Expression of hydrogenase activity in free-living Rhizobium japonicum.

  title={Expression of hydrogenase activity in free-living Rhizobium japonicum.},
  author={Robert J Maier and N F Campbell and F. Joe Hanus and Frank B. Simpson and Sterling A. Russell and H. J. Evans},
  journal={Proceedings of the National Academy of Sciences of the United States of America},
  volume={75 7},
A medium is described on which selected Rhizobium japonicum strains express hydrogenase (H(2) uptake) activity under free-living conditions. Low concentrations of carbon substrates, decreased oxygen tension, and the quantity of combined nitrogen in the medium were major factors influencing hydrogenase expression. Hydrogenase activity was dependent upon a preincubation period in the presence of H(2) under conditions such that the cells did not exhibit nitrogenase activity. H(2) uptake rates were… CONTINUE READING