Overexpression, purification and characterisation of the Plasmodium falciparum Hsp70-z (PfHsp70-z) protein.

Date
2015-06-17
Authors
Zininga, T.
Hoppe, H.C.
Prinsloo.E.
Dirr, H.W.
Shonhai, A.
Achilonu, I.
Journal Title
Journal ISSN
Volume Title
Publisher
Public Library of Science.
Abstract
Six Hsp70-like genes are represented on the genome of Plasmodium falciparum. Of these two occur i0n the cytosol: P. falciparum Hsp70-z (PfHsp70-z) and PfHsp70-1. PfHsp70-1 is a well characterised canonical Hsp70 that facilitates protein quality control and is crucial for the development of malaria parasites. There is very little known about PfHsp70-z. However, PfHsp70-z is known to be essential and is implicated in suppressing aggregation of asparagine-rich proteins of P. falciparum. In addition, its expression at the clinical stage of malaria correlates with disease prognosis. Based on structural evidence PfHsp70-z belongs to the Hsp110 family of proteins. Since Hsp110 proteins have been described as nucleotide exchange factors (NEFs) of their canonical Hsp70 counterparts, it has been speculated that PfHsp70-z may serve as a NEF of PfHsp70-1. In the current study, P. falciparum cells cultured in vitro were subjected to heat stress, triggering the enhanced expression of PfHsp70-z. Biochemical assays conducted using recombinant PfHsp70-z protein demonstrated that the protein is heat stable and possesses ATPase activity. Furthermore, we observed that PfHsp70-z is capable of self-association. The structural-functional features of PfHsp70-z provide further evidence for its role as a chaperone and possible nucleotide exchange factor of PfHsp70-1.
Description
Keywords
adenosine triphosphatase;, chaperone;, heat shock protein 70;, controlled study;, cross reaction;, enzyme activity;, gene;, gene overexpression;, heat stress;, heat stress;, Hsp70 gene;, malaria; nonhuman;, Plasmodium falciparum;, protein aggregation;, protein expression;, protein purification;, protein secondary structure;, structure analysis;, temperature;, upregulation, Plasmodium falciparum;
Citation
Zininga, T. et al. 2015. Overexpression, purification and characterisation of the Plasmodium falciparum Hsp70-z (PfHsp70-z) protein. PLOS ONE 10(6):e0129445