title: The orientation of the transition dipole moments of a polyene antibiotic Amphotericin B under UV-VIS studies.
abstract: Amphotericin B (AmB) belongs to naturally occurring fluorescent antibiotics, commonly used in the treatment of life-threatening fungal infections. Open question regarding mechanism of action of this molecule calls for its orientation and organization studies in biomembranes. Here, we present studies on linear dichroism and fluorescence polarization of AmB embedded in isotropic and oriented poly(vinyl) alcohol films to characterize their transition dipole moments to low energy excited electronic transitions S1 (2 Ag(-)) and S2 (1 Bu(+)). The dichroic ratio and fluorescence anisotropy data were analyzed for stretched PVA films doped AmB. The results show that the transition moment for absorption makes an angle φ = 27° ± 2° with the molecular axis of AmB defined by the film stretching direction. The angles between the absorption and emission transition moments have been found for both the low excited electronic states, S2 (β = 4° ± 5°) and S1 (β = 6° ± 5°). The fluorescence anisotropy analysis from the S2 state reveals additional component assigned to antiparallel AmB dimeric structure.
authors.affiliation: Department of Biophysics, Institute of Physics, Maria Curie-Sklodowska University, pl. M. Curie-Sklodowskiej 1, 20-031 Lublin, Poland. Electronic address: ktutaj@gmail.com.
authors.forename: Krzysztof
authors.initials: K
authors.lastname: Tutaj
authors.affiliation: Department of Biophysics, Institute of Physics, Maria Curie-Sklodowska University, pl. M. Curie-Sklodowskiej 1, 20-031 Lublin, Poland. Electronic address: radoslaw.szlazak@gmail.com.
authors.forename: Radoslaw
authors.initials: R
authors.lastname: Szlazak
authors.affiliation: Department of Biophysics, Institute of Physics, Maria Curie-Sklodowska University, pl. M. Curie-Sklodowskiej 1, 20-031 Lublin, Poland. Electronic address: starzyk.asia@gmail.com.
authors.forename: Joanna
authors.initials: J
authors.lastname: Starzyk
authors.affiliation: Department of Biophysics, Institute of Physics, Maria Curie-Sklodowska University, pl. M. Curie-Sklodowskiej 1, 20-031 Lublin, Poland. Electronic address: piotr.wasko@gmail.com.
authors.forename: Piotr
authors.initials: P
authors.lastname: Wasko
authors.affiliation: Department of Biophysics, Institute of Physics, Maria Curie-Sklodowska University, pl. M. Curie-Sklodowskiej 1, 20-031 Lublin, Poland. Electronic address: wojciech.grudzinski@umcs.pl.
authors.forename: Wojciech
authors.initials: W
authors.lastname: Grudzinski
authors.affiliation: Department of Biophysics, Institute of Physics, Maria Curie-Sklodowska University, pl. M. Curie-Sklodowskiej 1, 20-031 Lublin, Poland. Electronic address: wieslaw.gruszecki@umcs.pl.
authors.forename: Wieslaw I
authors.initials: WI
authors.lastname: Gruszecki
authors.affiliation: Department of Biophysics, Institute of Physics, Maria Curie-Sklodowska University, pl. M. Curie-Sklodowskiej 1, 20-031 Lublin, Poland. Electronic address: rafal.luchowski@umcs.pl.
authors.forename: Rafal
authors.initials: R
authors.lastname: Luchowski
mesh_terms: D000666:Amphotericin B / Q000737:chemistry*; D005454:Fluorescence Polarization; D011142:Polyvinyl Alcohol / Q000737:chemistry; D013050:Spectrometry, Fluorescence; D013056:Spectrophotometry, Ultraviolet
chemical_list: D000666:Amphotericin B; D011142:Polyvinyl Alcohol
keywords: Amphotericin B; Antifungal drug; Transition dipole moment direction