Glycinebetaine protects the D1/D2/Cytb559 complex of photosystem II against photo-induced and heat-induced inactivation.
The presence of 1.0 mol/L glycinebetaine during isolation of D1/D2/Cytb559 reaction centre (RC) complexes from photosystem II (PSII) membrane fragments preserved the photochemical activity, monitored as the light-induced reduction of pheophytin and electron transport from diphenylcarbazide to 2.6-dichlorophenol-indophenol.-Glycinebetaine also protected the D1/D2/Cytb559 complexes against strong light-induced damage to the photochemical reactions and the irreversible bleaching of beta-carotene and chlorophyll. The presence of glycinebetaine also enhanced thermotolerance of the D1/D2/Cytb559 complexes isolated in the presence of 1.0 mol/L betaine with an increase in the temperature for 50% inactivation from 29 degrees C to 35 degrees C. The results indicate an increased supramolecular structural stability in the presence of glycinebetaine.
Allakhverdiev
Suleyman I
SI
Department of Regulation Biology, National Institute for Basic Biology, Okazaki 444-8585, Japan.
Hayashi
Hidenori
H
Nishiyama
Yoshitaka
Y
Ivanov
Alexander G
AG
Aliev
Jalal A
JA
Klimov
Vyacheslav V
VV
Murata
Norio
N
Carpentier
Robert
R
D015086:2,6-Dichloroindophenol / Q000378:metabolism; D001622:Betaine / Q000494:pharmacology*; D002734:Chlorophyll / Q000378:metabolism; D003573:Cytochrome b Group / Q000187:drug effects / Q000378:metabolism* / Q000528:radiation effects; D004160:Diphenylcarbazide / Q000378:metabolism; D004579:Electron Transport; D006358:Hot Temperature; D045342:Light-Harvesting Protein Complexes; D010084:Oxidation-Reduction; D010674:Pheophytins / Q000378:metabolism; D038761:Photobleaching; D010777:Photochemistry; D045322:Photosynthetic Reaction Center Complex Proteins / Q000037:antagonists & inhibitors / Q000187:drug effects / Q000378:metabolism* / Q000528:radiation effects; D045332:Photosystem II Protein Complex; D011809:Quinones / Q000378:metabolism; D018724:Spinacia oleracea / Q000187:drug effects / Q000378:metabolism / Q000528:radiation effects; D019207:beta Carotene / Q000378:metabolism
D003573:Cytochrome b Group; D045342:Light-Harvesting Protein Complexes; D010674:Pheophytins; D045322:Photosynthetic Reaction Center Complex Proteins; D045332:Photosystem II Protein Complex; D011809:Quinones; D019207:beta Carotene; D002734:Chlorophyll; D004160:Diphenylcarbazide; D001622:Betaine; C019313:cytochrome b559; D015086:2,6-Dichloroindophenol