The environmental controls that govern the end product of bacterial nitrate respiration
Kraft, B.; Tegetmeyer, H.E.; Sharma, R.; Klotz, M.G.; Ferdelman, T. G.; Hettich, R.L.; Strous, M.; Geelhoed, J.S. (2014). The environmental controls that govern the end product of bacterial nitrate respiration. Science (Wash.) 345(6197): 676-679. http://dx.doi.org/10.1126/science.1254070 In: Science (Washington). American Association for the Advancement of Science: New York, N.Y. ISSN 0036-8075; e-ISSN 1095-9203, more |  |
| Authors | | Top | - Kraft, B.
- Tegetmeyer, H.E.
- Sharma, R.
- Klotz, M.G.
| - Ferdelman, T. G.
- Hettich, R.L.
- Strous, M.
- Geelhoed, J.S., more
| |
| Abstract | In the biogeochemical nitrogen cycle, microbial respiration processes compete for nitrateas an electron acceptor. Denitrification converts nitrate into nitrogenous gas and thusremoves fixed nitrogen from the biosphere, whereas ammonification converts nitrate intoammonium, which is directly reusable by primary producers.We combined multiple parallellong-term incubations of marine microbial nitrate-respiring communities with isotopelabeling and metagenomics to unravel how specific environmental conditions select foreither process. Microbial generation time, supply of nitrite relative to nitrate, and thecarbon/nitrogen ratio were identified as key environmental controls that determinewhether nitrite will be reduced to nitrogenous gas or ammonium. Our results define themicrobial ecophysiology of a biogeochemical feedback loop that is key to global change,eutrophication, and wastewater treatment. |
|
