Utility of Immobilized Recombinant Carbonic Anhydrase of Bacillus halodurans TSLV1 on the Surface of Modified Iron Magnetic Nanoparticles in Carbon Sequestration

Abstract

Carbonic anhydrase (CA) based conversion of CO2 to CaCO3 has been identified as a green and economic strategy to sequester CO2 from flue gas and industrial emissions. The method is, however, cost-intensive as an efficient immobilization method for reusing the enzyme poses a major challenge. In this investigation, the recombinant carbonic anhydrase of polyextremophilic bacterium Bacillus halodurans TSLV1 (rBhCA) has been immobilized on the surface of modified magnetic (silanized) iron oxide nanoparticles (Si-MNPs). The immobilized rBhCA exhibited improvement in alkalistability and retained significantly high activity at elevated temperatures as compared to the free rBhCA. Furthermore, rBhCA immobilized on Si-MNPs could be easily isolated from the reaction by magnetic separation. After 22 repeated uses, the immobilized rBhCA retained 50% of the initial activity and could be stored for 28 days without any loss in activity. rBhCA-Si-MNPs accelerated the onset of CaCO3 precipitation over that of the free enzyme, but the amount of CaCO3 precipitated was not affected, suggesting that the silanized MNPs act as efficient supports for immobilization of CA for utility in CO2 sequestration.

Covalent Immobilization of β-Glucosidase into Mesoporous Silica Nanoparticles from Anhydrous Acetone Enhances Its Catalytic Performance

“…β-Glucosidase covalently immobilized on nanoparticle carriers has been studied by several authors [20,[27][28][29]. However, the use of mesoporous nanoparticles can lead to a number of advantages due to their high surface area and pore size [30]. The porous structure protects the enzyme against the harsh conditions of the reaction environment, such as high temperatures, extreme pH, and the presence of bubbles or inhibitors, creating an ideal micro-environment for the expression of the enzymatic activity [31,32].…”

Enzymatic treatment of phenolic pollutants by a small laccase immobilized on APTES-functionalised magnetic nanoparticles

“…Finally, MNPs were dried under vacuum overnight at 60 °C. Surface modification of the dried MNPs was carried out using (3-aminopropyl)-triethoxysilane (APTES) as described by Faridi et al (2017). One gram of MNPs were dispersed in a mixture of 20% (w/v) APTES and 4 mL glycerol, and the resulting mixture was heated at 90 °C for 2 h under nitrogen sparging and stirring.…”

“…Adsorption is a relatively simple method, however, leaching of the enzyme from the immobilized matrix after a few cycles limits its application (Sheldon and Woodley 2018). In contrast, covalent binding provides an advantage over the adsorption method by stabilising strong bonding between the enzyme and the matrix via a chemical reaction, thereby minimising enzyme leaching (Faridi et al 2017). Among the several immobilization matrices that have been studied, magnetic nanoparticles (MNPs) have proven to be a promising candidate for the immobilization of enzymes (Ranjan et al 2018).…”

“…Silanization is a viable alternative owing to its responsivity, high stability, low cytotoxicity as well as the ease of surface chemical transformation. In addition, no specialized equipment is required, making silanization an ideal method for functionalization (Faridi et al 2017). Despite these favourable properties, silanization has not been used in the immobilization of laccase.…”

Microbial Carbonic Anhydrases in Biomimetic Carbon Sequestration for Mitigating Global Warming: Prospects and Perspectives

“…It is also very easy and cost effective technique, which can be carried out simply in aqueous or organic media at moderate temperatures (Xu et al, 2014 ). Faridi et al ( 2017 ) showed that even after 22 cycles of reuse, recombinant α–CA (rBhCA) from B. halodurans TSLV1 immobilized on silanized iron MNPs (rBhCA-Si-MNPs) lost only 50% of activity. Nickel nanoparticles have been successfully used as a direct catalyst for CO 2 hydration reaction for assessing their application in CO 2 mineralization (Bhaduri et al, 2015 ).…”