Limited photosynthetic electron flow but no CO2 fixation in Chlamydomonas mutants lacking photosystem I

FEBS Letters

Cournac, Laurent²  Peltier, Gilles²  Bennoun, Pierre³  Redding, Kevin¹ 

[1] University of Geneva, Departments of Molecular Biology and Plant Biology, 30, quai Ernest-Ansermet, CH-1211 Geneva 4, Switzerland;CEA Cadarache, Laboratoire d'Ecophysiologie de la Photosynthèse, Département d'Ecophysiologie Végétale et de Microbiologie, F-13108 Saint-Paul-lez-Durance, France;Institut de Biologie Physico-Chimique, Centre National de la Recherche Scientifique, UPR 9072, 13, rue Pierre et Marie Curie, F-75005 Paris, France

关键词: Chlamydomonas;    Photosystem I;    Photosystem II;    Gene deletion;    O2 exchange;    CO2 exchange;   

DOI  :  10.1016/S0014-5793(97)01170-8

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

By measuring O₂ and CO₂ exchange in mutants of the green alga Chlamydomonas reinhardtii in which genes encoding the reaction center of photosystem I (psaA or psaB) have been deleted, we found that a photosystem II-dependent electron flow using O₂ as the final acceptor can be sustained in the light. However, in contrast with recent reports using other Chlamydomonas mutants (B4 and F8), we show here that CO₂ fixation does not occur in the absence of photosystem I. By deleting the psaA gene in both B4 and F8 strains, we conclude that the ability of these mutants to fix CO₂ in the light is due to the presence of residual amounts of photosystem I.

【 授权许可】

Unknown