Active and dormant microorganisms on glacier surfaces.
Active and dormant microorganisms on glacier surfaces.
复制标题
冰川表面上活跃和休眠的微生物。
作者：
冰川和冰盖表面有各种各样的微生物群落，它们的活动（或不活动）影响着地球化学循环和冰的融化。冰上微生物忍受各种极端环境，包括资源稀缺，水的冰点上下频繁的温度波动，以及夏季的高紫外线照射，然后是冬季的数月完全黑暗。使微生物生命能够在极端环境中持续存在的一种策略是休眠，尽管休眠在自然环境中的微生物群落中普遍存在，但在冰川表面生态系统中尚未直接测量和量化。在这里，我们使用元条形码和元转录组学分析的组合，以及细胞特异性活性（BONCAT）孵育来评估冰岛和格陵兰冰川表面微生物群落的多样性和活性。我们还提出了一种新的冰川微生物生态模型，并模拟了理想化（i）冻结，（ii）解冻和（iii）冻融条件下冰川微生物群落的生理状态变化。我们发现，高比例（>50%）的细菌细胞在雪和冰表面上原位翻译活性，放线菌门，假单胞菌门和浮游菌门占主导地位的总的和活跃的社区组成，冰川微生物，即使在冷冻时，可以恢复翻译活性在解冻后24小时内。我们的数据表明，冰川微生物对自然环境中典型的动态和变化条件反应迅速。我们推断，冰川表面的生物学和地球化学是由短时间内发生的过程形成的（即，日）的时间尺度，因此容易受到气候变化驱动的冰川融化制度预期变化的影响。更好地了解冰川表面微生物的活动对于解决极地地区日益增长的气候变化问题以及将其用作潜在可居住的冰雪世界中生命的类似物至关重要。
Glacier and ice sheet surfaces host diverse communities of microorganisms whose activity (or inactivity) influences biogeochemical cycles and ice melting. Supraglacial microbes endure various environmental extremes including resource scarcity, frequent temperature fluctuations above and below the freezing point of water, and high UV irradiance during summer followed by months of total darkness during winter. One strategy that enables microbial life to persist through environmental extremes is dormancy, which despite being prevalent among microbial communities in natural settings, has not been directly measured and quantified in glacier surface ecosystems. Here, we use a combination of metabarcoding and metatranscriptomic analyses, as well as cell‐specific activity (BONCAT) incubations to assess the diversity and activity of microbial communities from glacial surfaces in Iceland and Greenland. We also present a new ecological model for glacier microorganisms and simulate physiological state‐changes in the glacial microbial community under idealized (i) freezing, (ii) thawing, and (iii) freeze–thaw conditions. We show that a high proportion (>50%) of bacterial cells are translationally active in‐situ on snow and ice surfaces, with Actinomycetota, Pseudomonadota, and Planctomycetota dominating the total and active community compositions, and that glacier microorganisms, even when frozen, could resume translational activity within 24 h after thawing. Our data suggest that glacial microorganisms respond rapidly to dynamic and changing conditions typical of their natural environment. We deduce that the biology and biogeochemistry of glacier surfaces are shaped by processes occurring over short (i.e., daily) timescales, and thus are susceptible to change following the expected alterations to the melt‐regime of glaciers driven by climate change. A better understanding of the activity of microorganisms on glacier surfaces is critical in addressing the growing concern of climate change in Polar regions, as well as for their use as analogues to life in potentially habitable icy worlds.
登录
查看更多内容
影响因子：
3.7
作者：
Bradley JA;Amend JP;LaRowe DE
通讯作者：
LaRowe DE
影响因子：
4.2
作者：
Buford Price, P.
通讯作者：
Buford Price, P.
影响因子：
6.7
作者：
Edwards, Arwyn;Pachebat, Justin A.;Sattler, Birgit
通讯作者：
Sattler, Birgit
影响因子：
3.2
作者：
Cook, Joseph Mitchell;Hodson, Andy J.;Irvine-Fynn, Tristram D. L.
通讯作者：
Irvine-Fynn, Tristram D. L.
影响因子：
2
作者：
Brown, Shawn P.;Olson, Bradley J. S. C.;Jumpponen, Ari
通讯作者：
Jumpponen, Ari