Adenylate ratios in the cytosol, chloroplasts and mitochondria of barley leaf protoplasts during photosynthesis at different carbon dioxide concentrations

[摘要]

Barley (Hordeum vulgare) protoplasts were incubated in darkness and in the light at saturating and limiting CO₂ concentrations. The protoplasts were fractioned by a membrane filtration technique which allows quenching of the metabolism by acidification within about 0.1 s and the ATP/ADP ratios in the cytasol, chloroplasts and mitochondria were determined. It is concluded that the cytosolic ATP/ADP ratio is considerably higher during photosynthesis at limiting CO₂ (which is the normal situation for a C₃ plant in air) compared to photosynthesis at saturating CO₂ or darkness.

[学科分类] 生物化学/生物物理

[关键词] ATP/ADP ratio;Chloroplast;Cytosol;Mitochondria;Protoplast;NADP-TPD;NADP-triosephosphate dehydrogenase;PEP;phosphoenolpyruvate