Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Aims To isolate and characterize the cultivable community of hydrolase producers (amylase, protease, lipase, DNase, xylanase and pullulanase) inhabiting heavy-metal-contaminated soils in extreme conditions from the Atacama Desert. Methods and Results A total of 25 bacterial strains showing hydrolytic activities have been selected including halotolerants, extremely halotolerants and moderate halophiles. Most hydrolase producers were assigned to the family B acillaceae, belonging to the genera Bacillus (nine strains), Halobacillus (seven strains) and Thalassobacillus (five strains) and four isolates were related to members of the families Pseudomonadaceae, Halomonadaceae and Staphylococcaceae. The selected strains were then characterized for their tolerance pattern to six heavy metals, measured as minimal inhibitory concentrations (MICs). Conclusions The diversity found in the cultivable bacterial community analysed is more limited than that detected in other ecological studies owing to the restrictive conditions used in the screening. The dominant bacteria were Firmicutes and particularly, species related to the genus Bacillus. Significance and Impact of the Study This study is focused on the characterization of extremophilic hydrolytic bacteria, providing candidates as a source of novel enzymes with biotechnological applications.1133550559Spanish Ministry of Science and Education [CTM 2006-03310]Junta de Andalucia [P08-RMN-3515]University of SevillaCoordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Spanish Ministry of Science and Education [CTM 2006-03310]Junta de Andalucia [P08-RMN-3515]