title: Chemically Induced Changes to Membrane Permeability in Living Cells Probed with Nonlinear Light Scattering.
abstract: Second-harmonic light scattering (SHS) permits characterization of membrane-specific molecular transport in living cells. Herein, we demonstrate the use of time-resolved SHS for quantifying chemically induced enhancements in membrane permeability. As proof of concept, we examine the enhanced permeability of the cytoplasmic membrane in living Escherichia coli following addition of extracellular adenosine triphosphate (ATPe). The transport rate of the hydrophobic cation, malachite green, increases nearly an order of magnitude following addition of 0.1 mM ATPe. The absence of an ATPe-enhanced permeability in liposomes strongly suggests the induced effect is protein-mediated. The utility of SHS for elucidating the mechanism of action of antimicrobials is discussed.
authors.affiliation: Department of Chemistry, Temple University, 1901 North 13th Street, Philadelphia, Pennsylvania 19122, United States.
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Wilhelm
authors.affiliation: Department of Chemistry, Temple University, 1901 North 13th Street, Philadelphia, Pennsylvania 19122, United States.
authors.forename: Mohammad
authors.initials: M
authors.lastname: Sharifian Gh
authors.affiliation: Department of Chemistry, Temple University, 1901 North 13th Street, Philadelphia, Pennsylvania 19122, United States.
authors.forename: Hai-Lung
authors.initials: HL
authors.lastname: Dai
mesh_terms: D000255:Adenosine Triphosphate / Q000737:chemistry / Q000502:physiology*; D001692:Biological Transport; D002462:Cell Membrane / Q000378:metabolism*; D002463:Cell Membrane Permeability; D004396:Coloring Agents / Q000737:chemistry / Q000378:metabolism; D004926:Escherichia coli / Q000378:metabolism; D007700:Kinetics; D008027:Light; D012394:Rosaniline Dyes / Q000737:chemistry / Q000378:metabolism; D012542:Scattering, Radiation; D053835:Unilamellar Liposomes / Q000737:chemistry
chemical_list: D004396:Coloring Agents; D012394:Rosaniline Dyes; D053835:Unilamellar Liposomes; C005095:malachite green; D000255:Adenosine Triphosphate