FLUCTUATION OF ENZYME ACTIVITIES RELATED TO NITROGEN FIXATION, C6/Cl RATIO, AND NICOTINAMIDE NUCLEOTIDE CONTENTS DURING SOYBEAN PLANT DEVELOPMENT

概要

論文の詳細を見る
Activities of enzymes related to nitrogen assimilation, hexose metabolism, C6/C1 ratios and nicotinamide adenine nucleotide content were determined in soybean nodules and root tissues during the plant development. Glutamate dehydrogenase and alanine dehydrogenase activities in nodules were more dependent on NADH than NADPH, though the NADPH-dependent activities exhibited higher values in the roots. In both tissues GOGAT activity was NADH-dependent, and G6P dehydrogenase and 6PG dehydrogenase activities were NADP-dependent. These enzyme activities on a mg protein basis showed high levels throughout the plant development and their fluctuations were not correlated with those of nitrogenase activity. Their specific activities, however, exhibited higher values at the early stage of plant development. The C6/C1 ratios in nodule and root tissues were always below 0.6. The value was 0.5 at the early stage, then decreased gradually and increased after the flowering stage. At the early pod filling stage the nodules showed the lowest value, approximately 0.3. The low C6/C1 ratio and high 6PG dehydrogenase activity suggested the contribution of the pentose phosphate pathway. Nicotinamide adenine nucleotide contents increased in parallel with the increase of nitrogenase activity as expressed on a nodule fresh weight basis. At the flowering stage the coenzyme contents were maximum, and accumulation of NADH and NADPH, which are considered to contribute to the reducing power for nitrogen fixation and ammonia assimilation, occurred in the nodules along with nitrogen fixation.
社団法人日本土壌肥料学会の論文

FLUCTUATION OF ENZYME ACTIVITIES RELATED TO NITROGEN FIXATION, C6/Cl RATIO, AND NICOTINAMIDE NUCLEOTIDE CONTENTS DURING SOYBEAN PLANT DEVELOPMENT

スポンサーリンク

概要

著者

関連論文

スポンサーリンク