title: Novel mechanism for temperature-independent transitions in flexible molecules: role of thermodynamic fluctuations.
abstract: A novel physical mechanism is proposed to explain the temperature-independent transition reactions in molecular systems. The mechanism becomes effective in the case of conformation transitions between quasi-isoenergetic molecular states. It is shown that at room temperatures, stochastic broadening of molecular energy levels predominates the energy of low-frequency vibrations accompanying the transition. This leads to a cancellation of temperature dependence in the stochastically averaged rate constants. As an example, a physical interpretation of temperature-independent onset of P2X{3} receptor desensitization in neuronal membranes is provided.
authors.affiliation: Bogolyubov Institute for Theoretical Physics, National Academy of Science of Ukraine, 14-b Metrologichna Street, 03680 Kyiv, Ukraine.
authors.forename: V I
authors.initials: VI
authors.lastname: Teslenko
authors.forename: E G
authors.initials: EG
authors.lastname: Petrov
authors.forename: A
authors.initials: A
authors.lastname: Verkhratsky
authors.forename: O A
authors.initials: OA
authors.lastname: Krishtal
mesh_terms: D002462:Cell Membrane / Q000737:chemistry / Q000378:metabolism; D008954:Models, Biological; D009474:Neurons / Q000737:chemistry / Q000378:metabolism; D018048:Receptors, Purinergic P2 / Q000737:chemistry / Q000378:metabolism; D058476:Receptors, Purinergic P2X2; D013269:Stochastic Processes; D013816:Thermodynamics; D013997:Time Factors; D044366:Transition Temperature
chemical_list: D018048:Receptors, Purinergic P2; D058476:Receptors, Purinergic P2X2