Abstract:
Halorhodospira halophila is a strict anaerobe and obligate phototroph using sulfur compounds oxidation as electron donors to supply its anoxygenic photosynthesis. Very little information on its photosynthetic pathway is currently available. The previous works propose a metabolic network with a high degree of "redundancy", with multiple soluble electron carriers, multiple soluble and membranous enzymes, funnelling the central photosynthetic reaction Centre (RC) in electrons. One of the questions is therefore the respective role of the different electron carriers and enzymes. The previous works also suggest unusual properties, in H. halophila, for three enzymes: the RC, the Sulfur OXidation system SOX and the alternative arsenite oxidase Arx. The very low redox potential of the first one raises the question of its function, the possible role of the second one in oxidation of thioarsenate would make it unique while the inability of the third one to sustain photosynthetic growth under arsenite is questioning. The PhD project aims to address these points in a multidisciplinary approach combining biochemistry, molecular biology, and light induced/UV-Vis/EPR spectroscopies for both structural and functional studies.
Co-supervisors :
- Jean Alric (BIAM)
- Barbara Schoepp-Cothenet (BIP)
Credits: Emmauella Serwaa and Nil Gaudu