TABLE 3.

Inhibitory effect of 5 μM DSF or BDSF addition on oxidation of soluble and insoluble energy sources in cultures of A. caldus, L. ferriphilum, and S. thermosulfidooxidans

Energy source (reference figure)	Inhibition by speciesa
	A. caldus	L. ferriphilum	S. thermosulfidooxidans
Soluble [tetrathionate/iron(II) ions] (Fig. S3)	−	+	+
Insoluble (chalcopyrite) (Fig. S4)	+	+	+

^a+, no biological oxidation of soluble substrates occurred within 32 days of incubation; chalcopyrite dissolution in assays with DSF or BDSF were significantly lower than in the control assays without DSF or BDSF addition; −, no inhibition, and substrate oxidation similar to assays without DSF or BDSF addition. Tetrathionate was used for A. caldus, iron(II) ions were used for L. ferriphilum, and tetrathionate or iron(II) ions were used for S. thermosulfidooxidans. Fig. S3 and S4 substantiate the summary represented by the indicators (±) shown here by providing quantitative measurements of iron(II) ions, pH values, and planktonic cell counts [Fig. S3, soluble energy sources of iron(II)ions or tetrathionate] and total copper ions (Fig. S4, insoluble energy source of chalcopyrite).