Isolation, Co-Crystallization and Structure-Based Characterization of Anabaenopeptins as Highly Potent Inhibitors of Activated Thrombin Activatable Fibrinolysis Inhibitor (TAFIa).
Mature thrombin activatable fibrinolysis inhibitor (TAFIa) is a carboxypeptidase that stabilizes fibrin clots by removing C-terminal arginines and lysines from partially degraded fibrin. Inhibition of TAFIa stimulates the degradation of fibrin clots and may help to prevent thrombosis. Applying a lead finding approach based on literature-mining, we discovered that anabaenopeptins, cyclic peptides produced by cyanobacteria, were potent inhibitors of TAFIa with IC50 values as low as 1.5 nM. We describe the isolation and structure elucidation of 20 anabaenopeptins, including 13 novel congeners, as well as their pronounced structure-activity relationships (SAR) with respect to inhibition of TAFIa. Crystal structures of the anabaenopeptins B, C and F bound to the surrogate protease carboxypeptidase B revealed the binding modes of these large (~850 Da) compounds in detail and explained the observed SAR, i.e. the strong dependence of the potency on a basic (Arg, Lys) exocyclic residue that addressed the S1' binding pocket, and a broad tolerance towards substitutions in the pentacyclic ring that acted as a plug of the active site.
Sanofi-Aventis Deutschland GmbH, Industriepark Höchst, 65926, Frankfurt am Main, Germany.
Herman
H
Schreuder
Sanofi-Aventis Deutschland GmbH, Industriepark Höchst, 65926, Frankfurt am Main, Germany.
Alexander
A
Liesum
Sanofi-Aventis Deutschland GmbH, Industriepark Höchst, 65926, Frankfurt am Main, Germany.
Petra
P
Lönze
Sanofi-Aventis Deutschland GmbH, Industriepark Höchst, 65926, Frankfurt am Main, Germany.
Heike
H
Stump
Sanofi-Aventis Deutschland GmbH, Industriepark Höchst, 65926, Frankfurt am Main, Germany.
Holger
H
Hoffmann
Sanofi-Aventis Deutschland GmbH, Industriepark Höchst, 65926, Frankfurt am Main, Germany.
Matthias
M
Schiell
Sanofi-Aventis Deutschland GmbH, Industriepark Höchst, 65926, Frankfurt am Main, Germany.
Michael
M
Kurz
Sanofi-Aventis Deutschland GmbH, Industriepark Höchst, 65926, Frankfurt am Main, Germany.
Luigi
L
Toti
Sanofi-Aventis Deutschland GmbH, Industriepark Höchst, 65926, Frankfurt am Main, Germany.
Armin
A
Bauer
Sanofi-Aventis Deutschland GmbH, Industriepark Höchst, 65926, Frankfurt am Main, Germany.
Christopher
C
Kallus
Sanofi-Aventis Deutschland GmbH, Industriepark Höchst, 65926, Frankfurt am Main, Germany.
Christine
C
Klemke-Jahn
Sanofi-Aventis Deutschland GmbH, Industriepark Höchst, 65926, Frankfurt am Main, Germany.
Jörg
J
Czech
Cyano Biotech GmbH, Magnusstraße 11, 12489, Berlin, Germany.
Dan
D
Kramer
Cyano Biotech GmbH, Magnusstraße 11, 12489, Berlin, Germany.
Heike
H
Enke
Cyano Biotech GmbH, Magnusstraße 11, 12489, Berlin, Germany.|Interfaculty Institute for Microbiology and Infection Research, Eberhard Karls University Tübingen, Auf der Morgenstelle 28, 72076, Tübingen, Germany.
Timo H J
THJ
Niedermeyer
Sanofi, 153 Second Avenue, MA-02451, Waltham, USA.
Vincent
V
Morrison
Sanofi, 153 Second Avenue, MA-02451, Waltham, USA.
Vasant
V
Kumar
Sanofi-Aventis Deutschland GmbH, Industriepark Höchst, 65926, Frankfurt am Main, Germany.|Department of Chemical Biology, Helmholtz Centre for Infection Research, Inhoffenstraße 7, 38124 Braunschweig, Germany.
Mark
M
Brönstrup
D001426:Bacterial Proteins / Q000737:chemistry / Q000494:pharmacology; D043424:Carboxypeptidase B / Q000037:antagonists & inhibitors / Q000737:chemistry; D025901:Carboxypeptidase B2 / Q000037:antagonists & inhibitors* / Q000737:chemistry; D020134:Catalytic Domain; D003460:Crystallization; D018360:Crystallography, X-Ray; D000458:Cyanobacteria / Q000737:chemistry; D005342:Fibrinolysis / Q000187:drug effects*; D006801:Humans; D008958:Models, Molecular; D010456:Peptides, Cyclic / Q000737:chemistry* / Q000302:isolation & purification / Q000494:pharmacology*; D013329:Structure-Activity Relationship
D001426:Bacterial Proteins; D010456:Peptides, Cyclic; C496665:anabaenopeptin B; C436355:anabaenopeptin F; D043424:Carboxypeptidase B; D025901:Carboxypeptidase B2