title: Live cell labeling of native intracellular bacterial receptors using aniline-catalyzed oxime ligation.
abstract: Live cell fluorescent labeling of proteins has become a seminal tool in biology and has led to hallmark discoveries in diverse research areas such as protein trafficking, cell-to-cell interactions, and intracellular network dynamics. One of the main challenges, however, remains the ability to label intracellular proteins using fluorescent ligands with high specificity, all the while retaining viability of the targeted cells. Here, we present the first example of live cell labeling and imaging of an intracellular bacterial receptor involved in cell-to-cell communication (i.e., quorum sensing), using a novel two-step approach involving covalent attachment of a reactive mimic of the primary endogenous Pseudomonas aeruginosa quorum-sensing signal to its receptor, LasR, followed by aniline-catalyzed oxime formation between the modified receptor and a fluorescent BODIPY derivative. Our results indicate that LasR is not distributed evenly throughout the cytoplasmic membrane but is instead concentrated at the poles of the P. aeruginosa cell.
authors.affiliation: Department of Chemistry and National Institute for Biotechnology in the Negev, Ben-Gurion University of the Negev, Be'er-Sheva 84105, Israel.
authors.forename: Josep
authors.initials: J
authors.lastname: Rayo
authors.forename: Neri
authors.initials: N
authors.lastname: Amara
authors.forename: Pnina
authors.initials: P
authors.lastname: Krief
authors.forename: Michael M
authors.initials: MM
authors.lastname: Meijler
mesh_terms: D000595:Amino Acid Sequence; D000814:Aniline Compounds / Q000737:chemistry*; D001426:Bacterial Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D002384:Catalysis; D005456:Fluorescent Dyes / Q000737:chemistry*; D008969:Molecular Sequence Data; D015394:Molecular Structure; D010091:Oximes / Q000737:chemistry*; D011550:Pseudomonas aeruginosa; D053038:Quorum Sensing / Q000502:physiology; D011956:Receptors, Cell Surface / Q000737:chemistry / Q000378:metabolism*; D015534:Trans-Activators / Q000737:chemistry / Q000235:genetics / Q000378:metabolism
chemical_list: D000814:Aniline Compounds; D001426:Bacterial Proteins; D005456:Fluorescent Dyes; C080365:LasR protein, Pseudomonas aeruginosa; D010091:Oximes; D011956:Receptors, Cell Surface; D015534:Trans-Activators; C023650:aniline