Effect of ammonium and ferricyanide on nitrate utilization by Chlorella vulgaris
E K Pistorius1, E A Funkhouser, H Voss
1Forschungsstelle Vennesland der Max-Planck-Gesellschaft, Harnackstraße 23, D-1000, Berlin 33.
Abstract:
It has been shown previously that added ammonium salts cause a cessation of nitrate utilization in some Chlorella species. It has also been shown that Chlorella vulgaris can form an inactivated nitrate reductase which is an HCN complex. In the present study, a comparison has been made of the rate of nitrate utilization and the rate of nitrate reductase inactivation in Chlorella vulgaris in response to the addition of ammonium salts and light-dark changes. The rate of formation of HCN-inactivated enzyme is too slow to account for the prompt inhibition of nitrate utilization caused by adding ammonium. In contrast, when nitrate utilization is inhibited by addition of ferricyanide to intact cells, the HCN-inactivated enzyme is promptly formed in vivo, and might account for the inhibition of nitrate utilization, though inhibition of nitrate uptake can not be excluded.
Related Concept Videos
Metabolism of Chemolithotrophs
Inorganic Nitrogen Assimilation
2° Amines to N-Nitrosamines: Reaction with NaNO2
Microbial Nutrition
Overview of Nitrogen Metabolism
The largest pool of nitrogen available in the terrestrial ecosystem is gaseous nitrogen (N2) from the air, but this...
1° Amines to Diazonium or Aryldiazonium Salts: Diazotization with NaNO2 Overview
The nitrous acid is unstable. Hence, it is formed in situ from a solution of sodium nitrite and cold aqueous acids such as hydrochloric or sulfuric acid. In an acidic solution, the –OH group of nitrous acid undergoes protonation to give oxonium ion, followed by...


