title: Sequencing of bacitracin A and related minor components by liquid chromatography/electrospray ionization ion trap tandem mass spectrometry.
abstract: A selective reversed-phase liquid chromatography/mass spectrometry (LC/MS(n)) method is described for the characterization of related compounds in commercial bacitracin samples. Mass spectral data for these polypeptide antibiotics were acquired on a LCQ ion trap mass spectrometer equipped with an electrospray ionization probe operated in the positive and negative ion mode. The LCQ ion trap is ideally suited for the sequencing of those linear side-chain cyclized peptides because it provides on-line LC/MS(n) capability. Using this method bacitracin A, 1-epibacitracin A, bacitracins B(1), B(2), B(3) and bacitracin F were sequenced and previous sequencing was confirmed. Bacitracins C(1), C(2), C(3), D, H(2) and H(3) were resolved chromatographically and their ring portion was sequenced for the first time. Four components not described in the literature (1-epibacitracin B(1), 1-epibacitracin B(2), 1-epibacitracin C(1) and H(4)) were sequenced completely for the first time. The main advantage of this hyphenated LC/MS(n) technique is the characterization of the related substances without time-consuming isolation and purification procedures.
authors.affiliation: Katholieke Universiteit Leuven, Faculteit Farmaceutische Wetenschappen, Laboratorium voor Farmaceutische Chemie en Analyse van Geneesmiddelen, E. Van Evenstraat 4, B-3000 Leuven, Belgium.
authors.forename: Cindy
authors.initials: C
authors.lastname: Govaerts
authors.affiliation: Katholieke Universiteit Leuven, Faculteit Farmaceutische Wetenschappen, Laboratorium voor Farmaceutische Chemie en Analyse van Geneesmiddelen, E. Van Evenstraat 4, B-3000 Leuven, Belgium.
authors.forename: Chunlan
authors.initials: C
authors.lastname: Li
authors.affiliation: Katholieke Universiteit Leuven, Faculteit Farmaceutische Wetenschappen, Laboratorium voor Farmaceutische Chemie en Analyse van Geneesmiddelen, E. Van Evenstraat 4, B-3000 Leuven, Belgium.
authors.forename: Jennifer
authors.initials: J
authors.lastname: Orwa
authors.affiliation: Katholieke Universiteit Leuven, Faculteit Farmaceutische Wetenschappen, Laboratorium voor Farmaceutische Chemie en Analyse van Geneesmiddelen, E. Van Evenstraat 4, B-3000 Leuven, Belgium.
authors.forename: Ann
authors.initials: A
authors.lastname: Van Schepdael
authors.affiliation: Katholieke Universiteit Leuven, Faculteit Farmaceutische Wetenschappen, Laboratorium voor Farmaceutische Chemie en Analyse van Geneesmiddelen, E. Van Evenstraat 4, B-3000 Leuven, Belgium.
authors.forename: Erwin
authors.initials: E
authors.lastname: Adams
authors.affiliation: Katholieke Universiteit Leuven, Faculteit Farmaceutische Wetenschappen, Laboratorium voor Farmaceutische Chemie en Analyse van Geneesmiddelen, E. Van Evenstraat 4, B-3000 Leuven, Belgium.
authors.forename: Eugène
authors.initials: E
authors.lastname: Roets
authors.affiliation: Katholieke Universiteit Leuven, Faculteit Farmaceutische Wetenschappen, Laboratorium voor Farmaceutische Chemie en Analyse van Geneesmiddelen, E. Van Evenstraat 4, B-3000 Leuven, Belgium.
authors.forename: Jos
authors.initials: J
authors.lastname: Hoogmartens
mesh_terms: D000595:Amino Acid Sequence; D000900:Anti-Bacterial Agents / Q000032:analysis* / Q000737:chemistry*; D001414:Bacitracin / Q000032:analysis* / Q000737:chemistry*; D002853:Chromatography, Liquid; D007477:Ions; D008969:Molecular Sequence Data; D015394:Molecular Structure; D010446:Peptide Fragments / Q000032:analysis / Q000737:chemistry; D021241:Spectrometry, Mass, Electrospray Ionization
chemical_list: D000900:Anti-Bacterial Agents; D007477:Ions; D010446:Peptide Fragments; D001414:Bacitracin; C026461:bacitracin A