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A 192-heme electron transfer network in the hydrazine dehydrogenase complex

Anaerobic ammonium oxidation (anammox) is a major process in the biogeochemical nitrogen cycle in which nitrite and ammonium are converted to dinitrogen gas and water through the highly reactive intermediate hydrazine. So far, it is unknown how anammox organisms convert the toxic hydrazine into nitr...

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Detalles Bibliográficos
Autores principales: Akram, M., Dietl, A., Mersdorf, U., Prinz, S., Maalcke, W., Keltjens, J., Ferousi, C., de Almeida, N. M., Reimann, J., Kartal, B., Jetten, M. S. M., Parey, K., Barends, T. R. M.
Formato: Online Artículo Texto
Lenguaje:English
Publicado: American Association for the Advancement of Science 2019
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6469936/
https://www.ncbi.nlm.nih.gov/pubmed/31001586
http://dx.doi.org/10.1126/sciadv.aav4310
Descripción
Sumario:Anaerobic ammonium oxidation (anammox) is a major process in the biogeochemical nitrogen cycle in which nitrite and ammonium are converted to dinitrogen gas and water through the highly reactive intermediate hydrazine. So far, it is unknown how anammox organisms convert the toxic hydrazine into nitrogen and harvest the extremely low potential electrons (−750 mV) released in this process. We report the crystal structure and cryo electron microscopy structures of the responsible enzyme, hydrazine dehydrogenase, which is a 1.7 MDa multiprotein complex containing an extended electron transfer network of 192 heme groups spanning the entire complex. This unique molecular arrangement suggests a way in which the protein stores and releases the electrons obtained from hydrazine conversion, the final step in the globally important anammox process.