Search bioRxiv⌕ Search

Biology subjects

Makumire, S.

Publications and source records attributed to Makumire, S..

2 recordsLinked to original sources

The Computational Analysis of Plasmodium falciparum Heat Shock Proteins Reveals an Interplay with Polyamines

The current drugs available in the market are not effective due to growing numbers of resistance to the causative agent of malaria. There are various Plasmodium parasites, of which Plasmodium falciparum is the main cause of morbidity and mortality reported worldwide. Therefore, there is an urgent need to come up with an innovative and effective treatment for this disease. Polyamines play a major role in the parasites well-being and growth, while heat shock proteins keep the proteomics of the parasite in good shape. In this study, In Silico analysis of the interaction between putrescine, spermidine, spermine, and heat shock proteins was carried out to establish the binding site for drug discovery. Computational tools such as Bioedit, PROCHECK, KNIME Hub, and Schrodinger were used. The results revealed interactions between polyamines and heat shock proteins with glutamine and aspartic acid being common amino acids where interaction occurs between the chaperones and polyamines. MD shows a strong interaction between PfHsp70-1 and putrescine, but the best interaction is observed for PfHsp70-1 and spermidine. Based on these results, a follow-up study will be conducted to establish the synthesis of drugs that will be used as targets for both polyamines and heat shock proteins to eradicate malaria. Authors summaryThe emanation and spread of Plasmodium parasites that are resistant to antimalarial therapy is one of the main problems in the treatment of malaria. This is a result of the Plasmodium parasites ongoing evolution and the creation of novel strategies for surviving drug toxicity. Studies of antimalarial drug development have been focused on polyamine biosynthesis by targeting precursors such as ornithine decarboxylase, adenosylmethionine decarboxylase, and spermidine synthase and protein-protein interactions between Plasmodium falciparum chaperones spotting out Hsp90, Hsp70, and Hsp40 as potential targets with little attention being paid to the interaction between polyamines and molecular chaperones. Therefore, to study these interactions the binding sites of all 3D structures were identified using SiteMap, and a docking was performed using the Schrodinger software with OPLS4 force field and XP.

bioinformatics↗

Biophysical analysis of Plasmodium falciparum Hsp70-Hsp90 organizing protein (PfHop) reveals a monomer that is characterised by folded segments connected by flexible linkers

Plasmodium falciparum causes the most lethal form of malaria. The cooperation of heat shock protein (Hsp) 70 and 90 is important for folding of a select number of cellular proteins that are crucial for cyto-protection and development of the parasites. Hsp70 and Hsp90 are brought into a functional complex that allows substrate exchange by stress inducible protein 1 (STI1), also known as Hsp70-Hsp90 organizing protein (Hop). P. falciparum Hop (PfHop) co-localises and occurs in complex with the parasite cytosolic chaperones, PfHsp70-1 and PfHsp90. Here, we characterised the structure of recombinant PfHop using synchrotron radiation circular dichroism (SRCD) and small-angle X-ray scattering. Structurally, PfHop is a monomeric, elongated but folded protein, in agreement with its predicted TPR domain structure. Using SRCD, we established that PfHop is unstable at temperatures higher than 40 {degrees}C. This suggests that PfHop is less stable at elevated temperatures compared to its functional partner, PfHsp70-1, that is reportedly stable at temperatures as high as 80 {degrees}C. These findings contribute towards our understanding of the role of the Hop-mediated functional partnership between Hsp70 and Hsp90.

biochemistry↗