Jove
Visualize
Contact Us
JoVE
x logofacebook logolinkedin logoyoutube logo
ABOUT JoVE
OverviewLeadershipBlogJoVE Help Center
AUTHORS
Publishing ProcessEditorial BoardScope & PoliciesPeer ReviewFAQSubmit
LIBRARIANS
TestimonialsSubscriptionsAccessResourcesLibrary Advisory BoardFAQ
RESEARCH
JoVE JournalMethods CollectionsJoVE Encyclopedia of ExperimentsArchive
EDUCATION
JoVE CoreJoVE BusinessJoVE Science EducationJoVE Lab ManualFaculty Resource CenterFaculty Site
Terms & Conditions of Use
Privacy Policy
Policies

Related Concept Videos

Valence Bond Theory02:42

Valence Bond Theory

8.6K
Coordination compounds and complexes exhibit different colors, geometries, and magnetic behavior, depending on the metal atom/ion and ligands from which they are composed. In an attempt to explain the bonding and structure of coordination complexes, Linus Pauling proposed the valence bond theory, or VBT, using the concepts of hybridization and the overlapping of the atomic orbitals. According to VBT, the central metal atom or ion (Lewis acid) hybridizes to provide empty orbitals of suitable...
8.6K
Metal-Ligand Bonds02:51

Metal-Ligand Bonds

20.8K
The hemoglobin in the blood, the chlorophyll in green plants, vitamin B-12, and the catalyst used in the manufacture of polyethylene all contain coordination compounds. Ions of the metals, especially the transition metals, are likely to form complexes.
In these complexes, transition metals form coordinate covalent bonds, a kind of Lewis acid-base interaction in which both of the electrons in the bond are contributed by a donor (Lewis base) to an electron acceptor (Lewis acid). The Lewis acid in...
20.8K
Coordination Number and Geometry02:57

Coordination Number and Geometry

15.9K
For transition metal complexes, the coordination number determines the geometry around the central metal ion. Table 1 compares coordination numbers to molecular geometry. The most common structures of the complexes in coordination compounds are octahedral, tetrahedral, and square planar.
15.9K
Structural Isomerism02:34

Structural Isomerism

19.2K
Isomerism in Complexes
Isomers are different chemical species that have the same chemical formula. Structural isomerism of coordination compounds can be divided into two subcategories, the linkage isomers and coordination-sphere isomers.
Linkage isomers occur when the coordination compound contains a ligand that can bind to the transition metal center through two different atoms. For example, the CN− ligand can bind through the carbon atom or through the nitrogen atom. Similarly, SCN− can...
19.2K
Colors and Magnetism03:02

Colors and Magnetism

11.7K
Color in Coordination Complexes
When atoms or molecules absorb light at the proper frequency, their electrons are excited to higher-energy orbitals. For many main group atoms and molecules, the absorbed photons are in the ultraviolet range of the electromagnetic spectrum, which cannot be detected by the human eye. For coordination compounds, the energy difference between the d orbitals often allows photons in the visible range to be absorbed and emitted, which is seen as colors by the human...
11.7K

You might also read

Related Articles

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

Sort by
Same author

The Role of Iron-Hyponitrite Intermediates in Biology and Insights From Synthetic Model Complexes.

Chemistry (Weinheim an der Bergstrasse, Germany)·2026
Same author

N-N Coupling of Nitrosyl Ligands in a Dinitrosyl Iron Complex Mediated by Exogenous Acids.

Inorganic chemistry·2026
Same author

High-Valent Late Transition Metal-Oxo Complexes: Breaking Boundaries at the Oxo Wall and Beyond.

Chemical reviews·2026
Same author

Shining light on the mechanism of photochemical alkene formation in vitamin B<sub>12</sub>.

Chemical science·2026
Same author

Nitric Oxide Reduction at a Single Iron Site Facilitated by Second Coordination Sphere Hydrogen Bonding via a Putative Fe(IV)-Oxo Intermediate.

Journal of the American Chemical Society·2026
Same author

Preparation, Spectroscopic Characterization, and Reactivity of High-Valent Non-Oxo Co(IV) and Formally Co(V) Complexes.

JACS Au·2025

Related Experiment Video

Updated: Jul 11, 2025

Monitoring the Reductive and Oxidative Half-Reactions of a Flavin-Dependent Monooxygenase using Stopped-Flow Spectrophotometry
12:08

Monitoring the Reductive and Oxidative Half-Reactions of a Flavin-Dependent Monooxygenase using Stopped-Flow Spectrophotometry

Published on: March 18, 2012

15.2K

Exploring second coordination sphere effects in flavodiiron nitric oxide reductase model complexes.

