TABLE 1.

Bacterial and yeast strains used in this study

Strain	Genotype	Ref.
S. cerevisiae WY254	α ade2, can1, his3, leu2, trp1, ura3, hem2::LEU2, cys4::HIS3	See “Experimental Procedures”
S. cerevisiae WY79	α ade2, can1, his3, leu2, trp1, ura3, cys4::LEU2	This study
S. cerevisiae WY61	α his2, leu2, trp1, ura3, cys4::LEU2 + pHCBS	23 and 24
E. coli HU227	hemA41, relA1, spoT1, metB1, rrnB-2, mcrB1, creC510, Hem-p	45
E. coli RP523	thr-1, leuB6(Am), fhuA21, lacY1, hemB220, glnV44(AS), e14-, rfbC1, glpR200(glpc), thi-1	29