A psychrotolerant Ni-resistant Bacillus cereus D2 induces carbonate precipitation of nickel at low temperature

Psychrotolerant bacteria play a particularly important role in the remediation of heavy metal in contamination sites at low temperatures. In the current study, a psychrotolerant Ni-resistant bacterial strain, identified as Bacillus cereus D2, was isolated from a nickel mining area in China. The isolated strain could produce a large amount of urease enzyme (194.6 U/mL), grow well in harsh environmental conditions at a temperature of 10 degrees C, and at a Ni (II) concentration up to 400 mg/L. Also, under the low temperature (10 degrees C), this strain has been revealed to induce carbonate precipitation (Ni2CO3(OH) 2 center dot H2O) through biomineralization for removing the high efficiency of Ni ions (73.47%) from the culture solution. Furthermore, strain D2 could immobilize the DTPA-Ni in contaminated soil under the case of the laboratory condition at 10 degrees C. These data support that the psychrotolerant bacterial strain D2 may play an important role in remediation technology by eliminating Ni ions from the contaminated soil at low temperatures.