HYDROXYLAMINE AS A SOURCE OF NITROGEN FOR AZOTOBACTER VINELANDII

Publisher Website
Google Scholar
Abstract
Burk and Horner (Naturwissenschaften, 23: 259. 1935) found in short-time micro-respiration expts. that A. vinelandii did not use the N of hydroxylamine. Recent studies by Novak and Wilson (Jour. Bact., 55: 517. 1948) indicated that on prolonged incubation this organism would grow when NH2OH was the sole source of N even when N fixation was eliminated by incubation in an atmosphere of H2 + 02. Initiation of growth was delayed, however, dependent on the initial concn. of NH2OH. Decomposition of the NH2OH to a nontoxic compound was suspected; in these expts. this explanation was demonstrated to be true and the nontoxic compound shown to be ammonia. Because of this instability of hydroxylamine in dilute soln. it is not possible to carry out expts. with labelled nitrogen in NH2OH or its oximes. In conventional growth expts., however, it was demonstrated that even in long-time expts. neither NH2OH nor its oximes could be used as a source of N. This was true even though nontoxic levels of the compounds were present. Hydroxylamine is not a likely intermediate in N fixation by Azotobacter.