Fig. 3.

Involvement of xan cluster metabolites in copper secretion and uptake. (A) Quantification of the zone of activity of CAS assay of xan BGC double mutants. Measurements and error bars are representative of the mean of three replicates and SE, respectively. Letters indicate statistically similar groups via an ANOVA. (B) Growth of the xan BGC double mutants on GMM supplemented with CuSO₄. (Bottom Right) Strain location key. WT, wild type; OE, ΔxanA, OE::xanC;ΔxanA; OE, ΔxanB, OE::xanC;ΔxanB; OE, ΔxanD, OE::xanC;ΔxanD; OE, ΔxanE, OE::xanC;ΔxanE; OE, ΔxanF, OE::xanC;ΔxanF; OE, ΔxanG, OE::xanC;ΔxanG. (C) Cellular copper content of xan cluster mutants grown in liquid shake culture lacking copper or supplemented with 50 μM CuSO₄ as determined by ICP-MS. Error bars represent SEM of three replicates, and statistical analysis was performed using an ANOVA. Statistical groups are designated by a letter.