Determining the Orientation of Porins in Planar Lipid Bilayers.

Single-channel planar lipid bilayer (PLB) recording of bacterial porins has revealed molecular details of transport across the outer membrane of Gram-negative bacteria, including antibiotic permeation and protein translocation. To explore directional transport processes across cellular membranes, the orientation of porins or other pore-forming proteins must be established in a lipid bilayer prior to experimentation. Here, we describe a direct method for determining the orientation of porins in a PLB-with a focus on E. coli OmpF-by using targeted covalent modification of cysteine mutants. Each of the two possible orientations can be correlated with the porin conductance asymmetry, such that thereafter an I-V curve taken at the start of an experiment will suffice to establish orientation.

Citation

Sandra A Ionescu, Sejeong Lee, Hagan Bayley. Determining the Orientation of Porins in Planar Lipid Bilayers. Methods in molecular biology (Clifton, N.J.). 2021;2186:51-62

Mesh Tags

Substances

PMID: 32918729

search → result