Shuvalov V A, Allakhverdiev S I, Sakamoto A, Malakhov M, Murata N
Department of Regulation Biology, National Institute for Basic Biology, Myodaiji, Okazaki, Japan.
IUBMB Life. 2001 Feb;51(2):93-7. doi: 10.1080/15216540118716.
The expression of the cytM gene, which encodes cytochrome cM in Synechocystis sp. PCC 6803, is induced under stress conditions such as low temperature. Results of spectrophotometric studies revealed that cytochrome cM was oxidized by light absorbed by photosystem I in cells that had acclimatized to a low temperature. However, no similar light-induced oxidation of cytochrome cM was observed in delta cytM mutant cells. The kinetics of the oxidation and reduction of P700 before and after acclimation of Synechocystis cells to low temperature suggested that cytochrome cM might donate electrons to photooxidized P700. Our observations indicate that cytochrome cM is synthesized under low-temperature stress and that it might carry electrons directly to P700+ in photosystem I.
在集胞藻PCC 6803中编码细胞色素cM的cytM基因的表达在诸如低温等应激条件下被诱导。分光光度研究结果表明，在适应低温的细胞中，细胞色素cM被光系统I吸收的光氧化。然而，在缺失cytM的突变体细胞中未观察到类似的细胞色素cM光诱导氧化。集胞藻细胞适应低温前后P700氧化和还原的动力学表明，细胞色素cM可能将电子传递给光氧化的P700。我们的观察结果表明，细胞色素cM在低温胁迫下合成，并且它可能将电子直接传递给光系统I中的P700+。
