کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
6308415 1618854 2014 6 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Changes in the physiology and gene expression of Microcystis aeruginosa under EGCG stress
موضوعات مرتبط
علوم زیستی و بیوفناوری علوم محیط زیست شیمی زیست محیطی
پیش نمایش صفحه اول مقاله
Changes in the physiology and gene expression of Microcystis aeruginosa under EGCG stress
چکیده انگلیسی
EGCG (Epigallocatechin-3-gallate) has an allelopathic inhibitory effect on Microcystis aeruginosa. Cellular structure, physiological and biochemical reactions and gene expression were examined to explore the mechanism of inhibition. As was shown in electron microscopy, the structure of the cell wall, cell membrane and thylakoid was disrupted by EGCG. EGCG also reduced the efficiency of photosynthesis and the electron transfer rate in M. aeruginosa cells, as was determined with a flow cytometer. Quantitative real-time PCR analysis demonstrated that gene expression of the core proteins of the photosynthesis centers PSI and PSII and ATP synthase were reduced, while the expression of the phycobilisome degradation protein A gene (nbl A) was elevated. The expression of the universal stress protein gene increased, which would enhance the adaptive capacity of Microcystis cells to polyphenols and oxidative stress. Furthermore, EGCG elevated the level of reactive oxygen species (ROS) in M. aeruginosa cells, and thus caused oxidative cellular damage. When treated with EGCG at low concentrations (10 and 40 mg L−1), the cells were able to activate defense systems to degrade the excess ROS. But at a concentration of 70 mg L−1, oxidative stress exceeded tolerance limits, and the cells were severely damaged. We concluded that damage to photosynthesis and oxidative stress were the primary mechanisms for the allelopathic effect of EGCG on M. aeruginosa.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Chemosphere - Volume 117, December 2014, Pages 164-169
نویسندگان
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