1CI1

CRYSTAL STRUCTURE OF TRIOSEPHOSPHATE ISOMERASE FROM TRYPANOSOMA CRUZI IN HEXANE

Summary for 1CI1

• Entry DOI: 10.2210/pdb1ci1/pdb
• Descriptor: PROTEIN (TRIOSEPHOSPHATE ISOMERASE), HEXANE (3 entities in total)
• Functional Keywords: triosephosphate isomerase, trypanosoma cruzi, organic solvent, hexane, oligomeric protein
• Biological source: Trypanosoma cruzi
• Total number of polymer chains: 2
• Total formula weight: 54979.40

Authors

Gao, X.-G.,Maldondo, E.,Perez-Montfort, R.,De Gomez-Puyou, M.T.,Gomez-Puyou, A.,Rodriguez-Romero, A. (deposition date: 1999-04-06, release date: 1999-09-01, Last modification date: 2023-08-09)

Primary citation

Gao, X.G.,Maldonado, E.,Perez-Montfort, R.,Garza-Ramos, G.,de Gomez-Puyou, M.T.,Gomez-Puyou, A.,Rodriguez-Romero, A.
Crystal structure of triosephosphate isomerase from Trypanosoma cruzi in hexane.
Proc.Natl.Acad.Sci.USA, 96:10062-10067, 1999

PubMed Abstract: To gain insight into the mechanisms of enzyme catalysis in organic solvents, the x-ray structure of some monomeric enzymes in organic solvents was determined. However, it remained to be explored whether the structure of oligomeric proteins is also amenable to such analysis. The field acquired new perspectives when it was proposed that the x-ray structure of enzymes in nonaqueous media could reveal binding sites for organic solvents that in principle could represent the starting point for drug design. Here, a crystal of the dimeric enzyme triosephosphate isomerase from the pathogenic parasite Trypanosoma cruzi was soaked and diffracted in hexane and its structure solved at 2-A resolution. Its overall structure and the dimer interface were not altered by hexane. However, there were differences in the orientation of the side chains of several amino acids, including that of the catalytic Glu-168 in one of the monomers. No hexane molecules were detected in the active site or in the dimer interface. However, three hexane molecules were identified on the surface of the protein at sites, which in the native crystal did not have water molecules. The number of water molecules in the hexane structure was higher than in the native crystal. Two hexanes localized at <4 A from residues that form the dimer interface; they were in close proximity to a site that has been considered a potential target for drug design.

PubMed: 10468562
DOI: 10.1073/pnas.96.18.10062

Experimental method

X-RAY DIFFRACTION (2 Å)