1st International and 10th National Iranian Conference on Bioinformatics
Home Accepted Papers
Engineering carbonic anhydrase with improved solubility for green CO2 capture
Paper ID : 1170-ICB10
Authors:
Amirreza Farajnezhadi *, Mona Masoumparast, Mehran Habibi-Rezaei
Protein Biotechnology Research Lab (PBRL), School of Biology, University of Tehran, Tehran, Iran.
Abstract:
Carbonic anhydrase (CA) catalyzes the reversible conversion of CO2 to bicarbonate in living creatures. It is recommended for green CO2 capture technologies to enhance the low capturing rates of bioseparation processes [1] [2]. Different strategies were considered for the bioengineering of CA to stabilize the enzyme in extreme temperature and pH conditions, making it suitable for industrial operations [1] [3]. This study aims to improve enzyme solubility by recognizing aggregation-prone regions of CA and eliminating them. The 3D structure of the α-carbonic anhydrase (α-CA) from Thermovibrio ammonificans (TaCA; PDB ID: 4C3T), a thermostable tetrameric enzyme, was analyzed by Aggrescan3D 2.0 to identify aggregation hotspots on its surface [2] [4]. The average aggregation score of TaCA was calculated to be −0.9431, which indicates its low tendency for aggregation. However, seven aggregation-prone regions were discovered, centered on isoleucine 49, tyrosine 74, valine 237, cysteine 67, valine 73, leucine 45, and leucine 197, respectively by their severance. Cysteine 67 is necessary for the tetramerization of the enzyme that makes it thermostable, and leucine 197 is located in TaCA active site; therefore, these two remained untouched, and five other residues were mutated to alanine due to its low aggregation tendency. These mutations decreased the average aggregation score of TaCA by 10%, and aggregation hotspots disappeared, while the overall energy of protein structure experienced a 20.4 kJ/mol increase. Therefore, the mutated protein structure needs further dynamic examinations to assess enzyme stability. In conclusion, this study revealed that a small number of mutations could improve the overall solubility of the CA enzyme to prevent aggregation through CO2 bioseparation processes.
Keywords:
Protein aggregation; Carbonic Anhydrase; CO2 capture; Enzyme engineering.
Status : Paper Accepted (Poster Presentation)