Project description:Study of the photosynthetic metabolism of purple sulphur bacteria Halorhodospira halophila by analysing the proteome of the bacteria cultivated with various sulphur compounds. In this way for the first time a comprehensive sulphur-oxidative photosynthetic network of an Halorhodospiraceaen is presented. As some Ectothiorhodospiraceae have been shown to use arsenite as photosynthetic electron donor, We performed a mass spectrometry-based whole proteome analysis with label-free quantification of H. halophila photoheterotrophically grown in the presence of various inorganic reduced sulphur compounds and in the concomitant presence of sulphide and arsenite, in order to identify proteins (enzymes and electron carriers) involved in its photosynthetic metabolism. Quantitative proteomics revealed that the SoxAXYZB system, typically dedicated to thiosulphate oxidation, is overproduced in this latter growth condition as are two electron carriers, the cytochrome c551/c5 and PioC/HiPIP III. Taken together, these results argue in favour of a chemically-formed thioarsenate oxidized by the Sox system, with c551/c5 and PioC/HiPIP III funnelling electrons towards the Reaction Centre.
Project description:Suitability of CATMA for the analysis of the transcriptome of Thellungiella halophila - flower/leaf transcriptomic comparison in Arabidopsis and Thellungiella. adt09-01_thellungiella - thelungiella
