title: Development of a new approach for screening combinatorial libraries using MALDI-TOF-MS and HPLC-ESI-MS/MS.
abstract: Mass spectrometric techniques play a prominent role in the rapidly expanding field of high-throughput screening (HTS). In this paper, the authors present a novel qualitative approach for the screening of a small library of compounds using MALDI-TOF-MS and HPLC-ESI-MS/MS. Chymotrypsin (CT), a serine protease, was selected as the target protein. A well-known inhibitor of CT is chymostatin (CS), a naturally occurring peptide aldehyde, which is reported to be a mixture of 3 components-A, B, and C-differing only in one of the amino acids. The authors report that native CS mixture consists of 3 additional ring hydroxylated components and that each compound exists in 2 epimeric forms. In case of protein-binding compounds, only 1 of the epimers was found to be active. A unique feature of this study is the generation of a combinatorial library of CS derivatives applying a one-pot strategy followed by identification and structural elucidation of the library components. Analytical investigation of the library resulted in the identification of 22 compounds. After incubation with CT and centrifugal ultrafiltration, 10 compounds were detected as protein-binding ligands. Finally, the complementary potentials of MALDI-TOF-MS and HPLC-MS/MS in the screening of complex ligand mixtures have been discussed.
authors.affiliation: F.R. 8.5, Pharmaceutical and Medicinal Chemistry, Saarland Univeristy, P.O. Box 151150, D-66041 Saarbrücken, Germany.
authors.forename: Sonal
authors.initials: S
authors.lastname: Mathur
authors.forename: Marc
authors.initials: M
authors.lastname: Hassel
authors.forename: Frank
authors.initials: F
authors.lastname: Steiner
authors.forename: Klaus
authors.initials: K
authors.lastname: Hollemeyer
authors.forename: Rolf W
authors.initials: RW
authors.lastname: Hartmann
mesh_terms: D000818:Animals; D002417:Cattle; D002851:Chromatography, High Pressure Liquid; D002918:Chymotrypsin / Q000037:antagonists & inhibitors / Q000378:metabolism; D020650:Combinatorial Chemistry Techniques; D015195:Drug Design; D015394:Molecular Structure; D009842:Oligopeptides / Q000737:chemistry* / Q000378:metabolism; D019151:Peptide Library; D011485:Protein Binding; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
chemical_list: D009842:Oligopeptides; D019151:Peptide Library; C002101:chymostatin; D002918:Chymotrypsin