Effects of pH on structural and functional properties of porin from the outer membrane of Yersinia pseudotuberculosis . II. Characterization of pH-induced conformational intermediates of yersinin

摘要: pH-Induced intermediates of Omp F-like porin from the outer membrane Yersinia pseudotuberculosis (yersinin) were characterized by fluorescence and fluorescent probe spectroscopy circular dichroism. The most dramatic changes in intrinsic protein induced pH titration correlated with different conformational states molecule. pH-induced transitions yersinin can be described terms a three-state model: (1) disordering associates formation trimers structurally similar to native protein; (2) unfolding individual domains followed cooperative dissociation into monomers; (3) two loosely structured forms monomer intermediates. It is assumed that one these monomeric (at 3.0) corresponds molten-globule state secondary structure, while other 2.0) represents partly denatured (misfolded) monomer, which retains no more than 50% regular structure. putative mechanism low β-barrel discussed theoretical model spatial