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 Experiment Videos

Cyanamide: a new substrate for nitrogenase.

R W Miller1, R R Eady

  • 1Plant Research Centre, Agriculture Canada, Ottawa.

Biochimica Et Biophysica Acta
|February 10, 1988
PubMed
Summary
This summary is machine-generated.

Related Concept Videos

You might also read

Related Articles

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

Sort by
Same author

The Future of Radioactive Medicine.

Radiation research·2023
Same author

Occurrence ofCis-6-hexadecenoic acid as the major component ofThunbergia alata seed oil.

Lipids·2016
Same author

Biological Control of the Pecan Weevil, Curculio caryae (Coleoptera: Curculionidae), with Entomopathogenic Nematodes.

Journal of nematology·2009
Same author

Advances in 4D medical imaging and 4D radiation therapy.

Technology in cancer research & treatment·2008
Same author

A two-faced molecule offers NO explanation: the proximal binding of nitric oxide to haem.

Biochemical Society transactions·2003
Same author

Optically stimulated luminescent glass optical fibre dosemeter.

Radiation protection dosimetry·2002
Same journal

Cumulative Contents.

Biochimica et biophysica acta·2020
Same journal

Molecular Basis of Disease Cumulative Contents.

Biochimica et biophysica acta·2020
Same journal

General Subjects Cumulative Contents.

Biochimica et biophysica acta·2020
Same journal

Erratum to 'on the role of exchangeable hydrogen bonds for the kinetics of P680<sup>+·</sup> Q<sub>A</sub> <sup>-·</sup> formation and P680<sup>+·</sup> Pheo<sup>-·</sup> recombination in photosystem II' [Biochim. Biophys. Acta 1276 (1996) 35-44].

Biochimica et biophysica acta·2019
Same journal

Oligomeric state of the light-harvesting complexes B800-850 and B875 from purple bacterium Rubrivivax gelatinosus in detergent solution.

Biochimica et biophysica acta·2019
Same journal

Regulation of pigment content and enzyme activity in the cyanobacterium Nostoc sp. Mac grown in continuous light, a light-dark photoperiod, or darkness.

Biochimica et biophysica acta·2019
See all related articles

Cyanamide is a substrate for Mo-nitrogenases and Va-nitrogenases, yielding methane and ammonia. It inhibits nitrogenase activity, suggesting a role in regulating nitrogen fixation processes.

Area of Science:

  • Biochemistry
  • Microbiology
  • Enzymology

Background:

  • Nitrogenases are crucial enzymes for converting atmospheric nitrogen into ammonia.
  • Understanding alternative substrates and inhibitors of nitrogenase is vital for nitrogen cycle research.

Purpose of the Study:

  • To investigate cyanamide as a substrate and inhibitor for molybdenum (Mo)-nitrogenases and vanadium (Va)-nitrogenases.
  • To elucidate the reduction products and pathways of cyanamide metabolism by nitrogenases.

Main Methods:

  • Enzyme kinetics studies using purified Mo-nitrogenases from Klebsiella pneumoniae and Azotobacter chroococcum.
  • Characterization of cyanamide reduction products and electron requirements.
  • Assays with Va-nitrogenase from A. chroococcum to compare substrate binding and activity.

Related Experiment Videos

  • Inhibition studies on acetylene reduction and hydrogen evolution.

    • Main Results:

    • Cyanamide is a substrate for Mo-nitrogenases (Km ~0.8 mM) and Va-nitrogenase (Km ~2.6 mM), with Mo-nitrogenases showing stronger binding.
    • Reduction products include methane, methylamine, and ammonia, requiring 6 or 8 electrons.
    • Cyanamide significantly inhibits nitrogenase activity (acetylene reduction, H2 evolution) and electron flux.
    • Va-nitrogenase exhibits lower Vmax for cyanamide compared to Mo-nitrogenases.

    Conclusions:

    • Cyanamide serves as an alternative substrate for both Mo- and Va-nitrogenases.
    • Cyanamide acts as an inhibitor of nitrogenase function, impacting key enzymatic processes.
    • The findings provide insights into nitrogenase substrate diversity and regulatory mechanisms.