title: [Photochemical and spectral properies of the photosystem I reaction centers-enriched particles].
abstract: The photosystem I reaction centers-enriched particles (RCP) having the ratio of P700/chlorophyll of 1 : 20--1 :30 were prepared from stroma lamellae photosystem subchloroplast fragments by extraction with water-saturated ether. The EPR signals and light-induced absorption changes indicate that the reaction centers are active in the particles. The spectral properties of the RCP were characterized. The main red absorption maximum is located at 673--674 nm with a "shoulder" at about 684--688 nm. A comparative analysis of the subchloroplast fragments and RCP absorption and fluorescence spectra suggests that the chl. a forms absorbed in the region of 680--695 nm are more closely associated with the reaction center. The most long-wavelength absorbing chl. a forms with maxima around 730--740 nm in the low temperature fluorescence spectra were not found in the RCP.
mesh_terms: D002736:Chloroplasts / Q000378:metabolism*; D004578:Electron Spin Resonance Spectroscopy; D008027:Light; D010788:Photosynthesis; D010944:Plants; D013050:Spectrometry, Fluorescence; D013053:Spectrophotometry
vernacular_title: Fotokhimicheskie i spektral'nye svoĭstva chastits, obogashchennykh reaktsionnymi tsentrami fotosistemy I.