Bioprospecting perchlorate-reducing bacteria: report of the genera Psychrobacter, Planococcus, Carnobacterium, and Paeniglutamicibacter isolated in Cierva Point, Antarctica, and its contribution to SDG 3

Perchlorate (ClO 4 − ) is a global contaminant that has been detected in various environmental matrices. ClO 4 − is considered an emerging pollutant because of its potent endocrine-disrupting effects, which impairs iodine uptake in the thyroid gland, and its high toxicity and persistence. Therefore, the development of technologies for its reduction in ecosystems is imperative; bioremediation is a promising technology for ClO 4 − reduction. In this study, bacterial strains isolated from marine sediments at Cierva Point, an Antarctic Specially Protected Area (ASPA No. 134), were characterized. The methodology consisted of four stages: i) isolation of the bacterial strains; ii) characterization of isolated strains by morphological, biochemical, and molecular traits; iii) susceptibility tests against NaCl and ClO 4 − ; iv) ClO 4 − removal assays using a selective electrode. The strains grew at 10 °C for 7 days and tolerated NaCl concentrations up to 30% w/v. All isolates grew at ClO 4 − concentrations of 10,000 mg/L, and five isolates also grew at 15,000 mg/L. Phylogenetic analysis identified members of the genera Psychrobacter, Planococcus, Carnobacterium , and Paeniglutamicibacter , capable of removing the contaminant in percentages between 40% and 52%. In alignment with UN Sustainable Development Goal 3 on promoting health and well-being, this project supports both ecosystem conservation and public health protection. In conclusion, the bacterial strains isolated from Cierva Point marine sediments, Antarctica, represent valuable resources for the bioremediation of ClO 4 − contamination, demonstrating significant potential to reduce and mitigate the pollutant in affected ecosystems.