Evaluation of Cupriavidus's important role on the soil microbiota under cadmium stress through comparison of culture-dependent with culture-independent method. The soil near the drainage channel of a steel mills

Cadmium (Cd) pollution is one of the most harmful heavy-metals, its accumulation in crops can lead severe ecological and healthy problems. However, the responses of soil microbiome composition to Cd contamination, and the roles of key microbial species in these responses still remain more examined. In the present study, we treated soil with high concentrations Cd and evaluate microbial communities using both culture-dependent and culture-independent methods. We isolated 38 Cd-resistant bacteria from the soil sample under Cd stress, among which Cupriavidus is the most abundant genus and shows a high Cd-resistance. High-throughput sequencing of 16S rRNA gene indicated Cupriavidus significantly increased its relative abundances under Cd stress, and it may play an important role in microbial interaction network. Additionally, Cupriavidus sp. WS2 had strong absorption and accumulation capacity to Cd and biosynthesized CdNPs, and its inoculation with rice seedling can decrease the accumulation Cd in plant. Our data suggested that Cupriavidus might be a key taxon at microbial community level in the responses of Cd contamination, and harbored a potential for bioremediation of Cd.