title: Communication: Conformation state diagram of polypeptides: a chain length induced α-β transition.
abstract: By using a generic coarse grained polypeptide model, we perform multicanonical molecular dynamics simulations for determining the equilibrium conformation state diagram of a single homopolypeptide chain as a function of the chain length and temperature. The state diagram highlights the thermal regimes of stability for various conformational patterns in polypeptides, including swollen, random and collapsed coils, globular structures, extended and bended α helices, and compact β bundles. Remarkably, at low temperatures we observe a sharp transition from extended α helix to compact β bundles as the chain length increases. This finding indicates that the chain length is one of the intrisic factors that can trigger α-β transformations in a broad class of polypeptides.
authors.affiliation: Centre for Molecular Nanoscience, School of Chemistry, University of Leeds, LS2 9JT Leeds, United Kingdom.
authors.forename: Piero
authors.initials: P
authors.lastname: Ricchiuto
authors.forename: Andrey V
authors.initials: AV
authors.lastname: Brukhno
authors.forename: Emanuele
authors.initials: E
authors.lastname: Paci
authors.forename: Stefan
authors.initials: S
authors.lastname: Auer
mesh_terms: D008958:Models, Molecular; D056004:Molecular Dynamics Simulation; D010455:Peptides / Q000737:chemistry*; D044367:Phase Transition; D017433:Protein Structure, Secondary; D013696:Temperature
chemical_list: D010455:Peptides