Nitrogen fixation by marine cyanobacteria.
Nitrogen fixation by marine cyanobacteria.
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DOI：
10.1016/j.tim.2010.12.004
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发表时间：
2011-04
影响因子：
15.9
通讯作者：
J. Zehr
中科院分区：
文献类型：
--
作者：
J. Zehr
海洋固氮量与反硝化作用导致的氮(N)损失之间的差异使得研究重点集中在鉴定固氮蓝藻和量化固氮蓝藻上。以前未被认识到的培养和未培养的单细胞蓝藻已经被发现广泛分布，有些具有非常不寻常的特性。未经培养的单细胞固氮蓝藻（UCYN-A）缺乏主要的代谢途径，包括三羧酸循环和进化氧的光系统II。海洋固氮蓝藻基因组在DNA水平上高度保守，遗传多样性通过基因组重排得以维持。主要的蓝藻群具有不同的生理和生态限制，导致高度可变的地理分布，这对海洋n循环预算有影响。
Discrepancies between estimates of oceanic N2fixation and nitrogen (N) losses through denitrification have focused research on identifying N2-fixing cyanobacteria and quantifying cyanobacterial N2fixation. Previously unrecognized cultivated and uncultivated unicellular cyanobacteria have been discovered that are widely distributed, and some have very unusual properties. Uncultivated unicellular N2-fixing cyanobacteria (UCYN-A) lack major metabolic pathways including the tricarboxylic acid cycle and oxygen-evolving photosystem II. Genomes of the oceanic N2-fixing cyanobacteria are highly conserved at the DNA level, and genetic diversity is maintained by genome rearrangements. The major cyanobacterial groups have different physiological and ecological constraints that result in highly variable geographic distributions, with implications for the marine N-cycle budget.