title: Labeling and Selective Inactivation of Gram-Positive Bacteria Employing Bimodal Photoprobes with Dual Readouts.
abstract: Carbohydrate-conjugated silicon(IV) phthalocyanines with bimodal photoactivity were developed as probes with both fluorescent labeling and photosensitizing capabilities, and the concomitant fluorescent labeling and photoinduced inactivation of Gram-positive and Gram-negative models was explored. The maltohexaose-conjugated photoprobe provides a dual readout to distinguish between both groups of pathogens, as only the Gram-positive species was inactivated, even though both appeared labeled with near-infrared luminescence. Antibiotic resistance did not hinder the phototoxic effect, as even the methicillin-resistant pathogen Staphylococcus aureus (MRSA) was completely photoinactivated. Time-resolved confocal fluorescence microscopy analysis suggests that the photoprobe sticks onto the outer rim of the microorganisms, explaining the resistance of Gram-negative species on the basis of their membrane constitution. The mannose-conjugated photoprobe yields a different readout because it is able to label and to inactivate only the Gram-positive strain.
authors.affiliation: European Institute for Molecular Imaging, Waldeyerstr. 15, 48149, Münster, Germany. anzhela.galstyan@wwu.de.|Physikalisches Institut and Center for Nanotechnology (CeNTech), Westfälische Wilhelms-Universität Münster, Heisenbergstr. 11, 48149, Münster, Germany. anzhela.galstyan@wwu.de.
authors.forename: Anzhela
authors.initials: A
authors.lastname: Galstyan
authors.affiliation: Institut für Medizinische Mikrobiologie, Universitätsklinikum Münster, Domagkstr. 10, 48149, Münster, Germany.
authors.forename: Desiree
authors.initials: D
authors.lastname: Block
authors.affiliation: Institut für Medizinische Mikrobiologie, Universitätsklinikum Münster, Domagkstr. 10, 48149, Münster, Germany.
authors.forename: Silke
authors.initials: S
authors.lastname: Niemann
authors.affiliation: Physikalisches Institut and Center for Nanotechnology (CeNTech), Westfälische Wilhelms-Universität Münster, Heisenbergstr. 11, 48149, Münster, Germany.
authors.forename: Malte C
authors.initials: MC
authors.lastname: Grüner
authors.affiliation: Dip. di Bioscienze Università degli Studi di Parma, NEST, Istituto Nanoscienze CNR, viale delle Scienze 11A, 43124, Parma, Italia.
authors.forename: Stefania
authors.initials: S
authors.lastname: Abbruzzetti
authors.affiliation: Fondazione Istituto Italiano di Tecnologia, Via Morego, 30, 16163, Genova, Italy.
authors.forename: Michele
authors.initials: M
authors.lastname: Oneto
authors.affiliation: Organisch-Chemisches Institut, Westfälische Wilhelms-Universität Münster, Corrensstr. 40, 48149, Münster, Germany.
authors.forename: Constantin G
authors.initials: CG
authors.lastname: Daniliuc
authors.affiliation: European Institute for Molecular Imaging, Waldeyerstr. 15, 48149, Münster, Germany.
authors.forename: Sven
authors.initials: S
authors.lastname: Hermann
authors.affiliation: Dip. di Fisica e Scienze della Terra, Università degli Studi di Parma, NEST, Istituto Nanoscienze CNR, viale delle Scienze 7A, 43124, Parma, Italia.
authors.forename: Cristiano
authors.initials: C
authors.lastname: Viappiani
authors.affiliation: European Institute for Molecular Imaging, Waldeyerstr. 15, 48149, Münster, Germany.|Klinik für Nuklearmedizin, Universitätsklinikum Münster, Albert Schweitzer-Campus 1, 48149, Münster, Germany.
authors.forename: Michael
authors.initials: M
authors.lastname: Schäfers
authors.affiliation: Institut für Medizinische Mikrobiologie, Universitätsklinikum Jena, Erlanger Allee 101, 07747, Jena, Germany.
authors.forename: Bettina
authors.initials: B
authors.lastname: Löffler
authors.affiliation: Physikalisches Institut and Center for Nanotechnology (CeNTech), Westfälische Wilhelms-Universität Münster, Heisenbergstr. 11, 48149, Münster, Germany. ca.s@wwu.de.
authors.forename: Cristian A
authors.initials: CA
authors.lastname: Strassert
authors.affiliation: European Institute for Molecular Imaging, Waldeyerstr. 15, 48149, Münster, Germany. faustan@wwu.de.
authors.forename: Andreas
authors.initials: A
authors.lastname: Faust
mesh_terms: D002241:Carbohydrates / Q000737:chemistry*; D006094:Gram-Positive Bacteria / Q000737:chemistry / Q000187:drug effects*; D007211:Indoles / Q000737:chemistry*; D049449:Luminescence; D055624:Methicillin-Resistant Staphylococcus aureus / Q000737:chemistry / Q000187:drug effects*; D017319:Photosensitizing Agents / Q000737:chemistry* / Q000494:pharmacology; D012821:Silanes / Q000737:chemistry*; D013211:Staphylococcus aureus / Q000737:chemistry / Q000187:drug effects*
chemical_list: D002241:Carbohydrates; D007211:Indoles; D017319:Photosensitizing Agents; D012821:Silanes
keywords: fluorescence spectroscopy; fluorescent probes; photophysics; silicon; singlet oxygen