Some physical approaches to protein folding

URL: http://www-spht.cea.fr/articles/T93/023 (sur invitation). AbstractInternational audienceProteins are weakly branched polymers built out of 20 species of monomers (aminoacids). They undergo a phase transition from a high temperature coil phase to a low temperature compact native state. This folded state has a unique structure, closely related to the biological activity of the protein. We present simple statistical mechanics models for the folding transition. These models are inspired from spin-glass theory, and display several aspects characteristic of the folding transition, such as the unicity of the folded state, large number of metastable states, high barriers, etc... In addition, in the folded state, short range structure (known as secondary structure) settles in. We propose simple models, based on Hamiltonian walks, for the formation and stability of secondary structures