title: [Magnetic relaxation of water protons and the state of the water photodissociation system in chloroplasts].
abstract: The spin-spin relaxation time T2 of water protons is measured in chloroplast suspensions. It is shown that chloroplast lamellae efficiently increase the rate of proton magnetic relaxation, this effect being a linear function of chloroplast concentration. There is a fast exchange between the water molecules in different environments, thus the measured relaxation rate is a weight average of all water molecules. The rate of proton relaxation is decreased when membrane bound manganese is removed from chloroplasts by tris-washing procedure. The relaxation effect is slightly reduced in the presence of Photosystem II electron acceptors.
mesh_terms: D015086:2,6-Dichloroindophenol; D002736:Chloroplasts / Q000378:metabolism; D005292:Ferricyanides; D009682:Magnetic Resonance Spectroscopy; D008345:Manganese / Q000378:metabolism; D011188:Potassium; D011522:Protons; D014867:Water
chemical_list: D005292:Ferricyanides; D011522:Protons; D014867:Water; D008345:Manganese; D015086:2,6-Dichloroindophenol; D011188:Potassium
vernacular_title: Magnitnaia relaksatsiia protonov vody i sostoianie sistemy fotorazlozheniia vody v khloroplastakh.