FIG. 3.

(A) Locations of primers used to determine the divergent arrangement of the putative arsR and arsC genes and the arsBH genes in different strains of T. ferrooxidans and other biomining bacteria. Primers located within the arsB and arsC genes were used to amplify the 450-bp region between these two genes. (B) Ethidium bromide-stained agarose gel of the PCR amplification products, prepared by using chromosomal DNA from different biomining bacteria. Abbreviations: T.f., T. ferrooxidans; L.f., L. ferrooxidans; T.t., T. thiooxidans; T.c., T. caldus; E.c., E. coli. +ve, positive; -ve, negative.