Abigail J Bracken1, Hai T Dong1, Michael O Lengel1

  • 1Department of Chemistry, The University of Michigan, Ann Arbor, Michigan 48109-1055, USA. lehnertn@umich.edu.

Dalton Transactions (Cambridge, England : 2003)
|November 8, 2023
PubMed
Summary

Flavodiiron nitric oxide reductases (FNORs) use a second coordination sphere tyrosine to reduce nitric oxide (NO). This study explores how modifying the iron-iron distance and adding hydrogen bonds affects NO reduction mechanisms in model complexes.

More Related Videos

Preparation of SNS CobaltII Pincer Model Complexes of Liver Alcohol Dehydrogenase
06:31

Preparation of SNS CobaltII Pincer Model Complexes of Liver Alcohol Dehydrogenase

Published on: March 19, 2020

7.1K
Application of Genetically Encoded Fluorescent Nitric Oxide (NO&#8226;) Probes, the geNOps, for Real-time Imaging of NO&#8226; Signals in Single Cells
08:32

Application of Genetically Encoded Fluorescent Nitric Oxide (NO•) Probes, the geNOps, for Real-time Imaging of NO• Signals in Single Cells

Published on: March 16, 2017

12.9K

Related Experiment Videos

Last Updated: Jul 11, 2025

Monitoring the Reductive and Oxidative Half-Reactions of a Flavin-Dependent Monooxygenase using Stopped-Flow Spectrophotometry
12:08

Monitoring the Reductive and Oxidative Half-Reactions of a Flavin-Dependent Monooxygenase using Stopped-Flow Spectrophotometry

Published on: March 18, 2012

15.2K
Preparation of SNS CobaltII Pincer Model Complexes of Liver Alcohol Dehydrogenase
06:31

Preparation of SNS CobaltII Pincer Model Complexes of Liver Alcohol Dehydrogenase

Published on: March 19, 2020

7.1K
Application of Genetically Encoded Fluorescent Nitric Oxide (NO&#8226;) Probes, the geNOps, for Real-time Imaging of NO&#8226; Signals in Single Cells
08:32

Application of Genetically Encoded Fluorescent Nitric Oxide (NO•) Probes, the geNOps, for Real-time Imaging of NO• Signals in Single Cells

Published on: March 16, 2017

12.9K

Area of Science:

  • Bioinorganic Chemistry
  • Enzyme Mechanisms
  • Antimicrobial Resistance

Background:

  • Flavodiiron nitric oxide reductases (FNORs) are crucial for pathogen survival by detoxifying nitric oxide (NO), a key mammalian immune defense molecule.
  • Understanding FNORs' NO reduction mechanism is vital for developing new therapies against drug-resistant pathogens.
  • Previous studies highlighted the importance of a second coordination sphere (SCS) tyrosine in stabilizing intermediates during NO reduction.

Purpose of the Study:

  • To investigate the role of the iron-iron (Fe⋯Fe) distance in the N-N coupling step of NO reduction.
  • To explore how second coordination sphere (SCS) amide groups influence hydrogen bonding with bridging ligands and coordinated NO.
  • To synthesize and characterize diiron model complexes with systematically varied Fe⋯Fe distances and SCS amide functionalities.

Main Methods:

  • Synthesis of novel diiron complexes featuring H[BPMP] ligands functionalized with SCS amide groups.
  • Systematic variation of the Fe⋯Fe distance by controlling the number of bridging acetate ligands (0-2).
  • Investigation of NO reactivity using spectroscopic techniques (IR, EPR) to characterize iron-NO intermediates and Dinitrosyl Iron Complexes (DNICs).

Main Results:

  • The synthesized diiron complexes reacted with NO, forming stable iron(II)-NO adducts.
  • One-electron reduction of these adducts yielded Dinitrosyl Iron Complexes (DNICs), confirmed by IR and EPR spectroscopy.
  • The study establishes a platform to probe the influence of Fe⋯Fe distance and hydrogen bonding on NO reduction pathways.

Conclusions:

  • The developed model complexes provide insights into the mechanistic aspects of FNORs' NO detoxification.
  • This research lays the groundwork for designing targeted inhibitors or therapeutic strategies against NO-resistant pathogens.
  • Further studies can elucidate the precise contribution of Fe⋯Fe distances and SCS interactions in the catalytic cycle.