Search research articles

ABOUT JoVE

Overview Leadership Blog JoVE Help Center

AUTHORS

Publishing Process Editorial Board Scope & Policies Peer Review FAQ Submit

LIBRARIANS

Testimonials Subscriptions Access Resources Library Advisory Board FAQ

RESEARCH

JoVE Journal Methods Collections JoVE Encyclopedia of Experiments Archive

EDUCATION

JoVE Core JoVE Business JoVE Science Education JoVE Lab Manual Faculty Resource Center Faculty Site

Terms & Conditions of Use

Related Concept Videos

What is Population Genetics?

What is Population Genetics?

A population is composed of members of the same species that simultaneously live and interact in the same area. When individuals in a population breed, they pass down their genes to their offspring. Many of these genes are polymorphic, meaning that they occur in multiple variants. Such variations of a gene are referred to as alleles. The collective set of all the alleles within a population is known as the gene pool.

Meiosis II

Meiosis II

Meiosis II is the second and final stage of meiosis. It relies on the haploid cells produced during meiosis I, each of which contain only 23 chromosomes—one from each homologous initial pair. Importantly, each chromosome in these cells is composed of two joined copies, and when these cells enter meiosis II, the goal is to separate such sister chromatids using the same microtubule-based network employed in other division processes. The result of meiosis II is two haploid cells, each...

Histone Variants at the Centromere

Histone Variants at the Centromere

Histone variants are the histone proteins with structural and sequence variations. These variants may be regarded as “mutant” forms that replace their canonical histone counterparts in the nucleosomes. Specific post-translational modifications on the histone variants enable further chromatin complexity and regulate tissue-specific gene expression. The most common histone variants are from histone H2A, H2B, and linker histone H1 families. However, several variants of histone H3...

The Representativeness Heuristic

The Representativeness Heuristic

The representative heuristic describes a biased way of thinking, in which you unintentionally stereotype someone or something. For example, you may assume that your professors spend their free time reading books and engaging in intellectual conversation, because the idea of them spending their time playing volleyball or visiting an amusement park does not fit in with your stereotypes of professors.

The Wave Nature of Light

The Wave Nature of Light

The nature of light has been a subject of inquiry since antiquity. In the seventeenth century, Isaac Newton performed experiments with lenses and prisms and was able to demonstrate that white light consists of the individual colors of the rainbow combined together. Newton explained his optics findings in terms of a "corpuscular" view of light, in which light was composed of streams of extremely tiny particles traveling at high speeds according to Newton's laws of motion.

Genomic Imprinting and Inheritance

Genomic Imprinting and Inheritance

Diploid organisms inherit genetic material through chromosomes from both parents. Copies of the same gene are known as alleles. In most cases, both alleles are simultaneously expressed and allow various cellular processes to function optimally. If one of the alleles is missing or mutated, the expression of the other allele can compensate; however, this is not true for all genes.
The expression of some genes depends on which parent passed the gene to the offspring, through a phenomenon known as...

You might also read

Related Articles

Articles linked to this work by shared authors, journal, and citation graph.

Sort by

Same author

A redox- and proton-coupled inner membrane transporter mediates copper import to the bacterial cytoplasm.

Proceedings of the National Academy of Sciences of the United States of America·2026

Same author

Sulfite Is Not Required for N<sub>2</sub> Reduction Catalyzed by Mo-Nitrogenase.

Journal of the American Chemical Society·2026

Same author

The radical SAM enzyme EpeE exhibits distinct site reactivity during the biosynthesis of the RiPP natural product epipeptide.

Proceedings of the National Academy of Sciences of the United States of America·2026

Same author

Simultaneous occupancy of Cu<sub>C</sub> and Cu<sub>D</sub> in the ammonia monooxygenase active site.

Chemical science·2026

Same author

EPR spectroscopy reveals antioxidant manganese defenses in the Lyme disease pathogen <i>Borrelia burgdorferi</i>.

mBio·2025

Same author

In vitro maturation of fully active [FeFe]-hydrogenase in a defined system including the iron carrier NfuA.

Proceedings of the National Academy of Sciences of the United States of America·2025

Search research articles

Related Experiment Video

Updated: Feb 5, 2026

A Method for Characterizing Embryogenesis in Arabidopsis

A Method for Characterizing Embryogenesis in Arabidopsis

Published on: August 4, 2017

ENDOR Characterization of (N

Hao Yang¹, Jonathan Rittle², Amy R Marts¹

¹Department of Chemistry , Northwestern University , Evanston , Illinois 60208 , United States.

Inorganic Chemistry

|September 18, 2018

Summary

This summary is machine-generated.

A biomimetic diiron complex models nitrogenase enzyme states, revealing insights into nitrogen (N2) reduction. This study confirms a delocalized mixed valency and uses hydride properties as a diagnostic signature for biological iron-sulfur clusters.

More Related Videos

Characterization of Aquatic Biofilms with Flow Cytometry

Characterization of Aquatic Biofilms with Flow Cytometry

Published on: June 6, 2018

Methods for Characterizing the Co-development of Biofilm and Habitat Heterogeneity

Methods for Characterizing the Co-development of Biofilm and Habitat Heterogeneity

Published on: March 11, 2015

Related Experiment Videos

Last Updated: Feb 5, 2026

A Method for Characterizing Embryogenesis in Arabidopsis

A Method for Characterizing Embryogenesis in Arabidopsis

Published on: August 4, 2017

Characterization of Aquatic Biofilms with Flow Cytometry

Characterization of Aquatic Biofilms with Flow Cytometry

Published on: June 6, 2018

Methods for Characterizing the Co-development of Biofilm and Habitat Heterogeneity

Methods for Characterizing the Co-development of Biofilm and Habitat Heterogeneity

Published on: March 11, 2015

Area of Science:

Bioinorganic Chemistry
Enzyme Mechanisms
Organometallic Chemistry

Background:

Nitrogenase is a crucial enzyme that reduces atmospheric nitrogen (N2) to ammonia.
Understanding nitrogenase mechanisms requires biomimetic models that replicate its active site.
The enzyme's catalytic cycle involves complex iron-sulfur clusters and hydride intermediates.

Purpose of the Study:

To model key intermediates in the nitrogenase catalytic cycle using a biomimetic diiron complex.
To investigate the electronic structure and bonding of a diiron complex with bound N2 and bridging hydrides.
To establish diagnostic signatures for identifying similar structures in biological systems.

Main Methods:

Synthesis of a biomimetic diiron complex, 4-(N2)2.
1H and 14N 35 GHz ENDOR spectroscopy.
Analysis using a point-dipole model for dipolar interactions.

Main Results:

The diiron complex exhibits a Robin-Day type-III mixed valency, indicating delocalized electrons.
Bridging hydrides show a rhombic dipolar tensor, serving as a diagnostic signature for biological iron centers.
Spectroscopic analysis provides insights into charge transfer between iron and coordinated nitrogen.

Conclusions:

The biomimetic complex accurately models key states of nitrogenase, including the Janus intermediate.
The rhombic hydride signature is a valuable tool for studying nitrogenase and related metalloenzymes.
This work advances the understanding of N2 activation and reduction mechanisms in biological systems.