Molecular motors are efficient nanoscale machines destined to make any human designed engine look clumsy. F1-ATPase is such a machine - so powerful that a spoonful of it could produce as much torque as your car's engine. As part of the enzyme ATP synthase, the protein can work as an engine but also operate in reverse as a generator. In the latter mode it is responsible for the synthesis of the energy-rich molecule ATP that serves as fuel driving many processes in biological cells. It can also convert the energy stored in ATP into mechanical rotation. A recent study suggests that the analogy to a car's engine goes even further! A quantum chemical description of the reaction of ATP combined with a simulation of the protein revealed that an amino acid side group of the protein, called the "arginine finger", controls the progression of the catalytic event, much like a spark plug controls the combustion process in a car engine. The very extensive simulation made use of a powerful computer, the Jonas Cluster at the Pittsburgh Supercomputing Center. The investigation is yet another example for the important role of computational biology unraveling the secret behind the function of the machinery of living cells (more).