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Heavy metal contamination is widespread in the environment and has resulted in numerous adverse consequences for the ecosystem. Ureolytic microorganisms are known to immobilize heavy metals by co-precipitation with calcium carbonates, which are formed during microbial hydrolysis of urea. In this work, we described a novel halophilic ureolytic bacterium (Exiguobacterium sp. JBHLT-3) and examined the relationship between ureolytic-driven mineralization of CaCO₃ and heavy metal mitigation. The growth of strain JBHLT-3 occurred at salinities between 3 and 12% with an optimum at 6%. This strain was capable of precipitating calcite and vaterite under non-growth conditions. Lead (Pb) was selected as a model heavy metal for this study and amended into the bio-precipitation systems at a starting concentration of 1 mM. The strain JBHLT-3 efficiently removed Pb from saline solutions via incorporation within …