title: Fragment-based design for the development of N-domain-selective angiotensin-1-converting enzyme inhibitors.
abstract: ACE (angiotensin-1-converting enzyme) is a zinc metallopeptidase that plays a prominent role in blood pressure regulation and electrolyte homeostasis. ACE consists of two homologous domains that despite similarities of sequence and topology display differences in substrate processing and inhibitor binding. The design of inhibitors that selectively inhibit the N-domain (N-selective) could be useful in treating conditions of tissue injury and fibrosis due to build-up of N-domain-specific substrate Ac-SDKP (N-acetyl-Ser-Asp-Lys-Pro). Using a receptor-based SHOP (scaffold hopping) approach with N-selective inhibitor RXP407, a shortlist of scaffolds that consisted of modified RXP407 backbones with novel chemotypes was generated. These scaffolds were selected on the basis of enhanced predicted interaction energies with N-domain residues that differed from their C-domain counterparts. One scaffold was synthesized and inhibitory binding tested using a fluorogenic ACE assay. A molecule incorporating a tetrazole moiety in the P2 position (compound 33RE) displayed potent inhibition (K(i)=11.21±0.74 nM) and was 927-fold more selective for the N-domain than the C-domain. A crystal structure of compound 33RE in complex with the N-domain revealed its mode of binding through aromatic stacking with His388 and a direct hydrogen bond with the hydroxy group of the N-domain specific Tyr369. This work further elucidates the molecular basis for N-domain-selective inhibition and assists in the design of novel N-selective ACE inhibitors that could be employed in treatment of fibrosis disorders.
authors.affiliation: *Institute of Infectious Disease and Molecular Medicine, and Division of Medical Biochemistry, University of Cape Town, Observatory, Cape Town 7935, South Africa.
authors.forename: Ross G
authors.initials: RG
authors.lastname: Douglas
authors.forename: Rajni K
authors.initials: RK
authors.lastname: Sharma
authors.forename: Geoffrey
authors.initials: G
authors.lastname: Masuyer
authors.forename: Lizelle
authors.initials: L
authors.lastname: Lubbe
authors.forename: Ismael
authors.initials: I
authors.lastname: Zamora
authors.forename: K Ravi
authors.initials: KR
authors.lastname: Acharya
authors.forename: Kelly
authors.initials: K
authors.lastname: Chibale
authors.forename: Edward D
authors.initials: ED
authors.lastname: Sturrock
mesh_terms: D000806:Angiotensin-Converting Enzyme Inhibitors / Q000737:chemistry* / Q000494:pharmacology; D001665:Binding Sites / Q000502:physiology; D001794:Blood Pressure / Q000187:drug effects*; D015195:Drug Design; D009842:Oligopeptides / Q000737:chemistry*; D007703:Peptidyl-Dipeptidase A / Q000737:chemistry*; D010721:Phosphinic Acids / Q000737:chemistry*; D011487:Protein Conformation
chemical_list: D000806:Angiotensin-Converting Enzyme Inhibitors; D009842:Oligopeptides; D010721:Phosphinic Acids; C118733:RXP 407; D007703:Peptidyl-Dipeptidase A
references.citation: J Biol Chem. 1991 May 15;266(14):9002-8
references.pmid: 1851160
references.citation: Proc Natl Acad Sci U S A. 1999 Apr 13;96(8):4330-5
references.pmid: 10200262
references.citation: Circ Res. 2003 Jul 25;93(2):148-54
references.pmid: 12805239
references.citation: Acta Crystallogr D Biol Crystallogr. 2004 Aug;60(Pt 8):1355-63
references.pmid: 15272157
references.citation: Protein Expr Purif. 1991 Feb;2(1):1-9
references.pmid: 1668266
references.citation: Biochemistry. 2009 Sep 8;48(35):8405-12
references.pmid: 19658433
references.citation: J Med Chem. 2007 May 31;50(11):2708-17
references.pmid: 17489578
references.citation: J Hypertens. 2011 Feb;29(2):330-8
references.pmid: 21052020
references.citation: Acta Crystallogr D Biol Crystallogr. 2010 Feb;66(Pt 2):125-32
