4Y6M image
Entry Detail
PDB ID:
4Y6M
Keywords:
Title:
Structure of plasmepsin II from Plasmodium falciparum complexed with inhibitor PG418
Biological Source:
Source Organism:
Host Organism:
PDB Version:
Deposition Date:
2015-02-13
Release Date:
2015-12-09
Method Details:
Experimental Method:
Resolution:
2.27 Å
R-Value Free:
0.21
R-Value Work:
0.17
R-Value Observed:
0.17
Space Group:
P 21 21 21
Macromolecular Entities
Polymer Type:polypeptide(L)
Description:Plasmepsin-2
Chain IDs:A, B, C
Chain Length:329
Number of Molecules:3
Biological Source:Plasmodium falciparum
Primary Citation
Structures of plasmepsin II from Plasmodium falciparum in complex with two hydroxyethylamine-based inhibitors.
Acta Crystallogr.,Sect.F 71 1531 1539 (2015)
PMID: 26625296 DOI: 10.1107/S2053230X15022049

Abstact

Plasmepsin II (PMII) is one of the ten plasmepsins (PMs) identified in the genome of Plasmodium falciparum, the causative agent of the most severe and deadliest form of malaria. Owing to the emergence of P. falciparum strains that are resistant to current antimalarial agents such as chloroquine and sulfadoxine/pyrimethamine, there is a constant pressure to find new and lasting chemotherapeutic drug therapies. Previously, the crystal structure of PMII in complex with NU655, a potent antimalarial hydroxyethylamine-based inhibitor, and the design of new compounds based on it have been reported. In the current study, two of these newly designed hydroxyethylamine-based inhibitors, PG418 and PG394, were cocrystallized with PMII and their structures were solved, analyzed and compared with that of the PMII-NU655 complex. Structural analysis of the PMII-PG418 complex revealed that the flap loop can adopt a fully closed conformation, stabilized by interactions with the inhibitor, and a fully open conformation, causing an overall expansion in the active-site cavity, which in turn causes unstable binding of the inhibitor. PG418 also stabilizes the flexible loop Gln275-Met286 of another monomer in the asymmetric unit of PMII, which is disordered in the PMII-NU655 complex structure. The crystal structure of PMII in complex with the inhibitor PG418 demonstrates the conformational flexibility of the active-site cavity of the plasmepsins. The interactions of the different moieties in the P1' position of PG418 and PG394 with Thr217 have to be taken into account in the design of new potent plasmepsin inhibitors.

Legend

Protein

Chemical

Disease

Primary Citation of related structures