Figure 8
Figure 8. Superposition of Sia24 predictive and
crystallographic models. The structure of Sia24 (dark blue) was solved
with initial phase determination by molecular replacement using a model
generated by AlphaFold2 (yellow).
Given the initial results for both Phyre2 and ensembled low-homology
models in molecular replacement, a solution for Sia24 without AlphaFold2
would have likely been eventually determined. However, the greatly
improved accuracy of the AlphaFold2 models, with all side chains and
flexible loops in place, is undeniable. Sia24 exhibits roughly 20%
sequence homology with previously known structures, which in most cases
is at the threshold of likely success with molecular replacement for
most targets. AlphaFold2 was able to use information from known
structures in a novel way compared to previous algorithms, and provide
an effective solution where the alternatives struggled.