A Small Force Remodels a Large Protein to Unleash Its Deadly Potential

摘要

Poisons are powerful weapons, but they carry an inherent risk for those who wield them—becoming one's own victim. E. coli bacteria, which manufacture a DNA-destroying enzyme used to kill other cells, have solved this problem by blocking part of the enzyme's surface with a second protein while it awaits delivery. The two bind so tightly, in fact, that researchers have had trouble figuring out how the cell manages to ever separate them when the time comes. In a new study in PLOS Biology, Oliver Farrance, David Brockwell, and colleagues show that a small applied force can greatly reduce the underlying stability of the complex and vastly increase the dissociation rate.