Fig. 7: Identification of InDels improving the promiscuous arylesterase activity of wtPTE. | Nature Communications

Fig. 7: Identification of InDels improving the promiscuous arylesterase activity of wtPTE.

From: Accessing unexplored regions of sequence space in directed enzyme evolution via insertion/deletion mutagenesis

Fig. 7

a, b Changes in phosphotriesterase (native; PTE) and arylesterase (promiscuous; AE) activities among wtPTE. InDel variants identified upon screening against butyrate (4-NPB; panel a) and hexanoate (2-NH; panel b) esters, respectively. The enzymatic activities for each variant (shown as coloured dots) were measured in cell lysates and are plotted relative to those of wtPTE (grey dot). Data are averages of triplicate values. The dashed diagonal lines (in blue) demarcate the different trade-off regimes. Variants below the diagonal show a strong negative trade-off, with a large detriment to the original PTE activity (specificity ratio >100), as AE activity is improved. Above the diagonal variants with weak trade-off emerge as generalists (specificity ratio <100). c Position of the adaptive InDels in the PTE structure highlighting the frequency of mutations in loops 8 (green), 7 (orange) and 2 (pink). Grey spheres indicate the catalytic Zn2+ ions. Source data are available in the Source data file.

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