Comparative genomics begins to unravel the ecophysiology of bioleaching

A comparison of the metabolic potential of 20 bioleaching microorganisms and their close relatives from the Eubacteria and Archaea kingdoms permits the prediction of inter- and intra-species physiological interactions (ecophysiology) during spatial and temporal changes that are known to occur within industrial bioleaching heaps. Genome analysis has allowed preliminary models to be built for genes and pathways involved in key processes such as nitrogen and carbon cycling, sulfur and iron uptake and homeostasis, extra-cellular polysaccharide biosynthesis, heavy metal resistance and energy metabolism. This paper will focus on the diverse ways that bioleaching microorganisms obtain carbon from their environment with a particular emphasis on elucidating how these processes might be expected to vary over space and time during the lifetime of a bioleaching operation. It is anticipated that this knowledge will improve our understanding of fundamental biological processes in extremely acidic environments. ► At least 20 genome sequences of bioleaching microbes are publicly available. ► Genomics has identified different CO2 fixation strategies used during bioleaching. ► Genomics suggests models of the ecophysiology of bioleaching microbial consortia. ► There is more microbial diversity in bioleaching heaps than previously estimated.