Assays of Nitrogenase Reaction Products

  • William E. NewtonEmail author
  • Michael J. Dilworth
Part of the Methods in Molecular Biology book series (MIMB, volume 766)


Steady-state assays of nitrogenases share at least five requirements: an anaerobic environment, a consistent source of magnesium adenosine triphosphate (MgATP), a suitable source of reductant, a buffer system compatible with the product-quantification protocol to be used, and the desired substrate. The assay is initiated by injection of the component protein(s) of the enzyme or MgATP and terminated by injection of either acid or a solution of Na2EDTA. The various nitrogenases catalyze the reduction of a wide variety of substrates. This chapter outlines the methods used to analyze the products of nitrogenase-catalyzed reactions involving nitrogen–nitrogen bonds, nitrogen–oxygen bonds, carbon–nitrogen bonds, carbon–carbon bonds, carbon–oxygen bonds, carbon–sulfur bonds, and hydrogen only. The usefulness of measurements of residual amounts of other components of nitrogenase assays is also discussed.

Key words

Nitrogenase substrate catalysis steady-state assays electron balance 


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© Springer Science+Business Media, LLC 2011

Authors and Affiliations

  1. 1.Department of BiochemistryVirginia Polytechnic Institute & State UniversityBlacksburgUSA
  2. 2.School of Biological Sciences and Biotechnology, Center for Rhizobium Studies, Murdoch UniversityMurdochAustralia

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