Fig. 5.

Rapid strain improvement by ReSCuES and SCRaMbLE. ReSCuES was applied to identify SCRaMbLEd strains, which are more resistant to higher temperature or acetic acid in strains containing synXII, synIII, or both. Three resistant clones were randomly isolated and tested. a SCRaMbLEd synXII strains were more resistant to high temperature as tested by 10× serial dilution. b Doubling time (mean ± s.d.) of synXII and the SCRaMbLEd strains in YPD medium under 39.5 °C. Three biological replicates were measured, *** is for a P-value < 0.01 using two-tailed student t-test. c Specific growth rate (h⁻¹) (mean ± s.d.) was calculated for synXII and the SCRaMbLEd strains in YPD medium under 39.5 °C. Three biological replicates were measured, *** is for a P-value < 0.01 using two-tailed student t-test. d SCRaMbLEd synXII strains were more resistant to acetic acid (AA) as tested by 10× serial dilution. e The growth capacity of ZLY234 was compared to that of the original synXII strain under different level of stress (0%–0.6% acetic acid, V/V%). Three biological replicates were tested for each strain, using an initial OD₆₀₀ = 0.01. The cell density at each time point and acetic acid concentration was normalized to the original synXII strain (mean ± s.d.). f SCRaMbLEd synIII strains were more resistant to AA as tested by 10× serial dilution. g The growth capacity of LWY804 was compared to that of the original synIII strain under different level of stress (0%–0.45% acetic acid, V/V%). The experiment was performed the same as e. h SCRaMbLEd synIII,synXII strains were more resistant to AA as tested by 10× serial dilution. i The growth of LWY812 was compared to that of the original synIII synXII strain under different level of stress (0–0.46% acetic acid, V/V%). The experiment was performed the same as e