"Beijerinckia derxii" stimulates the viability of non-N(2)-fixing bacteria in nitrogen-free media

The interactions between the nitrogen-fixing microorganism "Beijerinckia derxii" with two non-diazotrophic bacteria, either "Escherichia coli" or a faculty sulphur-oxidizing chemolitroph, were studied in mixed cultures. Direct and indirect contact between "B. derxii" and "E. coli" were tested. "B. derxii" increased CFU numbers and/or maintained the viability of the non-diazotrophic bacteria, but neither growth nor nitrogenase activity of the nitrogen-fixing bacterium were affected by either partner