title: A Fluorescent Probe Distinguishes between Inhibition of Early and Late Steps of Lipopolysaccharide Biogenesis in Whole Cells.
abstract: Lipopolysaccharide (LPS) biogenesis in Gram-negative organisms involves its biosynthesis in the cytoplasm and subsequent transport across three cellular compartments to the cell surface. We developed a fluorescent probe that allows us to determine the spatial distribution of LPS in whole cells. We show that polymyxin B nonapeptide (PMBN) containing a dansyl fluorophore specifically binds to LPS in membranes. We show that this probe detects decreases in LPS levels on the cell surface when LPS biosynthesis is inhibited at an early step. We also can detect accumulation of LPS in particular subcellular locations when LPS assembly is blocked during transport, allowing us to differentiate inhibitors targeting early and late stages of LPS biogenesis.
authors.affiliation: Department of Chemistry and Chemical Biology, Harvard University , Cambridge, Massachusetts 02138, United States.
authors.forename: Eileen
authors.initials: E
authors.lastname: Moison
authors.affiliation: Department of Chemistry and Chemical Biology, Harvard University , Cambridge, Massachusetts 02138, United States.
authors.forename: Ran
authors.initials: R
authors.lastname: Xie
authors.affiliation: Department of Chemistry and Chemical Biology, Harvard University , Cambridge, Massachusetts 02138, United States.
authors.forename: Ge
authors.initials: G
authors.lastname: Zhang
authors.affiliation: Department of Chemistry and Chemical Biology, Harvard University , Cambridge, Massachusetts 02138, United States.
authors.forename: Matthew D
authors.initials: MD
authors.lastname: Lebar
authors.affiliation: Department of Chemistry and Chemical Biology, Harvard University , Cambridge, Massachusetts 02138, United States.
authors.forename: Timothy C
authors.initials: TC
authors.lastname: Meredith
authors.affiliation: Department of Chemistry and Chemical Biology, Harvard University , Cambridge, Massachusetts 02138, United States.
authors.forename: Daniel
authors.identifier: 0000-0002-8296-1424
authors.initials: D
authors.lastname: Kahne
mesh_terms: D005456:Fluorescent Dyes / Q000378:metabolism*; D006090:Gram-Negative Bacteria / Q000378:metabolism; D008070:Lipopolysaccharides / Q000096:biosynthesis*; D011112:Polymyxin B / Q000031:analogs & derivatives / Q000737:chemistry / Q000378:metabolism
chemical_list: D005456:Fluorescent Dyes; D008070:Lipopolysaccharides; C038934:polymyxin B nonapeptide; D011112:Polymyxin B