Fig. 3

SID EGYII typing. a Tetrazolium test showing a red brown color of ferrate hydroxamate SID EGYII. b Neilands spectrophotometric assay showing a peak of absorbance between 420 and 450 nm of hydroxamate SID EGYII. Values are averages of three readings ± standard error bars. c Arnow’s test showing absence of red color (no catecholate siderophore)