2FO8

Solution structure of the Trypanosoma cruzi cysteine protease inhibitor chagasin

Summary for 2FO8

• Entry DOI: 10.2210/pdb2fo8/pdb
• Related: 2C34
• NMR Information: BMRB: 6876
• Descriptor: Chagasin (1 entity in total)
• Functional Keywords: chagasin; ig-like domain; cysteine protease inhibitor; trypanosoma cruzi, hydrolase inhibitor
• Biological source: Trypanosoma cruzi
• Total number of polymer chains: 1
• Total formula weight: 12067.41

Authors

Salmon, D.,do Aido-Machado, R.,de Lima, A.A.P.,Scharfstein, J.,Oschkinat, H.,Pires, J.R. (deposition date: 2006-01-13, release date: 2006-04-04, Last modification date: 2024-05-08)

Primary citation

Salmon, D.,do Aido-Machado, R.,Diehl, A.,Leidert, M.,Schmetzer, O.,de Lima, A.A.P.,Scharfstein, J.,Oschkinat, H.,Pires, J.R.
Solution Structure and Backbone Dynamics of the Trypanosoma cruzi Cysteine Protease Inhibitor Chagasin
J.Mol.Biol., 357:1511-1521, 2006

PubMed Abstract: A Trypanosoma cruzi cysteine protease inhibitor, termed chagasin, is the first characterized member of a new family of tight-binding cysteine protease inhibitors identified in several lower eukaryotes and prokaryotes but not present in mammals. In the protozoan parasite T.cruzi, chagasin plays a role in parasite differentiation and in mammalian host cell invasion, due to its ability to modulate the endogenous activity of cruzipain, a lysosomal-like cysteine protease. In the present work, we determined the solution structure of chagasin and studied its backbone dynamics by NMR techniques. Structured as a single immunoglobulin-like domain in solution, chagasin exerts its inhibitory activity on cruzipain through conserved residues placed in three loops in the same side of the structure. One of these three loops, L4, predicted to be of variable length among chagasin homologues, is flexible in solution as determined by measurements of (15)N relaxation. The biological implications of structural homology between chagasin and other members of the immunoglobulin super-family are discussed.

PubMed: 16490204
DOI: 10.1016/j.jmb.2006.01.064

Experimental method

SOLUTION NMR