Aluminum and Sulphate Removal by a Highly Al-Resistant Dissimilatory Sulphate-Reducing Bacteria Community

摘要

A highly Al-resistant dissimilatory sulphatereducing bacteria community was isolated from sludge of the wetland of Urgeiriça mine (community W). Thiscommunity showed excellent sulphate removal at the presence of Al3+. After 27 days of incubation, 73,86 and 81% of sulphate was removed in the presence of 0.48,0.90 and 1.30 mM of Al3+, respectively. Moreover,Al3+ was simultaneously removed: 55,85 and 78% of metal was removed in the presence of 0.48, 0.90 and 1.30 mM of Al3+, respectively. The dissociation of aluminiumlactate soluble complexes due to lactate consumption by dissimilatory sulphate-reducing bacteria can be responsiblefor aluminum removal, which probably precipitates as insoluble aluminium hydroxide. Phylogenetic analysis of 16S rRNA gene showed that this community wasmainly composed by bacteria closely related to Desulfovibrio desulfuricans. However, bacteria affiliated to Proteus and Ralstonia were also present in the community.