Parts exchange: Why molecular machines are like used cars
Leake MC., Wadhams GH., Armitage JP.
Proteins, so small that one billion would fit on a full stop, carry out most of the vital activities in living cells; they drive chemical reactions, transport cargoes, communicate with the outside world and even segregate chromosomes. A novel approach now allows us to monitor single proteins in complicated molecular machines, and it seems that biological components wear out and get replaced just as they do in man-made machines.