• 主题
高级搜索  >
历史搜索 清空历史
首页> 美国卫生研究院文献>other >Diazotroph Diversity in the Sea Ice Melt Ponds and Surface Waters of the Eurasian Basin of the Central Arctic Ocean
【2h】

Diazotroph Diversity in the Sea Ice Melt Ponds and Surface Waters of the Eurasian Basin of the Central Arctic Ocean

机译：北冰洋欧亚盆地海冰熔池和地表水中的重氮营养多样性

代理获取
本网站仅为用户提供外文OA文献查询和代理获取服务，本网站没有原文。下单后我们将采用程序或人工为您竭诚获取高质量的原文，但由于OA文献来源多样且变更频繁，仍可能出现获取不到、文献不完整或与标题不符等情况，如果获取不到我们将提供退款服务。请知悉。
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

The Eurasian basin of the Central Arctic Ocean is nitrogen limited, but little is known about the presence and role of nitrogen-fixing bacteria. Recent studies have indicated the occurrence of diazotrophs in Arctic coastal waters potentially of riverine origin. Here, we investigated the presence of diazotrophs in ice and surface waters of the Central Arctic Ocean in the summer of 2012. We identified diverse communities of putative diazotrophs through targeted analysis of the nifH gene, which encodes the iron protein of the nitrogenase enzyme. We amplified 529 nifH sequences from 26 samples of Arctic melt ponds, sea ice and surface waters. These sequences resolved into 43 clusters at 92% amino acid sequence identity, most of which were non-cyanobacterial phylotypes from sea ice and water samples. One cyanobacterial phylotype related to Nodularia sp. was retrieved from sea ice, suggesting that this important functional group is rare in the Central Arctic Ocean. The diazotrophic community in sea-ice environments appear distinct from other cold-adapted diazotrophic communities, such as those present in the coastal Canadian Arctic, the Arctic tundra and glacial Antarctic lakes. Molecular fingerprinting of nifH and the intergenic spacer region of the rRNA operon revealed differences between the communities from river-influenced Laptev Sea waters and those from ice-related environments pointing toward a marine origin for sea-ice diazotrophs. Our results provide the first record of diazotrophs in the Central Arctic and suggest that microbial nitrogen fixation may occur north of 77°N. To assess the significance of nitrogen fixation for the nitrogen budget of the Arctic Ocean and to identify the active nitrogen fixers, further biogeochemical and molecular biological studies are needed.
机译：北冰洋中部的欧亚盆地受到氮的限制，但对固氮细菌的存在和作用知之甚少。最近的研究表明，潜在的河流起源是在北极沿海水域中出现重氮菌。在这里，我们调查了2012年夏季在北冰洋中部和冰和表层水中存在的重氮营养菌。我们通过对nifH基因进行了靶向分析，确定了推定的重氮营养菌群落，该基因编码了氮酶的铁蛋白。我们从26个北极融化池，海冰和地表水样本中扩增了529个nifH序列。这些序列以92％的氨基酸序列同一性分解为43个簇，其中大多数是来自海冰和水样品的非蓝细菌系统型。一种与结节藻有关的蓝细菌系统型。是从海冰中检索到的，表明这个重要的功能群在北冰洋中很少见。海冰环境中的重氮营养群落与其他冷适应的重氮营养群落似乎截然不同，例如存在于加拿大沿海北极地区，北极苔原和冰河南极湖泊中的那些。 nifH和rRNA操纵子的基因间隔区的分子指纹图谱揭示了受河流影响的Laptev海水和那些与冰相关环境的群落之间的差异，这些群落指向海洋起源的海冰重氮菌。我们的结果提供了中部北极重氮菌的第一个记录，并表明微生物固氮可能发生在77°N以北。为了评估固氮对北冰洋氮预算的重要性并确定活性固氮剂，需要进一步的生物地球化学和分子生物学研究。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
代理获取

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号