Different Resistance to UV-B Radiation of Extracellular Polymeric Substances of Two Cyanobacteria from Contrasting Habitats.
Different Resistance to UV-B Radiation of Extracellular Polymeric Substances of Two Cyanobacteria from Contrasting Habitats.
复制标题
对比生境的两种蓝藻胞外聚合物对 UV-B 辐射的不同抵抗力
DOI：
10.3389/fmicb.2016.01208
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发表时间：
2016
影响因子：
5.2
通讯作者：
Pan X
中科院分区：
文献类型：
--
作者：
Song W;Zhao C;Zhang D;Mu S;Pan X
研究了UV-B辐射（UVBR）对水生集胞藻（Synechocystis sp.）和沙漠微小色球藻（Chroococcus minutus）光合活性（Fv/Fm）的影响，以及对集胞藻（Synechocystis sp.）和微小色球藻（Chroococcus minutus）胞外聚合物（EPS）组成和荧光性质的影响。minutus进行了比较研究。沙漠蓝藻C.微小集胞藻PSII活性（Fv/Fm）对UVBR的耐受性高于水生集胞藻，以及抑制的C.对微小集胞藻（Synechocystis sp.）的影响可完全恢复，而对集胞藻（Synechocystis sp.）的影响可部分恢复。UVBR对两种植物的产量和EPS的生化组成有显著影响。在集胞藻EPS中检测到类蛋白质和类胡敏酸物质，在C. minutus。UVBR对荒漠植物和水生植物EPS中蛋白质的降解作用显著，且后者更易被降解。两种植物的多糖比蛋白质更能抵抗UVBR。集胞藻多糖降解程度较轻，而C. minutus几乎没有分解。沙漠蓝细菌对UVBR的耐受性较水生蓝细菌高，这可能是由于其胞外多糖对UVBR诱导的光降解具有较强的抗性。
The effects of UV-B radiation (UVBR) on photosynthetic activity (Fv/Fm) of aquatic Synechocystis sp. and desert Chroococcus minutus and effects on composition and fluorescence property of extracellular polymeric substances (EPSs) from Synechocystis sp. and C. minutus were comparatively investigated. The desert cyanobacterium species C. minutus showed higher tolerance of PSII activity (Fv/Fm) to UVBR than the aquatic Synechocystis sp., and the inhibited PSII activity of C. minutus could be fully recovered while that of Synechocystis sp. could be partly recovered. UVBR had significant effect on the yield and biochemical composition of EPS of both species. Protein-like and humic acid-like substances were detected in EPS from Synechocystis sp., and protein-like and phenol-like fluorescent compounds were detected in EPS from C. minutus. Proteins in EPS of desert and aquatic species were significantly decomposed under UVBR, and the latter was more easily decomposed. The polysaccharides were much more resistant to UVBR than the proteins for both species. Polysaccharides of Synechocystis sp. was degraded slightly but those of C. minutus was little decomposed. The higher tolerance to UVBR of the desert cyanobacterium can be attributed to the higher resistance of its EPS to photodegradation induced by UVBR in comparison with the aquatic species.