Contrasting Mixotrophic Lifestyles Reveal Different Ecological Niches in Two Closely Related Marine Protists
Contrasting Mixotrophic Lifestyles Reveal Different Ecological Niches in Two Closely Related Marine Protists
复制标题
对比混合营养生活方式揭示了两种密切相关的海洋原生生物的不同生态位
DOI：
10.1111/jpy.12920
复制
发表时间：
2019
影响因子：
2.9
通讯作者：
A. Worden
中科院分区：
文献类型：
--
作者：
Susanne Wilken;Chang Jae Choi;A. Worden
许多海洋微生物真核生物结合了联合收割机的光合作用和吞噬营养，但不完全了解这样的兼养原生生物，他们的功能多样性，和潜在的生理机制限制了评估和模拟他们在现在和未来的海洋生态系统中的作用。我们开发了一个实验系统，以研究的mixotrophic原生生物的可用性的活猎物和光的反应，并用它来表征对比的生理策略，在两个stratifiles属Ochromonas。我们表明，海洋分离CCMP1393是一个专性mixotrophs，需要光和猎物作为补充资源。CCMP 1393中光合作用和异养的相互依赖性包括线粒体呼吸在光合电子传递中的重要作用。相比之下，沿海分离物CCMP 2951是兼性兼养生物，可以通过吞噬替代光合作用，因此在黑暗中纯粹异养生长。与CCMP 1393相比，CCMP 2951还表现出显著的光保护反应，该反应整合了非光化学猝灭和线粒体呼吸，作为光合作用产生的还原当量的电子汇。类似于CCMP2951的兼性混合营养体可能很好地适应了可变的环境，而类似于CCMP1393的专性混合营养体似乎能够在贫营养海洋环境中资源有效地生长。因此，这些共生关系密切的原生生物对不同资源的可用性的反应揭示了影响食物网影响的生态位分化，并导致相反的碳循环作用。
Many marine microbial eukaryotes combine photosynthetic with phagotrophic nutrition, but incomplete understanding of such mixotrophic protists, their functional diversity, and underlying physiological mechanisms limits the assessment and modeling of their roles in present and future ocean ecosystems. We developed an experimental system to study responses of mixotrophic protists to availability of living prey and light, and used it to characterize contrasting physiological strategies in two stramenopiles in the genus Ochromonas. We show that oceanic isolate CCMP1393 is an obligate mixotroph, requiring both light and prey as complementary resources. Interdependence of photosynthesis and heterotrophy in CCMP1393 comprises a significant role of mitochondrial respiration in photosynthetic electron transport. In contrast, coastal isolate CCMP2951 is a facultative mixotroph that can substitute photosynthesis by phagotrophy and hence grow purely heterotrophically in darkness. In contrast to CCMP1393, CCMP2951 also exhibits a marked photoprotection response that integrates non‐photochemical quenching and mitochondrial respiration as electron sink for photosynthetically produced reducing equivalents. Facultative mixotrophs similar to CCMP2951 might be well adapted to variable environments, while obligate mixotrophs similar to CCMP1393 appear capable of resource efficient growth in oligotrophic ocean environments. Thus, the responses of these phylogenetically close protists to the availability of different resources reveals niche differentiation that influences impacts in food webs and leads to opposing carbon cycle roles.
影响因子：
2.1
作者：
Leles, Suzana Goncalves;Polimene, Luca;Flynn, Kevin John
通讯作者：
Flynn, Kevin John
影响因子：
3.3
作者：
Hartmann, Manuela;Zubkov, Mikhail V.;Lepere, Cecile
通讯作者：
Lepere, Cecile
DOI：
10.1073/pnas.1118179109
发表时间：
2012-04-10
影响因子：
11.1
作者：
Hartmann, Manuela;Grob, Carolina;Zubkov, Mikhail V.
通讯作者：
Zubkov, Mikhail V.