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| Type |
Symposium |
| Area |
Structure and Function of Membrane Proteins |
| Room No. |
Room 314 |
| Time |
THU 17:00-: |
| Code |
LIFE1-3 |
| Subject |
Structural insights into highly thermostable carbonic anhydrase for CO2 capture and sequestration technology |
| Authors |
Mi Sun Jin
Division of Life Science, Gwangju Institute of Science and Technology, Korea |
| Abstract |
Bacterial α-type carbonic anhydrase (α-CA) is a zinc metalloenzyme that catalyzes the reversible and extremely rapid interconversion of carbon dioxide to bicarbonate. In this study we report the first crystal structure of hyperthermostable α-CA from Persephonella marina EX-H1 (pmCA). The structure reveals a compact folding of the pmCA homodimer in which each monomer consists of ten-stranded β-sheet in the center surrounded by several α-helices and additional β-strands in the periphery. Catalytic zinc ion is coordinated by highly conserved residues of three histidines and a bicarbonate. Extensive intermolecular network by hydrogen bonds, ionic and hydrophobic interactions might significantly confer a high pH and thermal stability to the pmCA. Furthermore, an intramolecular disulfide bond gives an additional stabilization of the pmCA structure. We also present the first demonstration of novel binding sites for five calcium ions at the crystallographic interface, serving as a molecular glue to link the negatively charged otherwise repulsive surfaces. The data obtained in this study offer essential information that can be exploited to engineer α-CAs in order to obtain enzymes with improved thermostability for high tolerance to the harsh conditions of the CO2 capture and sequestration technology. |
| E-mail |
misunjin@gist.ac.kr |
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122nd General Meeting of the KCS