Evidence for a dual role of cytochrome c-553 and plastocyanin in photosynthesis and respiration of the cyanobacterium,Anabaena variabilis |
| |
Authors: | Wolfgang Lockau |
| |
Affiliation: | (1) Institut für Botanik, Universität Regensburg, Universitätsstraße 31, D-8400 Regensburg, Federal Republic of Germany |
| |
Abstract: | The cytochrome oxidase activity (oxygen uptake in the dark) of a membrane preparation from Anabaena variabilis was found to be stimulated by cytochrome c-553 and plastocyanin obtained from this alga. Cytochrome c from horse heart was as active as cytochrome c-553, whereas little or no stimulation of oxygen uptake was obtained with cytochromes c2 from two Rhodospirillaceae, the plastidic cytochrome c-552 from Euglena, and plastocyanin from spinach. Cytochrome c-553 (A. variabilis) stimulated photosystem 1 activity in the same preparation much more than cytochrome c (horse heart). The results indicate that cytochrome c-553 and plastocyanin, besides their established function as electron donors of photosystem 1, participate in respiratory electron transport as reductants of a terminal oxidase. Photooxidation and dark oxidation show a different donor specificity.Abbreviations Chl chlorophyll a - TMPD N,N,N,N-tetramethyl-p-phenylenediamine |
| |
Keywords: | Cyanobacteria Anabaena variabilis Electron flow Photosynthesis Respiration Cytochrome oxidase Cytochrome c-553 Plastocyanin |
本文献已被 SpringerLink 等数据库收录! |
|