Thesis presented in 2006

Abstract:
In the space of one decade, DNA-chips became tools which cannot be ignored in the present scientific context. Placed at the interface between traditional disciplines, they are currently used for gene expression studies, SNP detection or who le genome analysis. This work uses for the first time surface plasmon resonance imaging coupled with temperature control - from 20°C to 80°C - applied to DNA-chip studies. Ln the first part, we study the DNA hybridization process on a solid support from a both kinetic and thermodynamic point of view, assuming the theoretical Langmuir model, ΔH and ΔS parameters are estimated as a function of probes length and show a non-conventional behavior compared to the theoretical prediction. We assume that it could be due to a lack of accessibility on the DNA-chip surface. The second part is dedicated to point mutation detection using temperature scan technique. Our results, obtained with two models (K-ras and Cycline D1), are in good agreement with theoretical predictions in solution and let assume that this method could be applied for SNPs (Single Nucleotide Polymorphism) detection on biological samples. A last application concerns the DNAglycosylase Fpg interactions with damaged DNA duplexes. Two lesions, 8-oxo-guanine and 5',8Cyclo-2'-desoxyadenosine, are used and Fpg enzymatic activity is only detected for the first one using an original thermal method.

Keywords:
SPRi, DNA Fusion Curves, Pyrrole Electropolymerization, Langmuir Model, DNA-Glycosylase Fpg, DNA Filters