Fig. 4
Validation and selection of a sensitive element that allows efficient identification of positive mutants. Fluorescence-activated cell sorting results of engineered VB12 producing strains with different production capacity (Sm320-N8, Sm320-L6, and Sm320) were tested separately with eight riboswitches. Fig. a-h exhibited S. meliloti strains carrying different riboswitches, and the genome abbreviations of eight different potential riboswitches were marked in the top left corner of the figures