Mesorhizobium loti carbonic anhydrase (MlCA), an intrinsically high catalytic enzyme, has been employed for carbon dioxide capture and sequestration. However, recombinant expression of MlCA in Escherichia coli often forms inclusion bodies. Hence, protein partners such as fusion-tags and molecular chaperones are involved in regarding reduce the harshness of protein folding. TrxA-tag and GroELS have been chosen to co-express with MlCA in E. coli under an inducible T7 promoter or a constitutive J23100 promoter to compare productivity and activity. The results possessed that coupling protein partners effectively increased soluble MlCA up to 2.9-folds under T7 promoter, thus enhancing the CA activity by 120% and achieving a 5.2-folds turnover rate. Besides, it has also shifted the optimum temperature from 40 °C to 50 °C, promoted stability in the broad pH range (4.5 to 9.5) and the presence of various metal ions. Based on the in vitro assay and isothermal titration calorimetry (ITC) analysis, GroELS enhancing CA activity was due to change the intrinsic thermodynamic properties of the enzyme from endothermic to exothermic reaction (i.e., ∆H = 89.8 to −121.8 kJ/mol). Therefore, the collaboration of TrxA-MlCA with GroELS successfully augmented CO₂ biomineralization.

内生根瘤菌碳酸酐酶（M1 CA），本质上是高催化酶，已被用于二氧化碳的捕获和隔离。然而，M1CA在大肠杆菌中的重组表达通常形成包涵体。因此，蛋白质伴侣如融合标签和分子伴侣涉及减少蛋白质折叠的苛刻性。选择TrxA-tag和GroELS在诱导型T7启动子或组成型J23100启动子下与Ml CA在大肠杆菌中共表达，以比较生产力和活性。结果表明，偶联蛋白伴侣可有效增加可溶性M1在T7启动子下，CA高达2.9倍，从而使CA活性提高了120％，并实现了5.2倍的周转率。此外，它还将最佳温度从40°C移至50°C，提高了在宽pH范围（4.5至9.5）中的稳定性以及各种金属离子的存在。根据体外测定和等温滴定热分析（ITC），GroELS增强CA活性的原因是酶的内在热力学性质从吸热反应转变为放热反应（即∆H = 89.8至-121.8 kJ / mol）。因此，TrxA- M1 CA与GroELS的合作成功地增强了CO ₂生物矿化作用。