Chaperone Co-Chaperone Interactions in Malarial Infection
I. Onyesom¹* and I. C. Onyebuchi²¹Department of Medical Biochemistry, Delta State University, Abraka Nigeria.
²Department of Biochemistry, Anambra State University, Uli Nigeria.
Abstract: The fact that a protein can by itself find its appropriate folded state in vitro does not necessarily mean that the same event occurs in vivo. There is evidence that all kinds of cells contain proteins known as chaperones which help in the proper assembly of protein structure. Molecular chaperones are essential proteins that bind to unfolded and partially folded polypeptide chains to prevent their improper association of exposed hydrophobic segments that might lead to non-native fold as well as polypeptide aggregation and precipitation. Their function is to “chaperone” polypeptide chains by apparently assisting them to fold; preventing proteins destined for membranes or for export through the membrane from folding instead of being inserted into the cell membrane; protect polypeptide chains from aggregation; induce misfolded proteins to fold to their normal conformations. There are three classes of molecular chaperones – the Hsp 70 family of 70kDa proteins which function as monomers; the chaperonins which are large multisubunit proteins; the Hsp 90 proteins which mainly participate in folding proteins involved in signal transduction such as steroid receptors. Co- chaperones are proteins that aid chaperones in carrying out their numerous functions. Interaction between these proteins (chaperones and co-chaperones) in the assembly of protein structure generally proceed via their binding to an unfolded or aggregated polypeptide’s exposed hydrophobic surfaces and subsequently releasing it, often repeatedly in a manner that facilitates its proper folding. Most molecular chaperones are ATPases and the favourable energy of ATP hydrolysis drives the chaperone’s bind-and-release cycle. Understanding of chaperone co-chaperone interactions in malarial infection is becoming useful in identifying potential targets for the development of novel anti-malarial drugs.
Keywords: Chaperone; malaria; polypeptide; cochaperones Back to TOC