Protein-Protein Interactions in Multi-Enzyme Complex

Protein-Protein Interactions in Multi-Enzyme Complex 

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- Date/Time : Wed June 11., 2003


         PM 16:15 

- Speaker : 정효일 박사


           - Department of Biochemistry


           - Univ. of Cambridge, UK

- Place : Life Science Bldg. #104

- For inquires : Professor Kwan Yong Choi Dept. of Life Science


            생명과학과 최관용 교수 (☎279-2295)

- Support : 단백질 폴딩제어연구실 (NRL)

Abstract -


    The study of how biological molecules interact with one another is central to an understanding of the chemistry of life. A number of questions have to be addressed in these studies: How strong the interactions? What defines the specificity of the interactions? Finally, what kind of interacting molecules can be used for the biomedical applications?


The formation of the pyruvate dehydrogenase multi-enzyme complex is an example of the self-assemblies that include protein folding and the tobacco mosaic virus. This complex is relatively simple to study and has been regarded as one of the well-known nanomachines in biological system. In the first talk, I will present the biophysical/chemical properties of protein-protein interactions in the assembly of the pyruvate dehydrogenase analysed by Surface Plasmon Resonance (SPR) detection and Isothermal Microcalorimetry (ITC). The discrepancy between the conventional and modern thermodynamic interpretation is well emphasised in terms of structure-based thermodynamics. Alanine-scanning mutagenesis unravels key residues involved in the binding hot spot. Furthermore, Cysteine engineering technique systematically dissects the role of charged group and aliphatic chain length of Arginine residue in the binding interface.


  In the second talk, I will highlight the biomedical application such as Molecular Imaging by using the knowledge of the biomolecular interactions. Monitoring the modern therapies requires the visualisation of the drug target and imaging the drug-target interactions in live animals and ultimately, in patients. To pursue this purpose, identification and validation of high-affinity probes against the target molecules in living systems is one of the key prerequisites. This can be accomplished by SPR and ITC analysis, which are the fundamental methodologies of proteomics.