ACETATE AS A CALCIUM-SPARING FACTOR IN NITROGEN FIXATION BY AZOTOBACTER VINELANDII

Nitrogen Fixation by Azotobacter vinelandii

Nitrogenase was isolated and purified from wildtype and a tungsten-resistant mutant (LM2) of Azotobacter vinelandii strain OP derepressed on medium containing 1-10 mM W. While the enzyme from the wild-type strain contained the polypeptides of the conventional enzyme, metal analysis of component 1 demonstrated the existence of one atom each of molybdenum and tungsten. Furthermore, the ESR spectr...

Evidence for an alternative nitrogen fixation system in Azotobacter vinelandii.

Two Azotobacter vinelandii strains capable of growing on N2(Nif+) were isolated from two different mutant strains that lacked dinitrogenase activity (Nif-). Extracts of N2-grown cells of the two Nif+ strains lacked significant amounts of the "conventional" dinitrogenase protein subunits, as determined by two-dimensional gel electrophoresis. Instead, the extracts contained at least four new prot...

Hydroxylamine as a Source of Nitrogen for Azotobacter Vinelandii.

Nitrogen Fixation: Hydrosulfite as Electron Donor with Cell-free Preparations of Azotobacter Vinelandii and Rhodospirillum Rubrum.

23 The analyses reported in Table 1 indicate that the fragment I used by us had 7 or 8, rather than 6 disulfide bonds, leading to an even lower probability for return to the native structure by random reoxidation. 24 Anfinsen, C. B., E. Haber, M. Sela, and F. H. White, Jr., these PROCEEDINGS, 47, 1309 (1961). 25 Chen-Lu, T., D. Yu-Cang, and X. Geng-Jun, Sci. Sinica (Peking), 10, 332 (1961); see...

Dissociation Constant in Nitrogen Fixation by Azotobacter

6 Dodge originally used "A" and "a" to designate the two sex types in Neurospora crassa. Lindegren later substituted the symbols "+" and "-" for these. Because of the desirability of using the symbol + for the normal allele of a gene and also to designate a positive experimental result, we prefer Dodge's original designations. 4 Neither conversion of pimelic acid to p-aminobenzoic acid by the n...