Florence Lisa Muzenda, Melissa Louise Stofberg, Wendy Mthembu, Ikechukwu Achilonu, Erick Strauss, Tawanda Zininga
{"title":"Characterization and Inhibition of the Chaperone Function of Plasmodium falciparum Glucose-Regulated Protein 94 kDa (Pf Grp94).","authors":"Florence Lisa Muzenda, Melissa Louise Stofberg, Wendy Mthembu, Ikechukwu Achilonu, Erick Strauss, Tawanda Zininga","doi":"10.1002/prot.26779","DOIUrl":null,"url":null,"abstract":"<p><p>Plasmodium falciparum expresses four heat shock protein 90 (Hsp90) members. Among these, one, glucose-regulated protein 94 (PfGrp94), is localized in the endoplasmic reticulum (ER). Both the cytosolic and ER-based Hsp90s are essential for parasite survival under all growth conditions. The cytosolic version has been extensively studied and has been targeted in several efforts through the repurposing of anticancer therapeutics as antimalarial drugs. However, PfGrp94 has not been fully characterized and some of its functions related to the ER stress response are not fully understood. Structural analysis of the recombinant full-length PfGrp94 protein showed a predominantly α-helical secondary structure and its thermal resilience was modulated by 5'-N-ethyl-carboxamide-adenosine (NECA) and nucleotides ATP/ADP. PfGrp94 exhibits ATPase activity and suppressed heat-induced aggregation of a model substrate, malate dehydrogenase, in a nucleotide-dependent manner. However, these PfGrp94 chaperone functions were abrogated by NECA. Molecular docking and molecular dynamics (MD) simulations showed that NECA interacted with unique residues on PfGrp94, which could be potentially exploited for selective drug design. Finally, using parasites maintained at the red blood stage, NECA exhibited moderate antiplasmodial activity (IC<sub>50</sub> of 4.3, 7.4, and 10.0 μM) against three different P. falciparum strains. Findings from this study provide the first direct evidence for the correlation between in silico, biochemical, and in vitro data toward utilizing the ER-based chaperone, PfGrp94, as a drug target against the malaria parasites.</p>","PeriodicalId":56271,"journal":{"name":"Proteins-Structure Function and Bioinformatics","volume":" ","pages":"957-971"},"PeriodicalIF":3.2000,"publicationDate":"2025-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11968560/pdf/","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Proteins-Structure Function and Bioinformatics","FirstCategoryId":"99","ListUrlMain":"https://doi.org/10.1002/prot.26779","RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"2024/12/13 0:00:00","PubModel":"Epub","JCR":"Q2","JCRName":"BIOCHEMISTRY & MOLECULAR BIOLOGY","Score":null,"Total":0}
引用次数: 0
Abstract
Plasmodium falciparum expresses four heat shock protein 90 (Hsp90) members. Among these, one, glucose-regulated protein 94 (PfGrp94), is localized in the endoplasmic reticulum (ER). Both the cytosolic and ER-based Hsp90s are essential for parasite survival under all growth conditions. The cytosolic version has been extensively studied and has been targeted in several efforts through the repurposing of anticancer therapeutics as antimalarial drugs. However, PfGrp94 has not been fully characterized and some of its functions related to the ER stress response are not fully understood. Structural analysis of the recombinant full-length PfGrp94 protein showed a predominantly α-helical secondary structure and its thermal resilience was modulated by 5'-N-ethyl-carboxamide-adenosine (NECA) and nucleotides ATP/ADP. PfGrp94 exhibits ATPase activity and suppressed heat-induced aggregation of a model substrate, malate dehydrogenase, in a nucleotide-dependent manner. However, these PfGrp94 chaperone functions were abrogated by NECA. Molecular docking and molecular dynamics (MD) simulations showed that NECA interacted with unique residues on PfGrp94, which could be potentially exploited for selective drug design. Finally, using parasites maintained at the red blood stage, NECA exhibited moderate antiplasmodial activity (IC50 of 4.3, 7.4, and 10.0 μM) against three different P. falciparum strains. Findings from this study provide the first direct evidence for the correlation between in silico, biochemical, and in vitro data toward utilizing the ER-based chaperone, PfGrp94, as a drug target against the malaria parasites.
期刊介绍:
PROTEINS : Structure, Function, and Bioinformatics publishes original reports of significant experimental and analytic research in all areas of protein research: structure, function, computation, genetics, and design. The journal encourages reports that present new experimental or computational approaches for interpreting and understanding data from biophysical chemistry, structural studies of proteins and macromolecular assemblies, alterations of protein structure and function engineered through techniques of molecular biology and genetics, functional analyses under physiologic conditions, as well as the interactions of proteins with receptors, nucleic acids, or other specific ligands or substrates. Research in protein and peptide biochemistry directed toward synthesizing or characterizing molecules that simulate aspects of the activity of proteins, or that act as inhibitors of protein function, is also within the scope of PROTEINS. In addition to full-length reports, short communications (usually not more than 4 printed pages) and prediction reports are welcome. Reviews are typically by invitation; authors are encouraged to submit proposed topics for consideration.