Missions

The molecular mechanism of bio-magnetic sensing, utilized for navigation by migrating animals, is a major unsolved problem in contemporary science. Despite over 50 years of research into magneto-reception in animals, scientists have thus far been unable to decipher the molecular mechanism for magneto-sensing.
In their recently funded HFSP project, our partners M. Kosloff (U Tel-Aviv, Isreal) and I. Schapiro (U Dortmund, Germany) make the hypothesis that opsin, the biological light-sensitive pigment, is the actual magneto-receptor. Visual opsins, also named rhodopsins, are transmembrane proteins arranged in membrane stacks within photoreceptor cells in the eye that transmit visual signals to the brain. Opsins covalently bind a retinal chromophore via a Schiff base bond, making these proteins light-sensitive. These specific “UV-opsins” contain a deprotonated retinal Schiff base as a chromophore, which absorbs light in the ultraviolet (UV) spectral range.

Within this context, we propose to revisit the photo-physics of neutral retinal Schiff bases in solution, in order to decipher spectroscopic signatures, emission or absorption, of possible triplet states.
Ultrafast spectroscopy is the tool of choice for studies, but has not been applied with sufficient temporal resolution and spectral coverage on neutral retinal Schiff bases in the past.

Activities

The post-doc researcher will conduct femtosecond spectroscopy experiments, transient absorption as well as fluorescence, in the UV and visible spectral ranges on all-trans retinal Schiff bases in different solvents and, if possible, as a function of temperature.
He or she will be in charge of co-supervising a master student working on the same subject. A contribution to tutored projects for master's and bachelor students, to the proper organization and development of our ultra-fast spectroscopy facilities, as well as to fundraising is expected.

Skills

The candidates must hold a doctorate in Physics or Physical Chemistry. This position requires a solid background in ultrafast molecular spectroscopy and nonlinear optics, and is a must for recruitement. Additional qualifications such as training and supervision of master students, and proficiency in Python and/or Matlab are valuable assets.

Work Context

At the Institute of Physics and Chemistry of Materials in Strasbourg, our research team studies retinal proteins since more than twenty years by ultrafast spectroscopy. Within the latest ANR project UltrArchae, a PhD project was entirely devoted to the experimental investigation of the excited state properties of Archaerhodopsin-3 and its fluorescent mutants.

The IPCMS is an interdisciplinary laboratory for physics and chemistry with a total staff of 230 people. Located on the Cronenbourg campus, it is easily accessible by public transport and bicycle, only 20 minutes away from the historic city center of Strasbourg.
BIODYN (“Biophysics and Dynamics of Organic Nanostructures”) is a research team led by A. Boyer, J. Léonard and S. Haacke (https://www.ipcms.fr/en/equipe/biodyn/).

The position is located in a sector under the protection of scientific and technical potential (PPST), and therefore requires, in accordance with the regulations, that your arrival is authorized by the competent authority of the MESR.

Constraints and risks

Laser safety
Minor chemical hazards (solvent handling)