Fig. 3: Identified G. oxydans gene disruptions raised REE-bioleaching by up to 111% or lowered it by 97%.
From: Direct genome-scale screening of Gluconobacter oxydans B58 for rare earth element bioleaching
Direct measurement of bioleaching extraction was performed on disruption mutants of interest following bioleaching experiments with synthetic monazite, using ICP-MS analysis. REE extractions were analyzed with pairwise comparisons among disruption mutants (n = 3) and pWT (n = 3). Levels of extraction significantly different from pWT are labeled with asterisks (*p < 0.05; **p < 0.01; ***p < 0.001, ****p < 0.0001) or “ns” if p > 0.05, denoting statistical significance after Bonferroni-corrected t-tests (N = 12). Blue squares indicate the mean extraction for each mutant, the center line denotes the median, boxes show the upper and lower quartiles, and whiskers extend to the range of data points within 1.5 times the interquartile range. Strains δGO_1162, δGO_1113, and δGO_1968 did not show statistically significant changes in extraction compared to pWT. Only one disruption mutant, δGO_1096, decreased bioleaching, demonstrating a 97% reduction in extraction. Current best-performing engineered strains, G. oxydans ΔpstS (single knockout) and G. oxydans P112:mgdh, ΔpstS (up-regulation and knockout), were included to contrast the extractions of the tested disruption mutants. Significant changes in extraction efficiency compared against the WT strain can be found in Supplementary Fig. 1.
