Regulation of nitrogenase activity in soybean nodules by ATP and energy charge |
| |
Authors: | Te May Ching |
| |
Affiliation: | Crop Science Department Oregon State University Corvallis, OR 97331, USA |
| |
Abstract: | Nonphosphorylating condition under anaerobiosis stopped nitrogenase activity in nodules of soybean ( var. Chippewa) in less than three minutes and aeration quickly activated the enzyme. This stop-and-go treatment can be repeatedly applied on excised nodules, and a concomitant low-and-high ATP and energy charge (EC) was observed. After 2 minutes under anaerobiosis, nodule ATP and EC were decreased, respectively, to 20 and 40% of the control. These decreases were not as great with longer anaerobic treatments, and there was no change in the content of total adenosine phosphates. Oxygen enrichment (40%) stimulated the activity of nitrogenase by 2.5 fold in four minutes with a concomitant increase of ATP and EC by 40% and 14%, respectively, and an exhaustion of AMP. Longer treatments of oxygen enrichment lessened the initial effects. These findings indicate that ATP and energy charge probably regulate the activity of nitrogenase and an active adenylate kinase must be operating in the nodules to maintain an energy supply for the basal metabolism and for the nitrogenase under temporary stressed conditions. |
| |
Keywords: | |
本文献已被 ScienceDirect 等数据库收录! |
|