title: Identification of the internal axial ligand of HO2-cobalt(III)-bleomycin: 1H[15N] HSQC NMR investigation of bleomycin, deglycobleomycin, and their hydroperoxide-cobalt(III) complexes.
abstract: The identity of the axial ligand contributed by the drug in hydroperoxide-Co(III)-bleomycin and hydroperoxide-Co(III)-deglycobleomycin has been in doubt. With each structure, a combination of (1)H[(15)N] HSQC and HMBC and (1)H COSY and NOESY NMR spectroscopy was used to observe and completely assign the nonaromatic (15)N chemical shifts of natural abundance bleomycin in the two hydroperoxide-Co(III) structures. Together with the (15)N assignments from a published 1D (15)N spectrum, the results permitted the assignment of the primary amine nitrogen to an axial ligand position in both structures.
authors.affiliation: Department of Chemistry, University of Wisconsin-Milwaukee, P.O. Box 413, Milwaukee, Wisconsin 53201, USA.
authors.forename: Chaunwu
authors.initials: C
authors.lastname: Xia
authors.forename: F Holger
authors.initials: FH
authors.lastname: Försterling
authors.forename: David H
authors.initials: DH
authors.lastname: Petering
mesh_terms: D001761:Bleomycin / Q000031:analogs & derivatives* / Q000737:chemistry*; D003035:Cobalt / Q000737:chemistry*; D008024:Ligands; D009682:Magnetic Resonance Spectroscopy; D008956:Models, Chemical; D009584:Nitrogen / Q000737:chemistry; D017663:Peplomycin / Q000737:chemistry; D011485:Protein Binding; D011522:Protons; D013696:Temperature
chemical_list: D008024:Ligands; D011522:Protons; C030187:cobalt bleomycin; D001761:Bleomycin; D003035:Cobalt; D017663:Peplomycin; C033284:deglycobleomycin; D009584:Nitrogen