Current Issue      Archive      Editorial Board      Online Submission    

Jointly Published by

 Institute of Botany, CAS


Botanical Society of China

The Relationships between Nitrogen Fixation and Several Kinds of Energy Metabolism by Gloeocapsa sp
Journal of Integrative Plant Biology 30(3).
 
Wang Cheng-yi and Wang Fa-zhu

Gloeocapsa sp., a species of anicellular blue-green alga, fixes dinitrogen mostly under light. The energy (ATP and reductant) needed for nitrogen fixation may be provided by photoreaction and aerobic catabolism. The nitrogenase activity (acetylene reduction) in vivo was decreased under the conditions of dark and inhibition of photo-phosphorylation or oxidative phosphorylation in the light. When photosystem ¢ò was inhibited by the presence of DCMU, nitrogenase activities in both reactions of acetylene reduction and hydrogen evolution may be muchenhanced probably due to eliminating of the damage caused by the oxygen produced in the photolysis of water. The effects of the oxygen present in the atmosphere of the reaction systemand produced by the cells are different. It is shown that some trace oxygen seems to be required for nitrogen fixation by the energy supply of aerobic actabolism and oxidative phosphorylation. While the fixation of dinitrogen was inhibited by CO or no any reducible substrate was present, 70-100% of the energy accepted by nitrogenase was evolved as hydrogen. The algal cells also showed hydrogen uptake reaction, but no enhancement of nitrogen fixation by the hydrogen uptake was found.


Keywords:Gloeocapsa sp.; Nitrogen fixation; Energy metabolism



  
Editorial Office, Journal of Integrative Plant Biology, Institute of Botany, CAS
No.20 Nanxincun, Xiangshan, Beijing 100093, China
 Tel: +86 10 6283 6133     Fax: +86 10 8259 2636
E-mail: jipb@ibcas.ac.cn

nhl jerseys ÃÀŮͼƬ louis vuitton Jordan shoes Cheap Christian Louboutin chi flat iron louis vuitton dresses