Using liposome model, a direct relationship between changes in the molecular structure of the nonspecific porins of the outer membrane of Gram-negative bacteria that occur under the influence of temperature and the functional activity of these proteins has been established. OmpF porin from Y. ruckeri , bacteria pathogenic for fish and classical OmpF porin from E. coli as a comparison protein were used in the study. It was found that unlike porin from E. coli , OmpF porin from Y. ruckeri is more resistant to temperature. For both proteins, stable release of the fluorophore was observed up to a temperature not exceeding the critical temperature of the dissociation of trimers of the proteins into monomers, at a higher temperature a sharp decrease in the channel- forming activity of the porins was found. It is suggested that irreversible conformational changes in the porin monomers that occur as a result of thermal denaturation "do not allow" them to form a conducting trimeric channel even in a lipid environment.
porin, nanopores, liposomal model, functional activity
1. Majd S., Yusko E.C., Billeh Y.N., Macrae M.X., Yang J., Mayer M. Applications of biological pores in nanomedicine, sensing, and nanoelectronics. Curr Opin Biotechnol., 2010, vol. 21, pp. 439-476.
2. Pradeep H., Rajanikant G.K. Nanochannels: biological channel analogues. IET Nanobiotechnol., 2012, vol. 6, no. 2, pp. 63-70.
3. Schulz G.E. The structure of bacterial outer membrane proteins. Biochim. Biophys. Acta, 2002, vol. 1565, pp. 308-317.
4. Koebnick R., Locher K.P., Van Gelder P. Structure and function of bacterial outer membrane proteins: barrels in a nutshell. Mol. Microbiol., 2000, vol. 37, pp. 239-253.
5. Naberezhnyh G.A., Karpenko A.A, Gorbach V. I., Homenko. V.A., Novikova O.D., Kul'chin Yu.N. Issledovanie morfologii nadmolekulyarnyh struktur belka-porina iz Yersinia pseudotuberculosis v lipidnom bisloe metodom atomno-silovoy mikroskopii. Aktual'nye voprosy biologicheskoy fiziki i himii. BFFH - 2016, 2016, t. 2, c. 32-36. [Naberezhnykh G. A, Karpenko A.A., Gorbach V. I., Khomenko V.A., Novikova O.D., Kulchin Yu.N. Morphology of supramolecular structures of pore-forming protein from Yersinia pseudotuberculosis in lipid bilayer by atomic force microscopy. Russian Journal of Biological Physics and Chemistry, 2016, vol. 2, pp. 32-36. (In Russ.)]
6. Novikova O.D., Kim N.Yu., Luk'yanov P.A., Emel'yanenko V.I., Kuznecova S.M., Lihackaya G.N., Solov'eva T.F. Vliyanie rN na strukturu i funkcional'nuyu aktivnost' porina iz naruzhnoy membrany Yersinia pseudotuberculosis (iersinina) Soobschenie 2. rN-Inducirovannye konformacionnye intermediaty porina iz naruzhnoy membrany Y. pseudotuberculosis. Biol. membrany, 2007, t. 24, № 2, s. 159-168. [Novikova O. D., Kim N. Yu., Luk’yanov P. A., Likhatskaya G. N., Emel’yanenko V. I., Solov’eva T. F. 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. Membrane and Cell Biology, 2007, vol. 1, no. 2, pp. 154-162. (In Russ.)]
7. Novikova O.D., Chistyulin D.K., Khomenko V.A., Sidorin E.V., Kim N.Yu., Sanina N.M., Portnyagina O.Yu., Solov'eva T.F., Uversky V.N., Shnyrov V.L. Peculiarities of thermal denaturation of OmpF porin from Yersinia ruckeri. Molecular BioSystems, 2017, vol. 13, pp. 1854-1862.
8. Rosenbusch J.P. Characterization of the major envelope protein from Escherichia coli. Regular arrangement on the peptidoglycan and unusual dodecyl sulfate binding. J. Biol. Chem., 1974, vol. 249, no. 24, pp. 8019-8029.
