The kinetics of the flash-induced P515 response in relation to the H+-permeability of the membrane bound ATPase in spinach chloroplasts.
The effect of dicyclohexylcarbodiimide (DCCD) on the kinetics of the flash-induced P515 response and on the activity of the ATPase was investigated in isolated spinach chloroplasts. It was found that after the addition of 5 X 10(-8)mol DCCD the rate of ATP hydrolysis induced by a period of 60 sec illumination was decreased to less than 5% of its original value. At this concentration, hardly any effect, if at all, could be detected on the kinetics of the flash-induced P515 response, neither in dark-adapted nor in light-activated chloroplasts. It was concluded that the presence of concentrations of DCCD, sufficiently high to affect the ATPase activity, does not affect the kinetics of the flash-induced P515 response. Since DCCD decreases the H+ permeability of the membrane-bound ATPase, it was concluded that this permeability coefficient for protons is not an important factor in the regulation of the flash-induced membrane potential and, therefore, does not affect the kinetics of the flash-induced P515 response.
D000251:Adenosine Triphosphatases / Q000378:metabolism*; D002463:Cell Membrane Permeability / Q000187:drug effects*; D002734:Chlorophyll / Q000378:metabolism*; D002736:Chloroplasts / Q000201:enzymology* / Q000378:metabolism; D004024:Dicyclohexylcarbodiimide / Q000494:pharmacology; D007700:Kinetics; D008027:Light; D045342:Light-Harvesting Protein Complexes; D010788:Photosynthesis; D045322:Photosynthetic Reaction Center Complex Proteins; D010940:Plant Proteins / Q000378:metabolism*; D011522:Protons; D014675:Vegetables
D045342:Light-Harvesting Protein Complexes; D045322:Photosynthetic Reaction Center Complex Proteins; D010940:Plant Proteins; D011522:Protons; D002734:Chlorophyll; D004024:Dicyclohexylcarbodiimide; D000251:Adenosine Triphosphatases