Carbonic Anhydrase Robustness for Use in Nanoscale CO₂ Capture Technologies.

Area of Science:

• Biochemistry and Environmental Science
• Enzyme Engineering for Carbon Capture

Background:

• Growing reliance on fossil fuels has led to record-high atmospheric carbon dioxide (CO2) emissions.
• Conventional CO2 absorption methods face limitations in industrial flue gas applications.
• Carbonic anhydrase (CA) offers a promising alternative for enhanced CO2 capture due to its efficiency.

Purpose of the Study:

• To investigate the structural basis of carbonic anhydrase (CA) enzyme stability for industrial applications.
• To evaluate the performance of mesophilic and thermophilic CA variants under various stress conditions.

Main Methods:

• Enzyme activity assays were conducted on CA variants at different temperatures.
• Molecular dynamics simulations were employed to assess conformational stability.
• The impact of atmospheric pollutants (nitrogen oxides and sulfur oxides) on enzyme activity was examined.

Main Results:

• Thermostable CA variants exhibited increased conformational stability and maintained high activity levels after prolonged incubation at elevated temperatures.
• CA activity remained robust in thermostable variants despite pH fluctuations caused by nitrogen and sulfur oxides.
• Significant loss of CA activity was observed only at very high concentrations of nitrogen and sulfur oxides.

Conclusions:

• Thermostable CA variants demonstrate superior stability and activity, making them suitable for industrial CO2 capture.
• Enzyme performance can be maintained under challenging industrial conditions, with potential mitigation strategies for pollutant effects.
• Further research into buffered solutions may further enhance CA stability in the presence of industrial flue gas pollutants.