Influence of pH upon the Warburg Effect in Isolated Intact Spinach Chloroplasts: I. Carbon Dioxide Photoassimilation and Glycolate Synthesis 1
AUTOR(ES)
Robinson, J. Michael
RESUMO
The influence of pH upon the O2 inhibition of 14CO2 photoassimilation (Warburg effect) was examined in intact spinach (Spinacia oleracea) chloroplasts. With conditions which favored the Warburg effect, i.e. rate-limiting CO2 and 100% O2, O2 inhibition was greater at pH 8.4 to 8.5 than at pH 7.5 to 7.8. At pH 8.5, as compared with 7.8, there was an enhanced 14C-labeling of glycolate, and a decrease of isotope in some phosphorylated Calvin cycle intermediates, particularly triose-phosphate. The 14C-labeling of starch was also more inhibited by O2 at higher pH. The enhanced synthesis of glycolate during 14CO2 assimilation at higher pH resulted in a diminution in the level of phosphorylated intermediates of the Calvin cycle, and this was apparently a causal factor of the increased severity of the Warburg effect.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=542442Documentos Relacionados
- Influence of pH upon the Warburg Effect in Isolated Intact Spinach Chloroplasts: II. Interdependency of Glycolate Synthesis upon pH and Calvin Cycle Intermediate Concentration in the Absence of Carbon Dioxide Photoassimilation 1
- Influence of Hydrogen Peroxide upon Carbon Dioxide Photoassimilation in the Spinach Chloroplast: I. HYDROGEN PEROXIDE GENERATED BY BROKEN CHLOROPLASTS IN AN “INTACT” CHLOROPLAST PREPARATION IS A CAUSAL AGENT OF THE WARBURG EFFECT 12
- Photosynthetic Intermediates, The Warburg Effect, and Glycolate Synthesis in Isolated Spinach Chloroplasts 1
- Regulation of Photosynthetic Electron Transport in Intact Spinach Chloroplasts: I. INFLUENCE OF EXOGENOUS SALTS ON OXALOACETATE REDUCTION 12
- Glycolate Formation in Intact Spinach Chloroplasts 1