title: Peptide exosite inhibitors of factor VIIa as anticoagulants.
abstract: Potent anticoagulants have been derived by targeting the tissue factor-factor VIIa complex with naive peptide libraries displayed on M13 phage. The peptides specifically block the activation of factor X with a median inhibitory concentration of 1 nM and selectively inhibit tissue-factor-dependent clotting. The peptides do not bind to the active site of factor VIIa; rather, they work by binding to an exosite on the factor VIIa protease domain, and non-competitively inhibit activation of factor X and amidolytic activity. One such peptide (E-76) has a well defined structure in solution determined by NMR spectroscopy that is similar to the X-ray crystal structure when complexed with factor VIIa. These structural and functional studies indicate an allosteric 'switch' mechanism of inhibition involving an activation loop of factor VIIa and represent a new framework for developing inhibitors of serine proteases.
authors.affiliation: Department of Protein Engineering, Genentech, Inc., South San Francisco, California 94080, USA.
authors.forename: M S
authors.initials: MS
authors.lastname: Dennis
authors.forename: C
authors.initials: C
authors.lastname: Eigenbrot
authors.forename: N J
authors.initials: NJ
authors.lastname: Skelton
authors.forename: M H
authors.initials: MH
authors.lastname: Ultsch
authors.forename: L
authors.initials: L
authors.lastname: Santell
authors.forename: M A
authors.initials: MA
authors.lastname: Dwyer
authors.forename: M P
authors.initials: MP
authors.lastname: O'Connell
authors.forename: R A
authors.initials: RA
authors.lastname: Lazarus
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D000925:Anticoagulants / Q000494:pharmacology*; D001665:Binding Sites; D016384:Consensus Sequence; D018360:Crystallography, X-Ray; D004792:Enzyme Precursors / Q000378:metabolism; D015942:Factor VIIa / Q000037:antagonists & inhibitors* / Q000737:chemistry; D005170:Factor X / Q000037:antagonists & inhibitors / Q000378:metabolism; D006801:Humans; D008958:Models, Molecular; D008969:Molecular Sequence Data; D009842:Oligopeptides / Q000302:isolation & purification / Q000494:pharmacology*; D019151:Peptide Library; D010455:Peptides / Q000302:isolation & purification / Q000494:pharmacology*; D011487:Protein Conformation; D011817:Rabbits; D015842:Serine Proteinase Inhibitors / Q000032:analysis / Q000494:pharmacology*; D013925:Thromboplastin / Q000378:metabolism
chemical_list: D000925:Anticoagulants; D004792:Enzyme Precursors; D009842:Oligopeptides; D019151:Peptide Library; D010455:Peptides; D015842:Serine Proteinase Inhibitors; C406584:peptide E-76; D005170:Factor X; D013925:Thromboplastin; D015942:Factor VIIa