Fig. 4: Overview of structures in the assembly reactions.

a,b, Pie charts show the relative abundance of the structures determined for each replicate (numbered 1–5 inside the pie charts) of the PHF reaction (a) and the CTE reaction (b). Relative abundances were calculated on the basis of the distribution of particle counts from cryo-EM micrographs of each replicate. Main-chain traces for atomic structures are shown in the same colours as the pie chart segments for each reaction. Grey segments represent filaments for which no structures were solved. Structures that were solved at resolutions insufficient for atomic modelling are shown as thresholded densities and are indicated with asterisks. Structures and pie chart central circles are coloured per time point (120 min in purple; 180 min in blue; 240 min in green; 300 min in yellow; 360 min in orange and 720 min in red). All structures shown are unique and coloured according to the time point at which they are most abundant, averaged across all replicates. More abundant structures (assessed by maximal percentage across all replicates and time points) are closer to the time axis, whereas less abundant ones are further away. Details of all datasets and structures, including pie charts of additional replicates and time points, are shown in Supplementary Figs. 1–48.