Another iron in the fire: X-ray anomalous diffraction studies on the nitrogenase MoFe protein show the presence of a mononuclear iron site, designated as Fe16, which was previously identified as either Ca(2+) or Mg(2+). The position of the absorption edge indicates that this site is in the oxidation state +2. The high sequence conservation of the residues coordinated to Fe16 emphasizes the potential importance of the site in nitrogenase.
Download full-text PDF |
Source |
|---|---|
| http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3891402 | PMC |
| http://dx.doi.org/10.1002/anie.201303877 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Investigating the Molybdenum Nitrogenase Mechanistic Cycle Using Spectroelectrochemistry.
J Am Chem Soc
January 2025
Department of Inorganic Spectroscopy, Max Planck Institute for Chemical Energy Conversion, Mülheim an der Ruhr, Germany, 45470.
Molybdenum nitrogenase plays a crucial role in the biological nitrogen cycle by catalyzing the reduction of dinitrogen (N) to ammonia (NH) under ambient conditions. However, the underlying mechanisms of nitrogenase catalysis, including electron and proton transfer dynamics, remain only partially understood. In this study, we covalently attached molybdenum nitrogenase (MoFe) to gold electrodes and utilized surface-enhanced infrared absorption spectroscopy (SEIRA) coupled with electrochemistry techniques to investigate its catalytic mechanism.
View Article and Find Full Text PDFNifEN: a versatile player in nitrogenase assembly, catalysis and evolution.
J Biol Inorg Chem
December 2024
Department of Molecular Biology and Biochemistry, University of California, Irvine, CA, 92697-3900, USA.
The Mo-nitrogenase catalyzes the reduction of N to NH at the cofactor of its catalytic NifDK component. NifEN shares considerable homology with NifDK in primary sequence, tertiary structure and associated metallocenters. Better known for its biosynthetic function to convert an all-iron precursor (L-cluster; [FeSC]) to a mature cofactor (M-cluster; [(R-homocitrate) MoFeSC]), NifEN also mimics NifDK in catalyzing substrate reduction at ambient conditions.
View Article and Find Full Text PDFAZ0019 requires functional gene for optimal plant growth promotion in tomato plants.
Front Plant Sci
November 2024
The University of Nottingham, School of Biosciences, Division Microbiology, Brewing and Biotechnology, Sutton Bonington, Leicestershire, United Kingdom.
Article Synopsis
- A nitrogen-fixing bacterium is examined for its ability to enhance the growth of tomato plants, focusing on its colonization methods and growth promotion capabilities.
- The study compares a wild type strain (Gd WT) with a nitrogen fixation-impaired mutant (Gd -), assessing their effects on plant growth under different nitrogen conditions.
- Results show that Gd WT significantly improves plant height, weight, and chlorophyll content, demonstrating the importance of the nitrogen-fixing gene for optimal plant growth promotion.
Structural evolution of nitrogenase states under alkaline turnover.
Nat Commun
December 2024
Division of Chemistry and Chemical Engineering 147-75 California Institute of Technology, Pasadena, CA, USA.
Biological nitrogen fixation, performed by the enzyme nitrogenase, supplies nearly 50% of the bioavailable nitrogen pool on Earth, yet the structural nature of the enzyme intermediates involved in this cycle remains ambiguous. Here we present four high resolution cryoEM structures of the nitrogenase MoFe-protein, sampled along a time course of alkaline reaction mixtures under an acetylene atmosphere. This series of structures reveals a sequence of salient changes including perturbations to the inorganic framework of the FeMo-cofactor; depletion of the homocitrate moiety; diminished density around the S2B belt sulfur of the FeMo-cofactor; rearrangements of cluster-adjacent side chains; and the asymmetric displacement of the FeMo-cofactor.
View Article and Find Full Text PDFUnderstanding the P-Cluster of Vanadium Nitrogenase: an EPR and XAS Study of the Holo vs. Apo Forms of the Enzyme.
Chembiochem
November 2024
Department of Inorganic Spectroscopy, Max Planck Institute for Chemical Energy Conversion, Stiftstrasse 34-36, Mülheim an der Ruhr, 45470, Germany.
Article Synopsis
- The nitrogenase enzyme has two critical metalloclusters: the M-cluster for substrate reduction and the P-cluster for electron transfer, with ongoing debates about the structure of the P-cluster in the VFe protein.
- Using the apo-form of VFe, researchers found that its P-cluster is heterogeneous and retains components but not a fully formed structure, as shown through SDS-PAGE and NativePAGE analyses.
- EPR measurements indicated varying intensity signals at g=12 for different samples, suggesting that the P-cluster structure varies depending on the nitrogenase form and may indicate fragmentation in the apo-VFe's iron-sulfur clusters.
Want AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!