Designed Parasite-Selective Rhomboid Inhibitors Block Invasion and Clear Blood-Stage Malaria

0532443 - ÚOCHB 2021 RIV US eng J - Journal Article
Gandhi, S. - Baker, R. P. - Cho, S. - Stanchev, Stancho - Stříšovský, Kvido - Urban, S.
Designed Parasite-Selective Rhomboid Inhibitors Block Invasion and Clear Blood-Stage Malaria.
Cell Chemical Biology. Roč. 27, č. 11 (2020), s. 1410-1424. ISSN 2451-9448. E-ISSN 2451-9448
R&D Projects: GA ČR(CZ) GA18-09556S
Institutional support: RVO:61388963
Keywords : malaria * Plasmodium * regulated intramembrane proteolysis * rhomboid protease * serine protease * presenilin * site-2 protease * Ras-converting enzyme * apicomplexan parasites * Toxoplasma
OECD category: Biochemistry and molecular biology
Impact factor: 8.116, year: 2020
Method of publishing: Limited access
https://doi.org/10.1016/j.chembiol.2020.08.011

Rhomboid intramembrane proteases regulate pathophysiological processes, but their targeting in a disease context has never been achieved. We decoded the atypical substrate specificity of malaria rhomboid PfROM4, but found, unexpectedly, that it results from “steric exclusion”: PfROM4 and canonical rhomboid proteases cannot cleave each other's substrates due to reciprocal juxtamembrane steric clashes. Instead, we engineered an optimal sequence that enhanced proteolysis >10-fold, and solved high-resolution structures to discover that boronates enhance inhibition >100-fold. A peptide boronate modeled on our “super-substrate” carrying one “steric-excluding” residue inhibited PfROM4 but not human rhomboid proteolysis. We further screened a library to discover an orthogonal alpha-ketoamide that potently inhibited PfROM4 but not human rhomboid proteolysis. Despite the membrane-immersed target and rapid invasion, ultrastructural analysis revealed that single-dosing blood-stage malaria cultures blocked host-cell invasion and cleared parasitemia. These observations establish a strategy for designing parasite-selective rhomboid inhibitors and expose a druggable dependence on rhomboid proteolysis in non-motile parasites.
Permanent Link: http://hdl.handle.net/11104/0311007