title: Phosphono Bisbenzguanidines as Irreversible Dipeptidomimetic Inhibitors and Activity-Based Probes of Matriptase-2.
abstract: Matriptase-2, a type II transmembrane serine protease, plays a key role in human iron homeostasis. Inhibition of matriptase-2 is considered as an attractive strategy for the treatment of iron-overload diseases, such as hemochromatosis and β-thalassemia. In the present study, synthetic routes to nine dipeptidomimetic inactivators were developed. Five active compounds (41-45) were identified and characterized kinetically as irreversible inhibitors of matriptase-2. In addition to a phosphonate warhead, these dipeptides possess two benzguanidine moieties as arginine mimetics to provide affinity for matriptase-2 by binding to the S1 and S3/S4 subpockets, respectively. This binding mode was strongly supported by covalent docking analysis. Compounds 41-45 were obtained as mixtures of two diastereomers and were therefore separated into the single epimers. Compound 45 A, with S configuration at the N-terminal amino acid and R configuration at the phosphonate carbon atom, was the most potent matriptase-2 inactivator with a rate constant of inactivation of 2790 m(-1)  s(-1) and abolished the activity of membrane-bound matriptase-2 on the surface of intact cells. Based on the chemotyp of phosphono bisbenzguanidines, the design and synthesis of a fluorescent probe (51 A) by insertion of a coumarin label is described. The in-gel fluorescence detection of matriptase-2 was demonstrated by applying 51 A as the first activity-based probe for this enzyme.
authors.affiliation: Pharmaceutical Institute, Pharmaceutical Chemistry I, University of Bonn, An der Immenburg 4, 53121, Bonn, Germany.
authors.forename: Daniela
authors.initials: D
authors.lastname: Häußler
authors.affiliation: Pharmaceutical Institute, Pharmaceutical Chemistry I, University of Bonn, An der Immenburg 4, 53121, Bonn, Germany.
authors.forename: Martin
authors.initials: M
authors.lastname: Mangold
authors.affiliation: Pharmaceutical Institute, Pharmaceutical Chemistry I, University of Bonn, An der Immenburg 4, 53121, Bonn, Germany.|Department of Life Science Informatics, B-IT, LIMES Program Unit Chemical Biology and Medicinal Chemistry, University of Bonn, Dahlmannstrasse 2, 53113, Bonn, Germany.
authors.forename: Norbert
authors.initials: N
authors.lastname: Furtmann
authors.affiliation: Department of Gastrointestinal Microbiology, German Institute of Human Nutrition Potsdam-Rehbruecke, Arthur-Scheunert-Allee 114-116, 14558, Nuthetal, Germany.
authors.forename: Annett
authors.initials: A
authors.lastname: Braune
authors.affiliation: Department of Gastrointestinal Microbiology, German Institute of Human Nutrition Potsdam-Rehbruecke, Arthur-Scheunert-Allee 114-116, 14558, Nuthetal, Germany.
authors.forename: Michael
authors.initials: M
authors.lastname: Blaut
authors.affiliation: Department of Life Science Informatics, B-IT, LIMES Program Unit Chemical Biology and Medicinal Chemistry, University of Bonn, Dahlmannstrasse 2, 53113, Bonn, Germany.
authors.forename: Jürgen
authors.initials: J
authors.lastname: Bajorath
authors.affiliation: Pharmaceutical Institute, Pharmaceutical Chemistry I, University of Bonn, An der Immenburg 4, 53121, Bonn, Germany.
authors.forename: Marit
authors.initials: M
authors.lastname: Stirnberg
authors.affiliation: Pharmaceutical Institute, Pharmaceutical Chemistry I, University of Bonn, An der Immenburg 4, 53121, Bonn, Germany. guetschow@uni-bonn.de.
authors.forename: Michael
authors.initials: M
authors.lastname: Gütschow
mesh_terms: D000818:Animals; D001665:Binding Sites; D020134:Catalytic Domain; D002417:Cattle; D003374:Coumarins / Q000737:chemistry; D015951:Factor Xa / Q000737:chemistry / Q000378:metabolism; D005456:Fluorescent Dyes / Q000737:chemistry; D006146:Guanidines / Q000138:chemical synthesis / Q000737:chemistry* / Q000378:metabolism; D006801:Humans; D007700:Kinetics; D008565:Membrane Proteins / Q000037:antagonists & inhibitors* / Q000378:metabolism; D062105:Molecular Docking Simulation; D057786:Peptidomimetics; D010758:Phosphorus / Q000737:chemistry; D012697:Serine Endopeptidases / Q000378:metabolism; D015842:Serine Proteinase Inhibitors / Q000138:chemical synthesis / Q000737:chemistry* / Q000378:metabolism; D013237:Stereoisomerism; D014357:Trypsin / Q000737:chemistry / Q000378:metabolism
chemical_list: D003374:Coumarins; D005456:Fluorescent Dyes; D006146:Guanidines; D008565:Membrane Proteins; D057786:Peptidomimetics; D015842:Serine Proteinase Inhibitors; D010758:Phosphorus; C030123:coumarin; D012697:Serine Endopeptidases; C467801:matriptase 2; D014357:Trypsin; D015951:Factor Xa
keywords: enzymes; fluorescent probes; inhibitors; peptidomimetics; serine proteases