Ali Nadia Ait, Dewez David, Didur Olivier, Popovic Radovan
Department of Chemistry, Environmental Toxicology Research Center, University of Quebec in Montreal, TOXEN, 2101, Jeanne-Mance, H2X 2J6, Montreal, Quebec, Canada.
Photosynth Res. 2006 Sep;89(2-3):81-7. doi: 10.1007/s11120-006-9085-5. Epub 2006 Sep 13.
The effect of chromium (Cr) on photosystem II (PSII) electron transport and the change of proteins content within PSII complex were investigated. When Lemna gibba was exposed to Cr during 96 h, growth inhibition was found to be associated with an alteration of the PSII electron transport at both PSII oxidizing and reducing sides. Investigation of fluorescence yields at transients K, J, I, and P suggested for Cr inhibitory effect to be located at the oxygen-evolving complex and Q(A) reduction. Those Cr-inhibitory effects were related to the change of the turnover of PSII D1 protein and the alteration of 24 and 33 kDa proteins of the oxygen-evolving complex. The inhibition of the PSII electron transport and the formation of reactive oxygen species induced by Cr were highly correlated with the decrease in the content of D1 protein and the amount of 24 and 33 kDa proteins. Therefore, functional alteration of PSII activity by Cr was closely related with the structural change within PSII complex.
研究了铬（Cr）对光系统II（PSII）电子传递的影响以及PSII复合物内蛋白质含量的变化。当浮萍在96小时内暴露于Cr时，发现生长抑制与PSII氧化侧和还原侧的PSII电子传递改变有关。对瞬态K、J、I和P处荧光产量的研究表明，Cr的抑制作用位于放氧复合体和Q(A)还原处。这些Cr抑制作用与PSII D1蛋白周转的变化以及放氧复合体24 kDa和33 kDa蛋白的改变有关。Cr诱导的PSII电子传递抑制和活性氧的形成与D1蛋白含量以及24 kDa和33 kDa蛋白量的减少高度相关。因此，Cr对PSII活性的功能改变与PSII复合物内的结构变化密切相关。
