Research Repository

Plasmodium falciparum heat shock protein 70 is able to suppress the thermosensitivity of an Escherichia coli DnaK mutant strain

Shonhai, A, Boshoff, A and Blatch, Gregory L (2005) Plasmodium falciparum heat shock protein 70 is able to suppress the thermosensitivity of an Escherichia coli DnaK mutant strain. Molecular Genetics and Genomics, 274 (1). pp. 70-78. ISSN 1617-4615

Full text for this resource is not available from the Research Repository.

Abstract

Heat shock protein 70 (Hsp70) and heat shock protein 40 (Hsp40) are molecular chaperones that ensure that the proteins of the cell are properly folded and functional under both normal and stressful conditions. The malaria parasite Plasmodium falciparum is known to overproduce a heat shock protein 70 (PfHsp70) in response to thermal stress; however, the in vivo function of this protein still needs to be explored. Using in vivo complementation assays, we found that PfHsp70 was able to suppress the thermosensitivity of an Escherichia coli dnaK756 strain, but not that of the corresponding deletion strain (DeltadnaK52) or dnaK103 strain, which produces a truncated DnaK. Constructs were generated that encoded the ATPase domain of PfHsp70 fused to the substrate-binding domain (SBD) of E. coli DnaK (referred to as PfK), and the ATPase domain of E. coli DnaK coupled to the SBD of PfHsp70 (KPf). PfK was unable to suppress the thermosensitivity of any of the E. coli strains. In contrast, KPf was able to suppress the thermosensitivity in the E. coli dnaK756 strain. We also identified two key amino acid residues (V401 and Q402) in the linker region between the ATPase domain and SBD that are essential for the in vivo function of PfHsp70. This is the first example of an Hsp70 from a eukaryotic parasite that can suppress thermosensitivity in a prokaryotic system. In addition, our results also suggest that interdomain communication is critical for the function of the PfHsp70 and PfHsp70-DnaK chimeras. We discuss the implications of these data for the mechanism of action of the Hsp70-Hsp40 chaperone machinery.

Item Type: Article
Additional Information:

Online ISSN: 1617-4623

Uncontrolled Keywords: ResPubID22213. E. coli DnaK, PfHsp70, complementation, domain swapping, interdomain communication, Plasmodium falciparum, heat shock protein, proteins, Escherichia coli, DNA, ATPase
Subjects: Faculty/School/Research Centre/Department > School of Biomedical and Health Sciences
FOR Classification > 0601 Biochemistry and Cell Biology
FOR Classification > 0604 Genetics
Depositing User: VUIR
Date Deposited: 12 Jan 2012 03:50
Last Modified: 01 Dec 2014 01:01
URI: http://vuir.vu.edu.au/id/eprint/8158
DOI: https://doi.org/10.1007/s00438-005-1150-9
ePrint Statistics: View download statistics for this item
Citations in Scopus: 39 - View on Scopus

Repository staff only

View Item View Item

Search Google Scholar