Dr Hassan Abdoul-Carime


Employed as a Post Doc. Free University Berlin, Germany (FUB)
Start Date: November 2003, End Date: August/September 2004

I graduated from Paris-Nord University (France) in 1996 where I have been investigating electron transfer occurring during collision between a highly excited atoms (i.e., Rydberg atoms) and polar molecules and molecular clusters. It was during my Ph.D. times that I have had my first experience with the interaction of electrons with biologically relevant molecules. Indeed, I have performed the first measurements of electron attachment to nucleobases in the gas phase. After being graduated, I have had a one year contract as lecturer at the same University, continuing my Ph.D. work. Then, I went to Japan (Tsukuba) as a post-doctoral fellow to work on a different field: solution chemistry. However, I have been involved in the development of a home-built experimental apparatus to put large molecules in vacuum (electrospray – coupled to mass spectrometry technique). After my Japanese experience, I went back to the electron-molecule interaction problems at Prof. L. Sanche group (Canada) for more than 3 years, as a post-doctoral fellow. I have started investigation on how low energy electron can damage at the molecular level biological molecules (short strand DNA, DNA bases and amino acids) in condensed phase. I also have explored how low-energy electrons can induce radio-sensitization in nucleic acids containing halogenated–modified nucleobases. My background is nevertheless not restricted to biological molecules, also they represent the main part of my work since 1998. Indeed, I have had some contribution on potential sulfur contained atmospheric pollutants.Then I have taken a one year and half sabbatical to perform a real biological experiment (her name is Adele).

By 2002, Prof. Illenberger proposed me to join his group to work on biologically relevant molecules in the gas phase and cluster, under the contract with the EPIC network. At the beginning, I have planned to perform some measurements on amino-acids (cystein, tryptophan, proline) and proteins (N-acetyl-tryptophan). Those points are completed by now. In the gas phase, probing biologically relevant molecules were restricted to isolated nucleobases. I have shown for instance that electrons with energies below 3 eV can induce a loss of hydrogen at the specific nitrogen sites of DNA bases. In fact within DNA, nucleobases are bound to sugar molecules, via a chemical bond at one of the nitrogen sites. Therefore, I have suggested and then investigated how interaction of low electrons can be modified when the DNA bases (thymidine, bromouridine) are bound to sugar molecules which represent more closely DNA sub-units. I appreciate Prof. Illenberger to let me free for doing any experiments that I wanted to do, this way of our collaboration appears to be quite fruitful. I also have the opportunity to supervise (although not officially) the Ph.D. work of Sascha Golke.