Immobilized proteins in porous materials –Structural studies by Pulse EPR dipolar spectroscopY (iSPY).

Nature is by far the most versatile chemist and modern research efforts have harnessed the power of Nature by usingbiomolecules such as proteins as building blocks or targets for various technological applications. In many cases theimmobilization of a protein in a synthetic matrix is essential. In particular protein-porous material hybrids have received muchattention but their preparation have been non-trivial, often limited by the size compatibility between the pore and the proteinand the surface properties. The quest for a suitable protein-matrix combination not only requires extensive syntheticoptimization, but also the development of appropriate methodologies that can be used to determine the effect of the matrixon the structure and stability of the protein. In this multidisciplinary action, the stabilities, structures and dynamics of hemeproteins (globins) immobilized in mesoporous silica or titania will be studied by EPR. This class of hybrid materials arethemselves also of great interest because of potential electrochemical biosensing and biocatalysis applications. Novelorthogonally spin-labeled globins will be prepared and incorporated into (modified) mesoporous silica and titania. Pulsedipolar spectroscopy will be used to measure nanometric distance constraints within the free and immobilized globins.Combined with computational models, these measurements will provide unique insights into effects of incorporation on thetertiary structures and conformational flexibilities of the proteins. This study will not only result in the development of ageneric analytical toolbox, based on spin-label EPR, for the characterization of proteins immobilized in matrices, but alsolead to advances in the understanding and preparation of protein-porous material hybrids.

Keywords:BIOSENSORS, SPECTROSCOPY

Disciplines:Classical physics, Elementary particle and high energy physics, Other physical sciences