Background: CO2 in the environment has been a burning issue and aggravated the threats of global warming. Various strategies are being used to decrease the level of releasing CO 2 . Biosequestration is a one of the available nontoxic, robust and eco-friendly approaches but still less evaluated. This study reports the role of microbial Carbonic Anhydrase (CA) in the formation of calcite by utilizing CO2. Methods: The marine Nocardiopsis lucentensis was studied for intracellular microbial CA. Isolate grown optimally at 2.5% CO2 saturated environment and procedure the calcium carbonate encrust in the presence of CaCl2. Results: The enzyme was found to catalyze the reaction in a wide range of pH and temperature with an optimum at 7.0 pH and 25°C. The 50 mM NaCl, KCl and MgCl2 were found to support the enzyme activity and 50 mM ZnCl 2 increases activity 1.5 fold. CA was able to withstand against sulphanilamide inhibitor and stable over prolonged incubation at 4 and 37°C. Conclusion: Calcite formation was evaluated with and without enzyme using marine water as a source of calcium ions. The result of SEM and EDX indicated the formation of larger flower-shaped particles compare to the small cubic particles formed without enzyme. The results suggest that the robustness of enzyme and suitability in the CO2 capture reactor.