A continuous treatment process was developed to investigate the capability of genetically engineered E coli to simultaneously accumulate mercuric ions and reproduce itself in a continuous stirred tank reactor (CSTR) system. The influence of dilution rate and initial Hg2+ concentration on continuous process was evaluated. Results indicated that the recombinant E. coli could effectively accumulate Hg2+ from aqueous solution with Hg2+ removal ratio up to about 90%, and propagate its cells at the same time in the continuous treatment system under suitable operational conditions. A kinetic model based on mass balance of Hg2+ was proposed to simulate the continuous process. The modeling results were in good agreement with the experimental data. (c) 2007 Elsevier B.V. All rights reserved.