skip to main content

Title: The Clp Chaperones and Proteases of the Human Malaria Parasite Plasmodium falciparum

The Clp chaperones and proteases play an important role in protein homeostasis in the cell. They are highly conserved across prokaryotes and found also in the mitochondria of eukaryotes and the chloroplasts of plants. They function mainly in the disaggregation, unfolding and degradation of native as well as misfolded proteins. Here, we provide a comprehensive analysis of the Clp chaperones and proteases in the human malaria parasite Plasmodium falciparum. The parasite contains four Clp ATPases, which we term PfClpB1, PfClpB2, PfClpC and PfClpM. One PfClpP, the proteolytic subunit, and one PfClpR, which is an inactive version of the protease, were also identified. Expression of all Clp chaperones and proteases was confirmed in blood-stage parasites. The proteins were localized to the apicoplast, a non-photosynthetic organelle that accommodates several important metabolic pathways in P. falciparum, with the exception of PfClpB2 (also known as Hsp101), which was found in the parasitophorous vacuole. Both PfClpP and PfClpR form mostly homoheptameric rings as observed by size-exclusion chromatography, analytical ultracentrifugation and electron microscopy. The X-ray structure of PfClpP showed the protein as a compacted tetradecamer similar to that observed for Streptococcus pneumoniae and Mycobacterium tuberculosis ClpPs. Our data suggest the presence of a ClpCRP complex inmore » the apicoplast of P. falciparum.« less
Authors:
; ; ; ; ; ; ; ; ; ; ; ;  [1] ;  [2] ;  [2] ;  [2] ;  [2]
  1. (McMaster U.)
  2. (
Publication Date:
OSTI Identifier:
1037475
Resource Type:
Journal Article
Resource Relation:
Journal Name: J. Mol. Biol.; Journal Volume: 404; Journal Issue: (3) ; 12, 2010
Research Org:
Advanced Photon Source (APS), Argonne National Laboratory (ANL), Argonne, IL (US)
Sponsoring Org:
FOREIGN
Country of Publication:
United States
Language:
ENGLISH
Subject:
59 BASIC BIOLOGICAL SCIENCES; 60 APPLIED LIFE SCIENCES; BIOLOGICAL PATHWAYS; CELL CONSTITUENTS; CHLOROPLASTS; CHROMATOGRAPHY; ELECTRON MICROSCOPY; HOMEOSTASIS; MALARIA; MITOCHONDRIA; MYCOBACTERIUM TUBERCULOSIS; PARASITES; PLASMODIUM; PROTEINS; STREPTOCOCCUS; ULTRACENTRIFUGATION