title: Engineering a Constrained Peptidic Scaffold towards Potent and Selective Furin Inhibitors.
abstract: We report the engineering of the monocyclic sunflower trypsin inhibitor (SFTI-1[1,14]) into a potent furin inhibitor. In a rational approach, we converted the native scaffold of this trypsin-like serine protease inhibitor into a subtilisin-like one by substitutions in the canonical and, particularly, in the substrate-binding loop. Although the substrate sequence for furin is Arg-X-Arg/Lys-Arg↓, the most potent inhibitor had a lysine at position P1. C-terminally truncated versions demonstrated the strongest activity, thus suggesting a lack of interaction between this motif and the surface of furin. This observation was further supported by molecular modeling. With an inhibition constant of 0.49 nm, the engineered peptide H-KRCKKSIPPICF-NH2 is a promising compound for further development of furin inhibitors aimed at controlling the activity of this protease in vitro and in vivo.
authors.affiliation: Clemens-Schöpf-Institut für organische und Biochemie, Technische Universität Darmstadt, Alarich-Weiss Strasse 4, 64287, Darmstadt, Germany.
authors.forename: Heiko
authors.initials: H
authors.lastname: Fittler
authors.affiliation: Clemens-Schöpf-Institut für organische und Biochemie, Technische Universität Darmstadt, Alarich-Weiss Strasse 4, 64287, Darmstadt, Germany.
authors.forename: Alexander
authors.initials: A
authors.lastname: Depp
authors.affiliation: Clemens-Schöpf-Institut für organische und Biochemie, Technische Universität Darmstadt, Alarich-Weiss Strasse 4, 64287, Darmstadt, Germany.
authors.forename: Olga
authors.initials: O
authors.lastname: Avrutina
authors.affiliation: Leibniz Institute for Age Research-Fritz Lipmann Institute (FLI), Beutenbergstrasse 11, 07745, Jena, Germany.
authors.forename: Sven O
authors.initials: SO
authors.lastname: Dahms
authors.affiliation: Leibniz Institute for Age Research-Fritz Lipmann Institute (FLI), Beutenbergstrasse 11, 07745, Jena, Germany.
authors.forename: Manuel E
authors.initials: ME
authors.lastname: Than
authors.affiliation: Helmholtz-Institute for Pharmaceutical Research Saarland (HIPS), Campus C2.3, 66123, Saarbrücken, Germany.
authors.forename: Martin
authors.initials: M
authors.lastname: Empting
authors.affiliation: Clemens-Schöpf-Institut für organische und Biochemie, Technische Universität Darmstadt, Alarich-Weiss Strasse 4, 64287, Darmstadt, Germany. kolmar@biochemie-tud.de.
authors.forename: Harald
authors.initials: H
authors.lastname: Kolmar
mesh_terms: D000595:Amino Acid Sequence; D001665:Binding Sites; D015195:Drug Design; D045683:Furin / Q000037:antagonists & inhibitors* / Q000378:metabolism; D006368:Helianthus / Q000378:metabolism; D007700:Kinetics; D056004:Molecular Dynamics Simulation; D010455:Peptides / Q000138:chemical synthesis / Q000737:chemistry* / Q000378:metabolism; D011480:Protease Inhibitors / Q000737:chemistry / Q000378:metabolism; D017434:Protein Structure, Tertiary
chemical_list: D010455:Peptides; D011480:Protease Inhibitors; D045683:Furin
keywords: Bowman-Birk inhibitor; SFTI-1; furin; protein engineering; rational design; structure-activity relationships