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Background: Studies report high lead accumulations in surface soil horizons due to a large capacity for lead immobilization and accumulation as a result of the soil organic fraction, soil pH and redox. Lead (Pb) includes a group of large heavy metal in nature was toxic either on animal or human and did not provide an advantage function biologically. Organisms that live in environments polluted heavy metal do the mechanisms of adaptation to survive. Purpose: To identify bacteria resistant to lead from soil contaminated with lead, and to determine some physiological and biochemical activities. Methods: Soil samples were determined according to MNS3298-90 and heavy metal content was determined according to MNS5850: 2008 standard. Eight soil samples were collected from different parts of the city and we performed microbiological analysis. The total number of bacteria was cultured in Nutrient Agar medium and the lead-resistant bacteria were isolated from the 1 mM PbCl2 concentration in the medium to 9 mM. Results: Ubts4 strain of lead-resistant and lead-reducing bacteria was discovered in soil. Ubts4 was identified as B.thuringiensis after 16S rRNA gene sequence analysis. This strain was found to be active in reducing the concentration of lead alone in liquid media up to 46% in 1 month. Conclusion: B.thuringiensis strain is resistant to 9 mM (2503 mg/l) concentration of Lead (PbCl2) and is also resistant to Zinc, Chromium and Iron salts. But it is not resistant to Copper and Cadmium salts. Key words: Heavy metals, concentration, reduce, strain
