TY - JOUR

T1 - Bicyclic peptide inhibitor of urokinase-type plasminogen activator

T2 - mode of action

AU - Roodbeen, Renée

AU - Jensen, Berit Paaske

AU - Jiang, Longguang

AU - Jensen, Jan Kristian

AU - Christensen, Anni

AU - Nielsen, Jakob T.

AU - Huang, Mingdong

AU - Mulder, Frans

AU - Nielsen, Niels Chr.

AU - Andreasen, Peter

AU - Jensen, Knud Jørgen

N1 - Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

PY - 2013

Y1 - 2013

N2 - The development of protease inhibitors for pharmacological intervention has taken a new turn with the use of peptide-based inhibitors. Here, we report the rational design of bicyclic peptide inhibitors of the serine protease urokinase-type plasminogen activator (uPA), based on the established monocyclic peptide, upain-2. It was successfully converted to a bicyclic peptide, without loss of inhibitory properties. The aim was to produce a peptide cyclised by an amide bond with an additional stabilising across-the-ring covalent bond. We expected this bicyclic peptide to exhibit a lower entropic burden upon binding. Two bicyclic peptides were synthesised with affinities similar to that of upain-2, and their binding energetics were evaluated by isothermal titration calorimetry. Indeed, compared to upain-2, the bicyclic peptides showed reduced loss of entropy upon binding to uPA. We also investigated the solution structures of the bicyclic peptide by NMR spectroscopy to map possible conformations. An X-ray structure of the bicyclic-peptide-uPA complex confirmed an interaction similar to that for the previous upain-1/upain-2-uPA complexes. These physical studies of the peptide-protease interactions will aid future designs of bicyclic peptide protease inhibitors.

AB - The development of protease inhibitors for pharmacological intervention has taken a new turn with the use of peptide-based inhibitors. Here, we report the rational design of bicyclic peptide inhibitors of the serine protease urokinase-type plasminogen activator (uPA), based on the established monocyclic peptide, upain-2. It was successfully converted to a bicyclic peptide, without loss of inhibitory properties. The aim was to produce a peptide cyclised by an amide bond with an additional stabilising across-the-ring covalent bond. We expected this bicyclic peptide to exhibit a lower entropic burden upon binding. Two bicyclic peptides were synthesised with affinities similar to that of upain-2, and their binding energetics were evaluated by isothermal titration calorimetry. Indeed, compared to upain-2, the bicyclic peptides showed reduced loss of entropy upon binding to uPA. We also investigated the solution structures of the bicyclic peptide by NMR spectroscopy to map possible conformations. An X-ray structure of the bicyclic-peptide-uPA complex confirmed an interaction similar to that for the previous upain-1/upain-2-uPA complexes. These physical studies of the peptide-protease interactions will aid future designs of bicyclic peptide protease inhibitors.

U2 - 10.1002/cbic.201300335

DO - 10.1002/cbic.201300335

M3 - Journal article

C2 - 24115455

VL - 14

SP - 2179

EP - 2188

JO - ChemBioChem

JF - ChemBioChem

SN - 1439-4227

IS - 16

ER -