Before revision:  In the presence of ionophores and uncouplers the fastest subunit rotation speeds measured in single reconstituted FoF1-ATP synthases were 180 full rounds per second , i. e. much faster than measured by biochemical ensemble averaging, but not as fast as the maximum rotational speed reported previoulsy for isolated single F1 fragments without coupling to the membrane-embedded Fo domain of the enzyme .
After revision:  In the presence of ionophores and uncouplers the fastest subunit rotation speeds measured in single reconstituted FoF1-ATP synthases were 180 full rounds per second , i. e. much faster than measured by biochemical ensemble averaging, but not as fast as the maximum rotational speed reported previoulsy for isolated single F1 fragments without coupling to the membrane-embedded Fo complex. Further application of ABEL trap measurements should help resolve the mechanistic causes of such fluctuating rates of subunit rotation .