4NOG image
Entry Detail
PDB ID:
4NOG
Keywords:
Title:
Crystal structure of a putative ornithine aminotransferase from Toxoplasma gondii ME49 in complex with pyrodoxal-5'-phosphate
Biological Source:
Source Organism:
Host Organism:
PDB Version:
Deposition Date:
2013-11-19
Release Date:
2013-12-04
Method Details:
Experimental Method:
Resolution:
1.20 Å
R-Value Free:
0.16
R-Value Work:
0.13
R-Value Observed:
0.13
Space Group:
P 1
Macromolecular Entities
Polymer Type:polypeptide(L)
Description:Putative ornithine aminotransferase, mitochondrial
Chain IDs:A, B
Chain Length:442
Number of Molecules:2
Biological Source:Toxoplasma gondii
Primary Citation
CSGID Solves Structures and Identifies Phenotypes for Five Enzymes in Toxoplasma gondii .
Front Cell Infect Microbiol 8 352 352 (2018)
PMID: 30345257 DOI: 10.3389/fcimb.2018.00352

Abstact

Toxoplasma gondii, an Apicomplexan parasite, causes significant morbidity and mortality, including severe disease in immunocompromised hosts and devastating congenital disease, with no effective treatment for the bradyzoite stage. To address this, we used the Tropical Disease Research database, crystallography, molecular modeling, and antisense to identify and characterize a range of potential therapeutic targets for toxoplasmosis. Phosphoglycerate mutase II (PGMII), nucleoside diphosphate kinase (NDK), ribulose phosphate 3-epimerase (RPE), ribose-5-phosphate isomerase (RPI), and ornithine aminotransferase (OAT) were structurally characterized. Crystallography revealed insights into the overall structure, protein oligomeric states and molecular details of active sites important for ligand recognition. Literature and molecular modeling suggested potential inhibitors and druggability. The targets were further studied with vivoPMO to interrupt enzyme synthesis, identifying the targets as potentially important to parasitic replication and, therefore, of therapeutic interest. Targeted vivoPMO resulted in statistically significant perturbation of parasite replication without concomitant host cell toxicity, consistent with a previous CRISPR/Cas9 screen showing PGM, RPE, and RPI contribute to parasite fitness. PGM, RPE, and RPI have the greatest promise for affecting replication in tachyzoites. These targets are shared between other medically important parasites and may have wider therapeutic potential.

Legend

Protein

Chemical

Disease

Primary Citation of related structures