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. 1969 Nov;115(3):529–535. doi: 10.1042/bj1150529

The relationship between nitrogen fixation and the production of HD from D2 by cell-free extracts of soya-bean nodule bacteroids

G L Turner 1, F J Bergersen 1
PMCID: PMC1185134  PMID: 5353527

Abstract

1. Cell-free extracts prepared from soya-bean nodule bacteroids produced HD from D2 in the presence of dithionite, an ATP-generating system and nitrogen. 2. Crude extracts of bacteroids or of Azotobacter vinelandii showed some background D2 exchange when any one of these was omitted. 3. Partial purification of bacteroid extracts diminished this background activity and gave increased D2 exchange and nitrogen fixation. 4. Although increasing pN2 stimulated both reactions, the apparent Km (N2) for nitrogen fixation was much higher than the apparent Km (N2) for D2 exchange when partially purified bacteroid extracts were used. 5. Carbon monoxide was a competitive inhibitor of nitrogen fixation by partially purified bacteroid extracts, but D2 exchange was inhibited in a non-competitive fashion. 6. These results are discussed in relation to the possible existence of enzyme-bound intermediates of nitrogen fixation.

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Selected References

These references are in PubMed. This may not be the complete list of references from this article.

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