Microbial-induced carbonate precipitation is important in the global carbon cycle, especially in fixing atmospheric CO₂. Many simulation experiments have shown that microbes can induce carbonate precipitation, although there is no established understanding of the mechanism. In this study, several mineralization experiments were performed using Curvibacter lanceolatus strain HJ-1, including its secreted extracellular polymeric substances (EPS) and carbonic anhydrase (CA). We found that strain HJ-1, EPS, and CA could promote carbonate precipitation if compared with the respective control experiments (CK). Also, both HJ-1 and EPS1 experiments contained calcite and aragonite, whereas CA experiments formed calcite only. Therefore, HJ-1 and EPS is favorable for carbonate precipitation, especially for aragonite. Besides, the formation of calcite in the EPS2 experiments indicated that EPS contains a trace amount of CA, which might promote CO₂ hydration and eventually lead to carbonate precipitation. It was suggested that CA only provide CO₃²⁻ for the formation of carbonate minerals. In the absence of exogenous HCO₃-, the optimized calcification rate followed the order: HJ-1(49.5 %) > CA(6.6 %) > EPS2(4.1 %). In addition, MICP mechanisms was studied, an increase in pH and CO₂ hydration by CA play synergetic roles in providing supersaturated alkaline conditions in the system with bacteria. Finally, bacterial cells and EPS promote the formation of calcite and aragonite by acting as nucleation sites.

微生物诱导的碳酸盐沉淀在全球碳循环中很重要，特别是在固定大气 CO _{2 方面}。许多模拟实验表明，微生物可以诱导碳酸盐沉淀，尽管对该机制还没有明确的了解。在这项研究中，使用Curvibacter lanceolatus进行了几次矿化实验菌株HJ-1，包括其分泌的细胞外聚合物（EPS）和碳酸酐酶（CA）。我们发现，如果与各自的对照实验 (CK) 相比，菌株 HJ-1、EPS 和 CA 可以促进碳酸盐沉淀。此外，HJ-1 和 EPS1 实验均包含方解石和文石，而 CA 实验仅形成方解石。因此，HJ-1和EPS有利于碳酸盐沉淀，尤其是文石沉淀。此外，EPS2实验中方解石的形成表明EPS含有微量CA，可能促进CO ₂水化并最终导致碳酸盐沉淀。有人提出，CA 只为碳酸盐矿物的形成提供 CO ₃ ^2-。在没有外源性 HCO ₃的情况下-，优化后的钙化率顺序为：HJ-1(49.5 %) > CA(6.6 %) > EPS2(4.1 %)。此外，研究了 MICP 机制，CA增加的 pH 值和 CO ₂水合在为细菌系统提供过饱和碱性条件方面发挥协同作用。最后，细菌细胞和 EPS 通过充当成核位点促进方解石和文石的形成。