Ultraviolet radiation stimulated activity of extracellular carbonic anhydrase in the marine diatom Skeletonema costatum.
Ultraviolet radiation stimulated activity of extracellular carbonic anhydrase in the marine diatom Skeletonema costatum.
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紫外线辐射刺激海洋硅藻中肋骨条细胞外碳酸酐酶的活性。
DOI：
10.1071/fp08172
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发表时间：
2009-02
期刊：
影响因子：
--
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中科院分区：
文献类型：
--
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先前的研究表明，减少太阳紫外线辐射（280-400 nm）可以增强海洋浮游植物的光合固碳作用，但其机制尚不清楚。在大多数海洋浮游植物物种中，细胞外（周质）碳酸酐酶（CAe）促进了光合作用所需的CO2供应。本研究表明，在可见光照射的基础上，用UV-A（320-395 nm）或UV-A + UV-B（295-320 nm）处理中肋骨条藻，可刺激其CAe活性。暴露1小时后，UV-A和UV-B的存在在低辐照度（PAR 161，UV-A 28，UV-B 0.9 W m−2）下分别使活性增强了28%和24%，在高辐照度（PAR 328，UV-A 58，UV-B 1.9 W m−2）下分别增强了21%和19%。紫外线辐射刺激CAe活性贡献高达6%的光合固碳的结果，增强供应的CO2，揭示使用CAe抑制剂（乙酰唑胺）。结果表明，与PSII的表观量子产率相比，光合碳固定的抑制作用较小。在UV-A和/或UV-B的存在下，UV辐射刺激的CAe活性与质膜上氧化还原活性的增强相一致。本研究表明，紫外辐射能增强CAe活性，这在抵消紫外线对光合作用的抑制中起着重要作用。
Previous studies have shown that reduced levels of solar UV radiation (280–400 nm) can enhance photosynthetic carbon fixation of marine phytoplankton, but the mechanisms are not known. The supply of CO2 for photosynthesis is facilitated by extracellular (periplasmic) carbonic anhydrase (CAe) in most marine phytoplankton species. The present study showed that the CAe activity of Skeletonema costatum (Greville) Cleve was stimulated when treated with UV-A (320–395 nm) or UV-A + UV-B (295–320 nm) in addition to visible radiation. The presence of UV-A and UV-B enhanced the activity by 28% and 24%, respectively, at a low irradiance (PAR 161, UV-A 28, UV-B 0.9 W m−2) and by 21% and 19%, respectively, at a high irradiance (PAR 328, UV-A 58, UV-B 1.9 W m−2) level after exposure for 1 h. Ultraviolet radiation stimulated CAe activity contributed up to 6% of the photosynthetic carbon fixation as a result of the enhanced supply of CO2, as revealed using the CAe inhibitor (acetazolamide). As a result, there was less inhibition of photosynthetic carbon fixation compared with the apparent quantum yield of PSII. The UV radiation stimulated CAe activity coincided with the enhanced redox activity at the plasma membrane in the presence of UV-A and/or UV-B. The present study showed that UV radiation can enhance CAe activity, which plays an important role in counteracting UV inhibition of photosynthesis.
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影响因子：
7.4
作者：
Nimer, NA;Brownlee, C;Merrett, MJ
通讯作者：
Merrett, MJ
DOI：
10.1007/978-94-007-1038-2_11
发表时间：
2003
期刊：
--
影响因子：
--
作者：
J. Raven;J. Beardall
通讯作者：
J. Raven;J. Beardall
影响因子：
--
作者：
J. Raven
通讯作者：
J. Raven
影响因子：
2.9
作者：
L. Franklin
通讯作者：
L. Franklin
影响因子：
2.1
作者：
K. Aizawa;S. Miyachi
通讯作者：
K. Aizawa;S. Miyachi