Fig. 5: Growth-improving mutations within the target.

a Distribution of fitness effects for the growth-associated fitness measures in M9 minimal media + Glucose for all (blue) and synonymous mutations (orange). b Residue-wise distribution of growth-associated fitness for beneficial variant (blue dots), synonymous variants (gray dots), and deleterious variants (red dots) with the cut-off for beneficial fitness score (top gray line) and deleterious fitness score (bottom gray line). c Residue-level mean growth-associated fitness heatmap on the target structure, with increasing fitness represented as a gradient from red to blue. d Residues with high mean growth-associated fitness (green sticks), and highly conserved and functionally important Bridge Helix (BH) residues (orange sticks). (Left) BH (bridge helix) residues with charged side chains (blue sticks) and proximal target residues with high growth-associated fitness means (red sticks). e (Right) A bar plot (blue) of mean growth-associated fitness for substitutions to amino acids with positively charged (blue) and negatively charged (red) sidechains respectively. Within each box, the horizontal black lines represent median values, lower and upper bounds correspond to the 25th and 75th percentile, and the whiskers extend to the extreme values within the 1.5× interquartile range. The top and bottom dashed lines represent the cutoff for beneficial and deleterious fitness scores respectively. There were 6, 2, 2, 28, 34, 10, and 4 independent observations for each variant left to right in the plot. An observation represents an independent fitness measurement of a synonymous variant of the focal mutation in two biological replicates (Supplementary Note 1). f Correlation of growth-associated fitness with the enrichment for CR703 resistance for target mutations. The dashed vertical and horizontal lines represent the cut-off for beneficial growth-associated fitness and CBR703 resistance respectively. g Residues with greater than five CBR703 resistant mutations (all spheres) and ones with high growth-associated mean fitness (green spheres). h Residues with high growth-associated fitness (green sticks) with red lines connecting two residues with significant positive epistatic interaction (Supplementary Fig. 4 and Supplementary Note 2). Source data are provided as a Source Data file.