Title
Engineering de novo disulfide bond in bacterial α-type carbonic anhydrase for thermostable carbon sequestration
Author
Byung Hoon Jo, Tae Yoon Park, Hyun June Park, Young Joo Yeon, Young Je Yoo, Hyung Joon Cha
Year
2016
Journal
Scientific Reports
Abstract
Exploiting carbonic anhydrase (CA), an enzyme that rapidly catalyzes carbon dioxide hydration, is an attractive biomimetic route for carbon sequestration due to its environmental compatibility and potential economic viability. However, the industrial applications of CA are strongly hampered by the unstable nature of enzymes. In this work, we introduced in silico designed, de novo disulfide bond in a bacterial α-type CA to enhance thermostability. Three variants were selected and expressed in Escherichia coli with an additional disulfide bridge. One of the variants showed great enhancement in terms of both kinetic and thermodynamic stabilities. This improvement could be attributed to the loss of conformational entropy of the unfolded state, showing increased rigidity. The variant showed an upward-shifted optimal temperature and appeared to be thermoactivated, which compensated for the lowered activity at 25 °C. Collectively, the variant constructed by the rapid and effective de novo disulfide engineering can be used as an efficient biocatalyst for carbon sequestration under high temperature conditions.
Full Article
Instrument
J-???
Keywords
Circular dichroism, Secondary structure, Thermal stability, Protein folding, Thermodynamics, Biochemistry