Nitrogenase Cofactor Maturase NifB Isolated from Transgenic Rice is Active in FeMo-co Synthesis

The engineering of nitrogen fixation in plants requires assembly of an active prokaryotic nitrogenase complex, which is yet to be achieved. Nitrogenase biogenesis relies on NifB, which catalyzes the formation of the [8Fe−9S−C] metal cluster NifB-co. This is the first committed step in the biosynthes...

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Detalhes bibliográficos
Autores: He, Wenshu, Burén, Stefan, Baysal, Can, Jiang, Xi, Capell Capell, Teresa, Christou, Paul, Rubio, Luis
Formato: artículo
Estado:Versión publicada
Fecha de publicación:2022
País:España
Recursos:Varias* (Consorci de Biblioteques Universitáries de Catalunya, Centre de Serveis Científics i Acadèmics de Catalunya)
Repositorio:Recercat. Dipósit de la Recerca de Catalunya
OAI Identifier:oai:recercat.cat:10459.1/84460
Acesso em linha:https://doi.org/10.1021/acssynbio.2c00194
http://hdl.handle.net/10459.1/84460
Access Level:acceso abierto
Palavra-chave:Nitrogen fixation
Transgenic rice
NifB-co
Synthetic biology
Iron-molybdenum cofactor
Descrição
Resumo:The engineering of nitrogen fixation in plants requires assembly of an active prokaryotic nitrogenase complex, which is yet to be achieved. Nitrogenase biogenesis relies on NifB, which catalyzes the formation of the [8Fe−9S−C] metal cluster NifB-co. This is the first committed step in the biosynthesis of the iron−molybdenum cofactor (FeMo-co) found at the nitrogenase active site. The production of NifB in plants is challenging because this protein is often insoluble in eukaryotic cells, and its [Fe−S] clusters are extremely unstable and sensitive to O2. As a first step to address this challenge, we generated transgenic rice plants expressing NifB from the Archaea Methanocaldococcus infernus and Methanothermobacter thermautotrophicus. The recombinant proteins were targeted to the mitochondria to limit exposure to O2 and to have access to essential [4Fe−4S] clusters required for NifB-co biosynthesis. M. infernus and M. thermautotrophicus NifB accumulated as soluble proteins in planta, and the purified proteins were functional in the in vitro FeMo-co synthesis assay. We thus report NifB protein expression and purification from an engineered staple crop, representing a first step in the biosynthesis of a functional NifDK complex, as required for independent biological nitrogen fixation in cereals.