Figure 7
20 000 particles were randomly chosen from the final 3D refinement of the full data sets and re-extracted from individual frames for 3D reconstruction. In data sets acquired from apoferritin (ApoF) in cubic ice (left) the resolution of the reconstructions using only the first frame (1.3 e Å−2) were better than those of vitrified specimens (right). The overall trend in the reconstructions from apoferritin in cubic ice was a decrease in resolution with increasing fluence, as expected owing to accumulating radiation damage. With apoferritin in vitreous water, the highest resolution single-frame reconstruction was obtained with the fourth frame (4.6 e Å−2), at which point the initial burst of beam-induced movement had subsided. For vitrified samples, the resolution of the first-frame reconstruction (1.15–1.23 e Å−2) was consistently lower than for any of the first ten frames owing to the large initial beam-induced movement. |