The Utilization of Nitrogen in Hydroxylamine and Oximes by Azotobacter vinelandii.

The utilization of nitrogen in various compounds by Clostridium pasteurianum.

In biological nitrogen fixation the key intermediate compound, defined as the end product of the fixation reaction and the initial reactant of assimilation, is believed to be either ammonia or hydroxylamine. Burris and Wilson (1945) noted that these two possibilities need not be mutually exclusive but may occur simultaneously, depending on the concentrations of the carbon compounds serving as a...

Hydroxylamine as a Source of Nitrogen for Azotobacter Vinelandii.

Action of Inhibitors on Hydrogenase in Azotobacter

The inhibitors usually associated with the activity of the cytochrome oxidase system-cyanide and carbon monoxide-are also effective in reducing the oxidation of H(2) by intact cells of Azotobacter vinelandii. The hydrogenase system is more sensitive to CO than is the respiratory system. Oxidation of a carbon source and of hydrogen by Azotobacter cells is inhibited in a quantitatively different ...

Relationship of nitrite and hydroxylamine reductases to nitrate assimilation and nitrogen fixation in Azotobacter agile.

The nitrogen fixation process has been recently reviewed by Wilson (1952), Burris (1956), Shug et al. (1956), and Gest et al. (1956). Although the characteristics of the over-all process in vivo are well known, neither the pathway nor the enzymatic steps has been established. On the other hand, a number of enzymes from bacteria, fungi and higher plants have been characterized which together can...

Respiratory Protection of Nitrogenase Activity in <Emphasis Type="Italic">Azotobacter vinelandii</Emphasis>Roles of the Terminal Oxidases

Nitrogen fixation by aerobic prokaryotes appears paradoxical: the nitrogen-fixing enzymes— nitrogenases—are notoriously oxygen-labile, yet many bacteria fix nitrogen aerobically. This review summarises the evidence that cytochrome bd, a terminal oxidase unrelated to the mitochondrial and many other bacterial oxidases, plays a crucial role in aerotolerant nitrogen fixation in Azotobacter vinelan...