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Medical AI Inquiry: You was designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.  Labels: OBJECTIVE, RESULTS. Meshes: Amino Acids, Beijerinckiaceae, Culture Media, Ethylenes, Indoleacetic Acids, Nitrogenase, Plant Growth Regulators, Polyamines, Putrescine, Soil Microbiology, Spermidine.
user
Does beijerinckia derxii release plant growth regulators and amino acids in synthetic media independent of nitrogenase activity? Context: This study aims at evaluating the ability of Beijerinckia derxii, a free-living nitrogen (N)-fixing bacterium frequently isolated from tropical soils, to release certain plant growth regulators [indoleacetic acid (IAA), ethylene, polyamines] and amino acids into the growth medium. The production of those substances was compared using both cultures in which nitrogenase was active (N-free medium) and cultures in which nitrogenase was repressed (combined-N cultures). Those cultures were grown under agitation and in absence of agitation. Total IAA production was higher in agitated, N-free cultures but specific production was greater in combined-N cultures under agitation. Putrescine and spermidine were detected under all conditions tested. Ethylene was produced in both N-free and combined-N cultures. A greatest diversity of amino acids was released in N-free cultures.
assistant
There was no inhibition of the production of the analysed substances under conditions where nitrogenase was inactive. Final Decision: yes