Open AccessBacteriochlorophyll interaction with singlet oxygen in membranes of purple photosynthetic bacteria: does the protective function of carotenoids exist?
Author(s) -
З. К. Махнева,
А. А. Ашихмин,
М. А. Bolshakov,
А. А. Москаленко
Publication year - 2019
Publication title -
doklady akademii nauk. rossijskaâ akademiâ nauk
Language(s) - English
Resource type - Journals
ISSN - 0869-5652
DOI - 10.31857/s0869-56524864504-508
Subject(s) - bacteriochlorophyll , singlet oxygen , carotenoid , photochemistry , green sulfur bacteria , chemistry , purple bacteria , photosynthesis , singlet state , membrane , sulfur , monomer , oxygen , biophysics , biochemistry , biology , photosynthetic reaction centre , physics , organic chemistry , excited state , nuclear physics , polymer
The direct action of singlet oxygen on the bacteriochlorophyll (BChl) of light-harvesting complexes in the membranes of four types of purple non-sulfur and sulfur photosynthesizing bacteria with and without carotenoids has been studied. It has been found that BChl in carotenoid-less samples is generally more resistant to the action of singlet oxygen compared to the control. It is assumed that carotenoids are not needed to protect BChl of bacterial light-harvesting complexes from singlet oxygen, and in the classic work of Griffith et al. [1] the apoptosis process in carotenoid-less mutant cells, which involves the destruction of complexes, the appearance of monomeric BChl and generation of singlet oxygencaused by BChl, followed by BChl oxidation, was mistakenly attributed to the protective function of carotenoids.