AbstractAll living organisms have evolved to contain a set of proteins with variable physical and chemical properties. Efforts in the field of structural biology have contributed to uncovering the shape and the variability of each component. A set of experimental coordinates for a given protein can be used to define the “morphness/unmorphness”. Here we show the results of global analysis of more than a thousand E. coli proteins, demonstrating that it would be a comprehensive method of understanding the evolved repertoire in an organism. By collecting “UnMorphness Factor” (UMF) determined for each of the proteins, the lowest and the highest boundaries of the experimentally observable structural variation are understood. The distribution of UMFs obtained for an organism is expected to represent how rigid and flexible components are balanced. The present analysis extends to evaluate the growing data from single particle cryo-electron microscopy, providing valuable information on effective interpretation to structural changes of proteins and the supramolecular complexes. The data and the method presented here also conform to FAIR data principles, having potential significance to advance the field of structural and molecular cell biology.