Globally distributed uncultivated oceanic N2-fixing cyanobacteria lack oxygenic photosystem II.
نویسندگان
چکیده
Biological nitrogen (N2) fixation is important in controlling biological productivity and carbon flux in the oceans. Unicellular N2-fixing cyanobacteria have only recently been discovered and are widely distributed in tropical and subtropical seas. Metagenomic analysis of flow cytometry-sorted cells shows that unicellular N2-fixing cyanobacteria in "group A" (UCYN-A) lack genes for the oxygen-evolving photosystem II and for carbon fixation, which has implications for oceanic carbon and nitrogen cycling and raises questions regarding the evolution of photosynthesis and N2 fixation on Earth.
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ورودعنوان ژورنال:
- Science
دوره 322 5904 شماره
صفحات -
تاریخ انتشار 2008