In the unicellular green alga Chlorogonium elongatum, the synthesis of the plastid enzyme ribulose bisphosphate carboxylase/oxygenase (RuBPCase) and its mRNAs is under the control of light and acetate. Acetate is the sole metabolizable organic carbon source for this organism. Light greatly promotes
The effects of light quality and intensity on the synthesis of ribulose-1,5-bisphosphate carboxylase and its mRNAs in the green algaChlorogonium elongatum
β Scribed by E. Roscher; K. Zetsche
- Publisher
- Springer-Verlag
- Year
- 1986
- Tongue
- English
- Weight
- 438 KB
- Volume
- 167
- Category
- Article
- ISSN
- 0032-0935
No coin nor oath required. For personal study only.
β¦ Synopsis
In the green alga Chlorogonium elongarum the promoting effect of light on the synthesis of ribulose bisphosphate carboxylase/oxygenase (RuBPCase) is mainly caused by blue light of wavelengths between 430 nm and 510 nm, with a maximum effect at about 460 nm. Blue light also causes an increase in the amounts of the mRNAs for the large and the small subunits of the enzyme. Furthermore, the concentration of RuBPCase is affected by the light energy fluence rate. The rate of synthesis as well as the maximal obtainable concentration of the enzyme are functions of the light energy fluence rate up to 26 W.m-2. No further increase occurs beyond that intensity. The quantity of irradiation also alters the concentrations of the subunit mRNAs. The results indicate that the changes in the mRNA levels are the major regulatory steps in the light-dependent synthesis of the RuBPCase enzyme.
π SIMILAR VOLUMES
Photosynthetic electron transport capacity was varied in vivo in sugar beets using iron deficiency, and its effects on the light modulation of ribulose bisphosphate carboxylase (RuBPCase) studied. Three treatment groups corresponding to decreasing amounts of thylakoids per leaf area were examined: i