BIOT 20 |
| The driving forces that contribute to protein folding in the cell are extremely important to understand the biology of living organisms. Yet, these key forces and the related underlying mechanisms are still poorly understood. The physical interactions responsible for conformational sampling in the cell start acting cotranslationally during ribosome-assisted protein biosynthesis, in the absence of any denaturing agents and under physiologically relevant temperature and solution conditions. We have investigated the conformation of a series of N-terminal protein fragments of increasing length on the ribosome by dynamic fluorescence depolarization and cone angle analysis. Sequences belonging to proteins capable of independent folding and intrinsically unstructured proteins were analyzed. Nascent polypeptide dynamics in the low ns and sub-ns timescale regimes have been identified at specific chain lengths, showing how independent structure and motions evolve at different stages of chain elongation on the ribosome. In addition, computational approaches have been adopted as a complementary tool, to gather information of general applicability on the role of both short-/long-range interactions and nonpolar surface burial for the formation of native-like structure as a function of chain elongation (from N- to C- terminus). |
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Biophysical and Biomolecular Symposium: Protein Folding & Characterization
8:00 AM-11:10 AM, Sunday, August 19, 2007 BCEC -- 106, Oral
Division of Biochemical Technology |