Table 1.

Species composition at late exponential phase of pure and mixed cultures used in this study

Culture	Q-PCR determinations
	Total bacteria/mL	A. ferrooxidans/mL	A. thiooxidans/mL
A. thiooxidans	2.30 × 108	n.d.	6.67 × 108
A. ferrooxidans	2.70 × 108	2.56 × 108	n.d.
A. thiooxidans + A. ferrooxidans	4.31 × 108	1.83 × 105	5.46 × 108

n.d. not detected