Evolution: A Fixed-Nitrogen Fix in the Early Ocean?
نویسندگان
چکیده
A new study asserts that a late evolutionary leap in cyanobacterial nitrogen fixation terminated a long history of nitrogen-limited primary production in the ocean--and contributed to a dramatic increase in biospheric oxygen coincident with the rise of animals.
منابع مشابه
Evolution of Photosynthesis and Biospheric Oxygenation Contingent Upon Nitrogen Fixation?
How photosynthesis by Precambrian cyanobacteria oxygenated Earth’s biosphere remains incompletely understood. Here it is argued that the oxic transition, which took place between approximately 2.3 Gyr and 0.5 Gyr ago, required a great proliferation of cyanobacteria, and this in turn depended on their ability to fix nitrogen via the nitrogenase enzyme system. However, the ability to fix nitrogen...
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Nitrogen is an essential element for the evolution of life as we know it, because it is found in avariety of biologically important molecules. Therefore, N is an important element to study from anexobiological perspective. In particular, “fixed nitrogen” is the biologically useful form of nitrogen.Fixed nitrogen is generally defined as “3, NH;, NO,, or N that is chemically bound to ...
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عنوان ژورنال:
- Current Biology
دوره 24 شماره
صفحات -
تاریخ انتشار 2014