Figure 9.

FEA1 complements yeast Δ ftr1 mutant and is iron specific. (A) Cells transformed with either the pYES2: vector, or with pYES2:FEA1 were grown in liquid SC-URA galactose (pH 3.5) medium overnight. Cells equivalent to the indicated absorbance values at 600 nm were spotted on SC-URA galactose (pH 3.5) plates. OD for the grown cultures was adjusted to 0.1 and diluted 10 and 100 times. The picture was taken after 72 h incubation at 28 C. (B) Western blot of Flag-tagged FEA1 immuno-detected with anti-FLAG M2-alkaline phosphatase antibody. The Coomassie-blue stained gel is shown below the western blot to show equal loading of the protein. Sensitivity to toxic metal concentrations: Yeast transformed with the pYES2 empty vector (unfilled columns) or the pYES2:FEA1 (filled columns) vector were grown in SC-URA galactose (pH 3.5) for 18 h at 28 C and diluted to 10 cells/mL in fresh SC-URA galactose media (pH 3.5) supplemented with various concentrations of (C) ZnCl₂, (D) CoCl₂, (E) MnSO₄, and (F) CuSO₄. Growth was monitored after 24 h by measuring the absorbance of the culture at 600 nm. Data are means + SE of three replicate experiments. The asterisk (*) indicates statistically significant differences between pYES2 empty vector and pYES2:FEA1 yeast as determined by Student’s t-test, with P < 0.05.