title: [Structure-functional studies of polymyxins. (1)-NMR analysis of polymyxin B and M conformation].
abstract: Spatial structures of two polymyxin antibiotics are compared by means of one- and two-dimensional 1H NMR spectroscopy. Cyclic parts of polymyxins B and M contain a system of hydrogen bonds including two beta-turns, however, the analysis of coupling constants 3JHN-C alpha H demonstrated that torsional angles phi of peptide bonds of the residues forming beta-turns in polymyxin M depend on the type of the anion. An increase in lability of the polymyxin M cyclic part in comparison with polymyxin B correlated with the selective cleavage of the peptide bond Dab8-Dab9 of this antibiotic with subtilisin. A similar correlation was found for a short analogue of polymyxin B, a cycloheptapeptide.
authors.forename: V V
authors.initials: VV
authors.lastname: Okhanov
authors.forename: P V
authors.initials: PV
authors.lastname: Dubovskiĭ
authors.forename: A I
authors.initials: AI
authors.lastname: Miroshnikov
mesh_terms: D009682:Magnetic Resonance Spectroscopy; D011112:Polymyxin B / Q000737:chemistry*; D011113:Polymyxins / Q000737:chemistry*; D013329:Structure-Activity Relationship
chemical_list: D011113:Polymyxins; D011112:Polymyxin B
vernacular_title: Strukturno-funktsional'nye issledovaniia polimiksinov. (1)IaMR-analiz konformatsii polimiksinov B i M.