Table 3.

Bioassay to test hemin and hemoglobin utilization in V. vulnificus

Strains	Iron sources
	FAC	Hemin	Hemoglobin
ΔvenB, ΔtonB1, ΔtonB2, ΔtonB3	++	−	−
ΔvenB	++	++	++
ΔvenB, ΔhvtA	++	++	++
ΔvenB, ΔhupA	++	+	−
ΔvenB, ΔhvtA, ΔhupA	++	−	−
ΔvenB, ΔhvtA, ΔhupA, pMMB208-hvtA	++	+	+

⁺⁺Strong growth after 18 h

⁺weak growth after 18 h

⁻no growth after 18 h. Indicated strains were mixed with CM9 media containing agar supplemented with 20 µM EDDA (and 1 mM IPTG for the strain containing the pMMB208 plasmid) and poured into petri dishes. After solidification, different iron sources (FAC, 1 mg/ml; hemin, 10 µM; and hemoglobin, 50 µM) were spotted on the plates and growth halos around the spots of the reporter strains were monitored after 18 h. FAC was used as a positive control