Coupling between transport phenomena and conformational transitions: Isothermal water transport and “asymmetric osmotic pressure” across a “membrane phase” promoted by a helix-coil transition

摘要: Abstract A membrane system is described consisting of an aqueous concentrated solution poly-L-lysine bounded by two rigid conventional membranes permeable to water and small ions but impervious the polymer. When a large steady pH difference maintained between external isoosmotic solutions α β, vertical volume flow may be observed from acid basic across membrane. The give rise pressure corresponding non-equilibrium state system. These effects, first reported Liquori et al. [1] are extensively analyzed thermodynamic point view. It shown that gradient maintains conformational which known undergo regulated helix-coil transition. latter in turn determines chemical potential within phase acting as main driving force flow. Using flux equations irreversible thermodynamics connection with model transition proposed author [3,4] compact derived for isobaric osmotic agreement experimental results. Possible implications this study active transport phenomena biological discussed.