Fig. 3. (a) In simulation, H102 spontaneously transitions between the crystallographic ‘upright’ conformation (χ₁ ∼ −70°) and a ‘flipped’ conformation (χ₁ ∼ −180°). (b) Metrics used to characterise conformational changes in the simulations: distance between H102 and P115 Cα atoms (turquoise), and the H102 χ₁ torsion angle (grey). (c) Representative simulations of WT and P115A, depicting the metrics illustrated in (b) over the course of the 1 μs simulation. Stars indicate the times that representative snapshots were extracted from the simulation, illustrated in (a). (d) Histograms constructed by aggregating values for each metric for the six WT simulations. (e) Histograms for the six P115A simulations.