Toxic effects of mercury on PSI and PSII activities, membrane potential and transthylakoid proton gradient in Microsorium pteropus
Toxic effects of mercury on PSI and PSII activities, membrane potential and transthylakoid proton gradient in Microsorium pteropus
复制标题
DOI：
10.1016/j.jphotobiol.2013.07.012
复制
发表时间：
2013-10-05
影响因子：
5.4
通讯作者：
Wang, Shuzhi
中科院分区：
文献类型：
--
作者：
Deng, Chunnuan;Zhang, Daoyong;Wang, Shuzhi
汞（Hg）是环境中最毒的金属之一，对生物体构成极大的风险。本研究旨在阐明Hg2+对光系统I（PSI）和光系统II（PSII）的能量转换、膜电位和质子梯度（一种水生植物）的毒性作用。测定了不同浓度Hg2+处理下的翼龙的叶绿素a、叶绿素b和类胡萝卜素的含量，以及PSI和PSII的量子产率和电子转移。随着Hg2+浓度的增加，PSI [Y(I)和ETR(I)]和PSII [Y(II)和ETR(II)]的量子产率和电子传输降低，而PSI [Y(ND)]供体侧的限制增加。当>= 165 mu g L-1 Hg2+时，PSII中非光致非光化学荧光猝灭[Y(NO)]的量子产率显着增加，但光致非光化学荧光猝灭[Y(NPQ)]的量子产率下降。与对照相比，330 μg L-1 Hg2+ 下翼龙的膜电位 (Delta psi) 和质子梯度 (Delta pH) 显着降低。汞暴露影响了翼龙 PSII 和 PSI 的多个位点。 (C) 2013 Elsevier B.V. 保留所有权利。
Mercury (Hg) is one of the top toxic metals in environment and it poses a great risk to organisms. This study aimed to elucidate the toxic effects of Hg2+ on energy conversion of photosystem I (PSI) and photosystem II (PSII), membrane potential and proton gradient of Microsorium pteropus (an aquatic plant species). Contents of chlorophyll a, chlorophyll b and carotenoids, quantum yield and electron transfer of PSI and PSII of M. pteropus exposed to various concentrations of Hg2+ were measured. With increasing Hg2+ concentration, quantum yield and electron transport of PSI [Y(I) and ETR(I)] and PSII [Y(II) and ETR(II)] decreased whereas limitation of donor side of PSI [Y(ND)] increased. At >= 165 mu g L-1 Hg2+, quantum yield of non-light-induced non-photochemical fluorescence quenching in PSII [Y(NO)] significantly increased but quantum yield of light-induced non-photochemical fluorescence quenching [Y(NPQ)] decreased. Membrane potential (Delta psi) and proton gradient (Delta pH) of M. pteropus were reduced significantly at 330 mu g L-1 Hg2+ compared to control. Mercury exposure affected multiple sites in PSII and PSI of M. pteropus. (C) 2013 Elsevier B.V. All rights reserved.