Researches on photo-utilization of Zn-bacteriochlorophyll-containing phototrophic bacteria

长期以来，人们一直认为Mg-（细菌）叶绿素是自然界光合作用所必需的。然而，新的光合色素，含锌细菌叶绿素（Zn-BCh 1）被发现存在于嗜酸性好氧异养细菌，嗜酸菌属，并在细胞中的生理功能。本文以红色嗜酸菌（Acidiphilium rubrum）为模式菌株，研究了光照条件下光合作用的光能转化为电能（电流产生）、化学能（ATP）和还原力（NADPH）的产生以及CO_2的固定，并研究了在不同条件下添加介体（HNQ）的电化学电池的电流输出。结果，可以在新鲜细菌细胞中检测到光诱导电流输出。ATP和NADPH的产生与光照强度有关。利用<14>完整细胞和细胞膜组分的CO_2分析表明，在有氧和光照条件下，CO_2固定。

It has been thought for a long time that Mg-(bacterio) chlorophylls are essential for the photosynthesis in nature. However, the new photosynthetic pigment, Zn-containing bacteriochlorophyll (Zn-BCh1) was discovered to be present in the acidophilic aerobic heterotrophic bacteria, Acidiphilium sp, and to be physiologically functional in cells. The present researches were made, using Acidiphilium rubrum as the type strain, on the conversion of light energy into electrical energy (current generation) via photosynthesis, the productions of chemical energy (ATP) and reducing power (NADPH), and CO_2 fixation under illumination.The current outputs using electrochemical cells added with the mediator (HNQ) under illumination were investigated under various conditions. As a result photo-induced current outputs could be detected in fresh bacterial cells. The productions of ATP and NADPH were dependent on the light intensity. The ^<14>CO_2 analyses using both intact cells and cell membrane fractions revealed the fixation of CO_2 under aerobic and light conditions.