title: Study on effect of lomefloxacin on human holo-transferrin in the presence of essential and nonessential amino acids: Spectroscopic and molecular modeling approaches.
abstract: The purpose of this study was to determine how lomefloxacin (LMF) interacts with human holo-transferrin (HTF) in the presence of two kinds of essential and nonessential amino acids. The investigations were carried out by fluorescence spectroscopy, zeta potential and molecular modeling techniques under imitated physiological conditions. We were able to determine the number of binding sites, the drug binding affinity to HTF in the presence of essential and nonessential amino acids and the quenching source of HTF. The interaction between HTF with LMF suggested that the microenvironment of the Trp residues was altered causing a strong static fluorescence quenching in the binary and ternary systems. The results pointed at the formation of a complex in the binary and ternary systems which caused an enhancement of the RLS intensity that was analyzed using synchronous fluorescence spectroscopy. The density functional theory (DFT) was employed to determine the amino acid residues on HTF that interacted with LMF. Also, Steric and van der Waals forces as well as the contribution of small amounts of hydrogen bonds were stronger or Tyr 71 in chain (b) than for 128 Trp in chain (a) of HTF.
authors.affiliation: Department of Biochemistry and Biophysics, Faculty of Sciences, Mashhad Branch, Islamic Azad University, Mashhad, Iran.
authors.forename: Somaye
authors.initials: S
authors.lastname: Marouzi
authors.affiliation: Department of Biochemistry and Biophysics, Faculty of Sciences, Mashhad Branch, Islamic Azad University, Mashhad, Iran.
authors.forename: Atena
authors.initials: A
authors.lastname: Sharifi Rad
authors.affiliation: Endoscopic and Minimally Invasive Surgery Research Center, Mashhad University of Medical Sciences, Mashhad, Iran.
authors.forename: Sima
authors.initials: S
authors.lastname: Beigoli
authors.affiliation: Department of Biochemistry and Biophysics, Faculty of Sciences, Mashhad Branch, Islamic Azad University, Mashhad, Iran.
authors.forename: Parisa
authors.initials: P
authors.lastname: Teimoori Baghaee
authors.affiliation: Department of Biochemistry and Biophysics, Faculty of Sciences, Mashhad Branch, Islamic Azad University, Mashhad, Iran.
authors.forename: Reza
authors.initials: R
authors.lastname: Assaran Darban
authors.affiliation: Department of Biochemistry and Biophysics, Faculty of Sciences, Mashhad Branch, Islamic Azad University, Mashhad, Iran. Electronic address: Chamani.j@ut.ac.ir.
authors.forename: Jamshidkhan
authors.initials: J
authors.lastname: Chamani
mesh_terms: D000601:Amino Acids, Essential / Q000494:pharmacology*; D004735:Energy Transfer; D024841:Fluoroquinolones / Q000378:metabolism* / Q000494:pharmacology*; D006801:Humans; D008958:Models, Molecular; D011485:Protein Binding / Q000187:drug effects; D011487:Protein Conformation / Q000187:drug effects; D013057:Spectrum Analysis; D013816:Thermodynamics; D014168:Transferrin / Q000737:chemistry / Q000378:metabolism*
chemical_list: D000601:Amino Acids, Essential; D024841:Fluoroquinolones; D014168:Transferrin; C053091:lomefloxacin
keywords: Amino acids; DFT; Human holo transferrin; Lomefloxacin; Spectroscopy