https://www.sciencedaily.com/releases/2023/03/230316114018.htm > Unraveling the inner workings of a cell requires knowledge of the biochemistry of individual proteins. Measuring tiny changes in their position and shape is the central challenge here. Fluorescence microscopy, in particular super-resolution microscopy (i.e. nanoscopy) has become indispensable in this emerging field. MINFLUX, the recently introduced fluorescence nanoscopy system, has already attained a spatial resolution of one to a few nanometers: the size of small organic molecules. But taking our understanding of molecular cell physiology to the next level requires observations at even higher spatio-temporal resolution. > When Stefan Hell's group first presented MINFLUX in 2016, it had been used to track fluorescently labeled proteins in cells. However, these movements were random, and the tracking had precisions of the order of tens of nanometers. Their study is the first to apply the resolving power of MINFLUX to conformational changes of proteins, specifically the motor protein kinesin-1. To do this, the researchers at the Max Planck Institute for Medical Research developed a new MINFLUX version for tracking single fluorescent molecules.