度（基础盐溶液）下的瞬态光谱变化。
Halobacterium halobium is indigenous to warm saline pools exposed to bright sunlight. Strains of this bacterium synthesise a purple pigment in the cell membrane (the ‘purple membrane’). A single protein, bacteriorhodopsin, is responsible for this characteristic colour, possessing a broad band in the visible spectrum with a maximum at 570 nm (refs 1–3). Pigmented cells utilise solar radiation absorbed by bacteriorhodopsin to create a transmembrane proton gradient which serves as an energy source for ATP synthesis4,5. Most information about the mechanism of operation of this light-driven proton pump has been obtained from spectrophotometric studies of suspensions of purple membrane fragments6–10. We report here a continuation of studies initiated in this laboratory using modulation excitation11 and conventional flash photometry12,13, in which we use the latter technique to observe transient spectral changes in aqueous suspensions of intact cells at physiological temperatures and salinity (basal salt solution).