Native and chemically modified porin channels from Salmonella typhi Ty2 in planar lipid bilayers

FEBS Letters

Lobos, Sergio¹  Mora, Guido¹  Calderón, Inés¹  Labarca, Pedro² 

[1] Group of Molecular Neurobiology, Laboratory of Microbiology, Department of Cell Biology, Catholic University of Chile, PO Box 114-D, Santiago, Chile;Group of Molecular Neurobiology, Department of Cell Biology, Laboratory of Neurophysiology, Catholic University of Chile, PO Box 114-D, Santiago, Chile

关键词: (Salmonella typhi Ty2) Porin Pyridoxal phosphate Planar bilayer;   

DOI  :  10.1016/0014-5793(86)80328-3

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

Native porins, from Salmonella typhi Ty2 outer membrane, and porins alkylated with pyridoxal phosphate (Plp) were studied in planar lipid bilayers. The conductance of bilayers exposed to native or chemically modified porins increases in discrete jumps. Conductance histograms for native porins displayed two major peaks at 1.7 and 6.7 nS (in 0.5 M KCl). On the other hand, Plp-treated porins exhibited a single major peak at 1 nS. The relation between bilayer conductance and native porin concentration was linear. However, this relation became logarithmic in the presence of modified porins. The results support the notion that alkaline reduction of S. typhi Ty2 porins with Plp dissociates porin channel trimers in a reversible fashion.

【 授权许可】

Unknown