Life on Earth depends on N2‐fixing microbes to make ammonia from atmospheric N2gas by the nitrogenase enzyme. Most nitrogenases use Mo as a cofactor; however, V and Fe are also possible. N2fixation was once believed to have evolved during the Archean‐Proterozoic times using Fe as a cofactor. However, δ15N values of paleo‐ocean sediments suggest Mo and V cofactors despite their low concentrations in the paleo‐oceans. This apparent paradox is based on an untested assumption that only soluble metals are bioavailable. In this study, laboratory experiments were performed to test the bioavailability of mineral‐associated trace metals to a model N2‐fixing bacterium
- Award ID(s):
- 1631814
- NSF-PAR ID:
- 10192517
- Date Published:
- Journal Name:
- Applied and Environmental Microbiology
- Volume:
- 86
- Issue:
- 19
- ISSN:
- 0099-2240
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1128/AEM.00849-20
