Nikandrov V V, Brin G P, Krasnovskií A A
Mol Biol (Mosk). 1978 Nov-Dec;12(6):1278-87.
The condition of methylviologen photoreduction by chloroplasts was investigated. Argon bubbling through the suspension of chloroplasts or degasing in vacuum caused inhibition of methylviologen reduction probably due to the denaturation of chloroplast membranes at the water/air boundary. Adding glycerol or bovine serum albumine or removing oxygen from chloroplast suspension with the aid of the oxygen absorbing-systems preserved the activity of chloroplasts. Methylviologen photoreduction is inhibited by DCMU (10(-7) M) and Tris-buffer treatment and is activated by uncouples. The pH-dependence is similar to that of the Hill reaction. Triton X-100 (0.007%), ethyl ether (2%) and heating up to 42 degrees activated the Hill reaction but inhibited methylviologen reduction. Water molecule probably acts as an initial electron donor in this reaction. It is proposed that the steady level of methylviologen photoreduction is determined by a relationship between the rate of methylviologen electron acceptance and cyclic electron flow short-circuiting photosystem I.
对叶绿体介导的甲基紫精光还原条件进行了研究。向叶绿体悬浮液中鼓入氩气或在真空中脱气会抑制甲基紫精的还原，这可能是由于叶绿体膜在水/气界面处发生了变性。添加甘油或牛血清白蛋白，或借助吸氧系统从叶绿体悬浮液中去除氧气，可保持叶绿体的活性。甲基紫精光还原受到二氯苯基二甲基脲（10⁻⁷ M）和Tris缓冲液处理的抑制，并被解偶联剂激活。pH依赖性与希尔反应相似。Triton X-100（0.007%）、乙醚（2%）以及加热至42摄氏度会激活希尔反应，但会抑制甲基紫精的还原。在该反应中，水分子可能作为初始电子供体。有人提出，甲基紫精光还原的稳定水平由甲基紫精电子接受速率与绕过光系统I的循环电子流之间的关系决定。
