Send to:

Choose Destination
See comment in PubMed Commons below
J Biol Chem. 1983 Oct 10;258(19):12064-8.

Electron transport to nitrogenase. Purification and characterization of pyruvate:flavodoxin oxidoreductase. The nifJ gene product.


Pyruvate:flavodoxin oxidoreductase, the nifJ gene product of Klebsiella pneumoniae, was purified to homogeneity. Pyruvate:flavodoxin oxidoreductase, flavodoxin, and nitrogenase components I and II are the only proteins required for pyruvate-coupled nitrogenase activity. The physiological source of electrons to nitrogenase in K. pneumoniae is pyruvate. Flavodoxin from Azotobacter vinelandii was only one-third as effective as K. pneumoniae flavodoxin in transferring electrons from pyruvate:flavodoxin oxidoreductase to Azotobacter and Klebsiella nitrogenases. Ferredoxins from aerobic, anaerobic and photosynthetic nitrogen-fixing organisms, as well as benzyl viologen and methyl viologen, were ineffective in coupling pyruvate oxidation to nitrogenase activity. One mol each of acetyl-CoA, CO2, and ethylene are formed by pyruvate-supported acetylene reduction. The enzyme contains 8.0 +/- 0.6 mol of iron and 6.6 +/- 0.2 mol of acid-labile sulfide per mol of protein (Mr = 240,000). Pyruvate:flavodoxin oxidoreductase is irreversibly inactivated by air.

[PubMed - indexed for MEDLINE]
Free full text
PubMed Commons home

PubMed Commons

How to join PubMed Commons

    Supplemental Content

    Full text links

    Icon for HighWire
    Loading ...
    Write to the Help Desk