Fig 7.

Relationship between secreted HGA-melanin and siderophore activity. As indicated, wild-type strain 130b, lbtA mutant strain NU302, complemented (comp.) lbtA mutant strain NU302, hmgA mutant strain NU326, complemented hmgA mutant strain NU326, lbtA lly double mutant strain NU424, and lly mutant strain NU408 were grown in deferrated CDMP for 24 h, and then the levels of HGA-melanin (A) and relative siderophore activity (B) in cell-free supernatants were determined by measuring the OD₄₀₀ and CAS reactivity, respectively. The data are the means and standard deviations from duplicate samples. All mutant and complemented mutant strains had levels of pigment and siderophore activity that were different from those of the wild type (***, P < 0.001; *, P < 0.05).