Singlet oxygen inhibits ATPase and proton translocation activity of the thylakoid ATP synthase CF1CFo.
Singlet oxygen ((1)O(2)) produced in plants during photosynthesis has a strong damaging effect not only on both photosystems but also on the whole photosynthetic machinery. This is also applicable for the adenosine triphosphate (ATP) synthase. Here we describe the impact of (1)O(2) generated by the photosensitizer Rose Bengal on the ATP hydrolysis and ATP-driven proton translocation activity of CF1CFo. Both activities were reduced dramatically within 1min of exposure. Interestingly, it is shown that oxidized thylakoid ATP synthase is more susceptible to (1)O(2) than CF1CFo in its reduced state, a new insight on the mechanism of (1)O(2) interaction with the gamma subunit.
Buchert
Felix
F
Pflanzenphysiologie, Justus-Liebig Universität, Zeughaus, Giessen, Germany.
Forreiter
Christoph
C
D000255:Adenosine Triphosphate / Q000378:metabolism; D002462:Cell Membrane / Q000201:enzymology; D025222:Chloroplast Proton-Translocating ATPases / Q000037:antagonists & inhibitors* / Q000378:metabolism; D003545:Cysteine / Q000378:metabolism; D006868:Hydrolysis; D008274:Magnesium / Q000378:metabolism; D010084:Oxidation-Reduction; D011522:Protons; D012395:Rose Bengal / Q000494:pharmacology; D026082:Singlet Oxygen / Q000378:metabolism*; D018724:Spinacia oleracea / Q000201:enzymology; D020524:Thylakoids / Q000201:enzymology*
D011522:Protons; D026082:Singlet Oxygen; D012395:Rose Bengal; D000255:Adenosine Triphosphate; D025222:Chloroplast Proton-Translocating ATPases; D008274:Magnesium; D003545:Cysteine