Molecular Characterization of Copper and Cadmium Resistance Determinants in the Biomining Thermoacidophilic Archaeon Sulfolobus metallicus
Cotranscription analysis of copMA1 and copMA2 genes. cDNA was synthesized with a reverse primer (dotted arrows) hybridizing toward the 3′ end of either copA1 (a) or copA2 (b). S. metallicus total RNA was extracted at the late exponential phase from a culture growing in presence of 20 mM Cu. PCR amplifications were carried out with these cDNAs and each corresponding primer pair (black arrows) as listed in Table 1. (c) and (d) show RT-PCR products obtained for the copMA1 and copMA2 intergenic regions, respectively. Reverse transcriptase reactions with (+) and without the Improm II reverse transcriptase enzyme were carried out in order to exclude amplification due to genomic DNA contamination. Expected sizes (in base pairs) for the corresponding PCR products are given in (a) and (b).