General information
Organisation
The French Alternative Energies and Atomic Energy Commission (CEA) is a key player in research, development and innovation in four main areas :
• defence and security,
• nuclear energy (fission and fusion),
• technological research for industry,
• fundamental research in the physical sciences and life sciences.
Drawing on its widely acknowledged expertise, and thanks to its 16000 technicians, engineers, researchers and staff, the CEA actively participates in collaborative projects with a large number of academic and industrial partners.
The CEA is established in ten centers spread throughout France
Reference
SL-DRF-24-0773
Direction
DRF
Thesis topic details
Category
Life Sciences
Thesis topics
Role of excited state vibrational modes of chlorophylls in photosynthesis
Contract
Thèse
Job description
Photosynthesis empowers the entire biosphere and is arguably the most important biological process on earth. The quantum efficiency of excitation energy transfer (EET) in photosynthetic light-harvesting complexes can reach almost unity. This high efficiency is even more puzzling if we take into account that the high excitation energy transfer through hundreds of pigments in a disordered energetic landscape cannot be explained with the current models. Currently, there are two main hypotheses to explain the ultrafast energy transfer: “quantumness” and “vibrational assistance” (see context section). To validate these hypotheses, it is necessary to characterize the electronic and vibrational properties of the excited states of the cofactors involved in the ETT process. We have designed an interdisciplinary project, in which the student will be trained in biochemical techniques for protein purification and ultrafast photophysics techniques to analisys of the excitation energy transfer. The use of different detergents for purifying light-harvesting complexes leads to disturbed systems with differences in the excitation energy pathways. The differences between light-harvesting complexes from each purification will be characterized by resonance Raman and time-resolved fluorescence. Then, we will use ultrafast techniques such as fs-transient absorption, 2-D electronic spectroscopy (2DES) and femtosecond stimulated Raman Spectroscopy (FSRS). This data will be employed to develop new models for photosynthetic energy transfer. The student will be involved in the analysis and discussions for the theoretical modeling of this process but learning modeling techniques is out of the scope of the thesis.
University / doctoral school
Sciences Chimiques: Molécules, Matériaux, Instrumentation et Biosystèmes (2MIB)
Paris-Saclay
Thesis topic location
Site
Saclay
Requester
Position start date
01/10/2024
Person to be contacted by the applicant
LLANSOLA-PORTOLES Manuel manuel.llansola@i2bc.paris-saclay.fr
CNRS
DRF/JOLIOT/SB2SM
0033-169082496
Tutor / Responsible thesis director
LLANSOLA-PORTOLES Manuel manuel.llansola@i2bc.paris-saclay.fr
CNRS
DRF/JOLIOT/SB2SM
0033-169082496
En savoir plus
https://joliot.cea.fr/drf/joliot/Pages/Entites_de_recherche/I2BC_saclay/SB2SM/lbms.aspx