CONICET | Buscador de Institutos y Recursos Humanos

Acidithiobacillus ferrooxidans is an iron oxidizing, facultative anaerobic, obligate chemolithotrophic bacterium that inhabits mesophilic and extremely acidic environments. Strains of this species are ubiquitous and have been isolated from diverse econiches, including ores, ore-concentrates and leaching solutions from the mining industry [1]. Frequently, it is the dominant iron oxidizer in acid mine drainage waters above pH 1.8 and different types of bioleaching operations [2]. Strains of this species play key roles in the recovery of copper, gold and other metals [3]. More than 500 isolates of A. ferrooxidans sensu stricto (as defined in [4]) have been recovered worldwide, yet fewer than 2%, have been sequenced so far. Clearly more genomic sequences of this species are required to understand the true biological diversity of the species from a genomic perspective. Relave Viejo is an abandoned mine tailing located in the Andacollo gold mining district (Neuquén, Argentina). This tailing stored the lime-treated left overs of gold concentrates processed in the site between 1976 and 1998. A microbiological survey performed between the years 2011 and 2015, using 16S rRNA gene-targeted deep sequencing, has revealed the presence of well established acidophilic microbial communities associated to the ore debris within the Relave Viejo tailing [5]. Members of the genus Acidithiobacillus, reckoned to be a highly diverse group of acidogenic bacteria, were among the dominant acidophilic taxa in these communities, in particular strains of the species A. ferrooxidans. Enrichment cultures held for ten months in total on airlift bioreactors [6], containing low pH culture media and mineral wastes from the Relave Viejo tailing, selected for a very low complexity community dominated by A. ferrooxidans-like iron oxidizers, designated RV1 culture. Here, we present the metagenome-derived draft genomic sequence of the RV1 culture in order to gain further insights into the genomic diversity of this model iron oxidizer and explore the genetic traits of this particular variant surviving lime-treatment in the semi-arid mountain range of northern Patagonia.