The Roles of Molecular Chaperones in the Bacterial Cell
In this chapter, I shall look at the major bacterial molecular chaperones, and summarise the evidence for what we know about their cellular role. Molecular chaperones have risen from obscurity to near superstar status in the last few years, as we have learned that many fundamental aspects of protein function in all cells require the help of other proteins in order to take place. These include the correct folding of proteins as they are translated, their delivery to and passage across membranes, and the repair of proteins which have become inactive because of exposure of the cells to stresses such as an increase in temperature. “Molecular chaperone” is the generic name given to a protein that assists in these processes. The review will be from the point of what is known about what these proteins do in the cell, although I will also describe what is currently understood about the mechanisms by which some of the chaperones work, and how their diverse functions can sometimes be understood in terms of a single mechanism. Finally, I will try to summarise some of the areas where I think key questions about the cellular role of molecular chaperones remain unanswered.
KeywordsMolecular Chaperone Trigger Factor Hydrophobic Side Chain Cellular Role GroEL Protein
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