Dependence of oxygen-tolerant nitrogenase activity on divalent cations in Azotobacter vinelandii.
AUTOR(ES)
Peterson, J B
RESUMO
Nitrogenase activity of washed Azotobacter vinelandii cells was enhanced by the addition of Ca2+ and Mg2+, and the enhancement increased with the O2 concentration. In assays provided with a level of O2 that was initially supraoptimal and inhibitory to nitrogenase activity, the addition of Ca2+ or Mg2+ affected both the maximum respiration rate (Vmax) of the cells and the apparent affinity [KS(O2)] of cell respiration for O2. Changes in these parameters correlated with changes in nitrogenase activity. Aeration-dependent increases in Vmax and KS(O2) were inhibited by rifampin and chloramphenicol and were also observed in ammonium-grown cultures.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=206012Documentos Relacionados
- Dependence of nitrogenase switch-off upon oxygen stress on the nitrogenase activity in Azotobacter vinelandii.
- Oxygen-tolerant Strain of Chlorella sorokiniana
- Oxygen-tolerant Strain of Chlorella sorokiniana
- Inhibition of nitrogenase activity by ammonium chloride in Azotobacter vinelandii.
- Cellular ATP levels and nitrogenase switchoff upon oxygen stress in chemostat cultures of Azotobacter vinelandii.