references.pmid: 20124692
references.citation: J Appl Crystallogr. 2007 Aug 1;40(Pt 4):658-674
references.pmid: 19461840
references.citation: J Clin Invest. 1996 Feb 1;97(3):839-44
references.pmid: 8609242
references.citation: Acta Crystallogr D Biol Crystallogr. 1994 Sep 1;50(Pt 5):760-3
references.pmid: 15299374
references.citation: Hypertension. 2007 Mar;49(3):695-703
references.pmid: 17283252
references.citation: Ann N Y Acad Sci. 2005 Nov;1056:160-75
references.pmid: 16387685
references.citation: Hypertension. 2008 Feb;51(2):267-74
references.pmid: 18158355
references.citation: Hypertension. 2003 Dec;42(6):1164-70
references.pmid: 14581293
references.citation: J Mol Biol. 2006 Mar 31;357(3):964-74
references.pmid: 16476442
references.citation: Bioorg Med Chem Lett. 2006 Sep 1;16(17):4612-5
references.pmid: 16784850
references.citation: World J Gastroenterol. 2012 Oct 7;18(37):5283-8
references.pmid: 23066324
references.citation: Biol Chem. 2012 May;393(6):485-93
references.pmid: 22628311
references.citation: Acta Crystallogr D Biol Crystallogr. 1997 May 1;53(Pt 3):240-55
references.pmid: 15299926
references.citation: Cell Tissue Kinet. 1990 Mar;23(2):99-103
references.pmid: 2317837
references.citation: Nucleic Acids Res. 2007 Jul;35(Web Server issue):W375-83
references.pmid: 17452350
references.citation: Am J Pathol. 2010 Sep;177(3):1113-21
references.pmid: 20651228
references.citation: J Biol Chem. 2004 Apr 16;279(16):15946-53
references.pmid: 14757757
references.citation: Lancet. 2002 Jun 15;359(9323):2088-9
references.pmid: 12086766
references.citation: J Chem Inf Model. 2009 Mar;49(3):658-69
references.pmid: 19265417
references.citation: J Intern Med. 2008 Sep;264(3):224-36
references.pmid: 18793332
references.citation: J Mol Biol. 1994 May 20;238(5):777-93
references.pmid: 8182748
references.citation: Circulation. 2005 Oct 18;112(16):2436-45
references.pmid: 16216963
references.citation: Int J Mol Med. 2010 Dec;26(6):795-801
references.pmid: 21042772
references.citation: Hypertension. 2004 Feb;43(2):229-36
references.pmid: 14691195
references.citation: PLoS One. 2012;7(7):e40301
references.pmid: 22802960
references.citation: Life Sci. 2010 Aug 14;87(7-8):232-9
references.pmid: 20624403
references.citation: Hypertension. 1998 Jun;31(6):1299-304
references.pmid: 9622145
references.citation: Acta Crystallogr D Biol Crystallogr. 2004 Dec;60(Pt 12 Pt 1):2126-32
references.pmid: 15572765
references.citation: Protein Eng. 1995 Feb;8(2):127-34
references.pmid: 7630882
references.citation: Am J Physiol Heart Circ Physiol. 2008 Sep;295(3):H1253-H1261
references.pmid: 18641275
references.citation: J Biol Chem. 1995 Feb 24;270(8):3656-61
references.pmid: 7876104
references.citation: Biochem J. 1953 Aug;55(1):170-1
references.pmid: 13093635
references.citation: J Hypertens. 2004 Mar;22(3):593-603
references.pmid: 15076166
references.citation: J Biol Chem. 1993 May 5;268(13):9496-503
references.pmid: 7683654
references.citation: Bioorg Med Chem Lett. 2006 Sep 1;16(17):4616-9
references.pmid: 16784843
references.citation: Curr Med Chem. 2012;19(22):3763-78
references.pmid: 22680930
references.citation: Nature. 2003 Jan 30;421(6922):551-4
references.pmid: 12540854
references.citation: J Biol Chem. 1992 Jul 5;267(19):13398-405
references.pmid: 1320019
references.citation: Lancet. 1998 Jun 6;351(9117):1693-7
references.pmid: 9734886
references.citation: Proc Natl Acad Sci U S A. 1988 Dec;85(24):9386-90
references.pmid: 2849100
references.citation: Nat Rev Drug Discov. 2003 Nov;2(11):891-902
references.pmid: 14668810
references.citation: Hypertension. 2010 Feb;55(2):459-67
references.pmid: 20026760
references.citation: Proc Natl Acad Sci U S A. 1989 Feb;86(3):779-82
references.pmid: 2915977
references.citation: J Biol Chem. 2010 Nov 12;285(46):35685-93
references.pmid: 20826823