Ionic liquids effects on the permeability of photosynthetic membranes probed by the electrochromic shift of endogenous carotenoids.
Ionic liquids (ILs) are promising materials exploited as solvents and media in many innovative applications, some already used at the industrial scale. The chemical structure and physicochemical properties of ILs can differ significantly according to the specific applications for which they have been synthesized. As a consequence, their interaction with biological entities and toxicity can vary substantially. To select highly effective and minimally harmful ILs, these properties need to be investigated. Here we use the so called chromatophores--protein-phospholipid membrane vesicles obtained from the photosynthetic bacterium Rhodobacter sphaeroides--to assess the effects of imidazolinium and pyrrolidinium ILs, with chloride or dicyanamide as counter anions, on the ionic permeability of a native biological membrane. The extent and modalities by which these ILs affect the ionic conductivity can be studied in chromatophores by analyzing the electrochromic response of endogenous carotenoids, acting as an intramembrane voltmeter at the molecular level. We show that chromatophores represent an in vitro experimental model suitable to probe permeability changes induced in cell membranes by ILs differing in chemical nature, degree of oxygenation of the cationic moiety and counter anion.
Dipartimento di Farmacia e Biotecnologie, FaBiT, Università di Bologna, Via Irnerio 42, 40126 Bologna, Italy.
Marco
M
Malferrari
Centro Interdipartimentale di Ricerca Industriale Energia e Ambiente (CIRI EA), Università di Bologna, Via Sant'Alberto 163, 48123 Ravenna, Italy.
Danilo
D
Malferrari
Dipartimento di Farmacia e Biotecnologie, FaBiT, Università di Bologna, Via Irnerio 42, 40126 Bologna, Italy. Electronic address: francesco.francia@unibo.it.
Francesco
F
Francia
Centro Interdipartimentale di Ricerca Industriale Energia e Ambiente (CIRI EA), Università di Bologna, Via Sant'Alberto 163, 48123 Ravenna, Italy; Dipartimento di Chimica "G. Ciamician", Università di Bologna, Via Selmi 2, 40126 Bologna, Italy.
Paola
P
Galletti
Centro Interdipartimentale di Ricerca Industriale Energia e Ambiente (CIRI EA), Università di Bologna, Via Sant'Alberto 163, 48123 Ravenna, Italy; Dipartimento di Chimica "G. Ciamician", Università di Bologna, Via Selmi 2, 40126 Bologna, Italy.
Emilio
E
Tagliavini
Dipartimento di Farmacia e Biotecnologie, FaBiT, Università di Bologna, Via Irnerio 42, 40126 Bologna, Italy; Consorzio Nazionale Interuniversitario per le Scienze Fisiche della Materia (CNISM), c/o Dipartimento di Fisica e Astronomia (DIFA), Università di Bologna, Via Irnerio 46, 40126 Bologna, Italy.
Giovanni
G
Venturoli
D000465:Algorithms; D020130:Bacterial Chromatophores / Q000187:drug effects / Q000378:metabolism*; D002338:Carotenoids / Q000378:metabolism*; D002712:Chlorides / Q000737:chemistry; D048288:Imidazolines / Q000737:chemistry; D052578:Ionic Liquids / Q000737:chemistry* / Q000494:pharmacology; D007700:Kinetics; D009682:Magnetic Resonance Spectroscopy; D015394:Molecular Structure; D010084:Oxidation-Reduction; D010539:Permeability / Q000187:drug effects; D011759:Pyrrolidines / Q000737:chemistry; D012242:Rhodobacter sphaeroides / Q000187:drug effects / Q000378:metabolism*; D013053:Spectrophotometry; D017550:Spectroscopy, Fourier Transform Infrared
D002712:Chlorides; D048288:Imidazolines; D052578:Ionic Liquids; D011759:Pyrrolidines; D002338:Carotenoids
Carotenoid shift; Chromatophores; Ionic liquids; Phospholipidic membranes; Photosynthesis