Extended Data Fig. 2: Pairwise epistasis across the four-mutation landscape.
From: Cryptic phenotypic variation emerges rapidly during the adaptive evolution of a carbapenemase
(a) Diagram of all mutational trajectories from the ancestral KPC-2 (bottom node). Conventions follow those in Fig. 2a, except that genotypes are numbered 1–16 (rather than labelled by the first letters of mutations) to facilitate the identification of genotypes shown in panel C. Genotype positions match those shown in Fig. 2a. (b) Distribution of epistasis values, calculated as the deviation of each double-mutant fitness from the additive expectation. (c) All possible pairwise interactions. At the top of each panel it is indicated which four genotypes are being considered. For example, the top-left panel compares the single effects of L169P and V240A on the ancestor (genotypes 1, 2 and 3) with their combined effect (genotype 6).
