1U9Q

Crystal structure of cruzain bound to an alpha-ketoester

Summary for 1U9Q

• Entry DOI: 10.2210/pdb1u9q/pdb
• Related: 1F29 1F2A 1F2B 1F2C 1ME3 1ME4
• Descriptor: cruzipain, [1-(1-METHYL-4,5-DIOXO-PENT-2-ENYLCARBAMOYL)-2-PHENYL-ETHYL]-CARBAMIC ACID BENZYL ESTER (3 entities in total)
• Functional Keywords: clan-ca cysteine protease; covalent inhibitor, hydrolase
• Biological source: Trypanosoma cruzi
• Total number of polymer chains: 1
• Total formula weight: 23123.58

Authors

Lange, M.,Weston, S.G.,Cheng, H.,Culliane, M.,Fiorey, M.M.,Grisostomi, C.,Hardy, L.W.,Hartstough, D.S.,Pallai, P.V.,Tilton, R.F.,Baldino, C.M.,Brinen, L.S.,Engel, J.C.,Choe, Y.,Price, M.S.,Craik, C.S. (deposition date: 2004-08-10, release date: 2005-03-29, Last modification date: 2024-10-30)

Primary citation

Choe, Y.,Brinen, L.S.,Price, M.S.,Engel, J.C.,Lange, M.,Grisostomi, C.,Weston, S.G.,Pallai, P.V.,Cheng, H.,Hardy, L.W.,Hartsough, D.S.,McMakin, M.,Tilton, R.F.,Baldino, C.M.,Craik, C.S.
Development of alpha-keto-based inhibitors of cruzain, a cysteine protease implicated in Chagas disease
Bioorg.Med.Chem., 13:2141-2156, 2005

PubMed Abstract: Trypanosoma cruzi, a protozoan parasite, is the causative agent of Chagas disease, a major cause of cardiovascular disease in many Latin American countries. There is an urgent need to develop an improved therapy due to the toxicity of existing drugs and emerging drug resistance. Cruzain, the primary cysteine protease of T. cruzi, is essential for the survival of the parasite in host cells and therefore is an important target for the development of inhibitors as potential therapeutics. A novel series of alpha-ketoamide-, alpha-ketoacid-, alpha-ketoester-, and aldehyde-based inhibitors of cruzain has been developed. The inhibitors were identified by screening protease targeted small molecule libraries and systematically optimizing the P1, P2, P3, and P1' residues using specific structure-guided methods. A total of 20 compounds displayed picomolar potency in in vitro assays and three inhibitors representing different alpha-keto-based inhibitor scaffolds demonstrated anti-trypanosomal activity in cell culture. A 2.3A crystallographic structure of cruzain bound with one of the alpha-ketoester analogs is also reported. The structure and kinetic assay data illustrate the covalent binding, reversible inhibition mechanism of the inhibitor. Information on the compounds reported here will be useful in the development of new lead compounds as potential therapeutic agents for the treatment of Chagas disease and as biological probes to study the role that cruzain plays in the pathology. This study also demonstrates the validity of structure-guided approaches to focused library design and lead compound optimization.

PubMed: 15727867
DOI: 10.1016/j.bmc.2004.12.053

Experimental method

X-RAY DIFFRACTION (2.3 Å)