Sandbox Reserved 1846: Difference between revisions

From Proteopedia
Jump to navigationJump to search
No edit summary
No edit summary
Line 45: Line 45:


=== Ser283 & Asp238 ===
=== Ser283 & Asp238 ===
Two wild-type residues, <scene name='10/1075247/S283-d238/5'>Ser283 and Asp238</scene>, were engineered to form a disulfide bond by replacing them with Cys. This decision was based on their spatial proximity in the 3D structure and their location in a region that resembles metal-binding sites in homologous PET-degrading enzymes. Unlike those metal-dependent sites, the LCC structure lacked coordinated ions. For that reason, the researchers engineered a covalent linkage instead to increase thermal stability without requiring additives like calcium. The wild-type protein has a melting point of 84.7°C, while the <scene name='10/1075248/C283-c238/2'>S283C and D238C mutant</scene> increased the melting point to 94.5°C, a 9.8°C improvement, which is higher than any other mutations. However, this increase in stability was accompanied by a 28% decrease in enzymatic activity compared to the wild-type. This trade-off between stability and activity shows the balance in enzyme engineering, as increasing structural integrity can sometimes restrict the flexibility needed for catalytic function.
Two wild-type residues, <scene name='10/1075247/S283-d238/5'>Ser283 and Asp238</scene>, were engineered to form a disulfide bond by replacing them with Cys. This decision was based on their spatial proximity in the 3D structure and their location in a region that resembles metal-binding sites in homologous PET-degrading enzymes. Unlike those metal-dependent sites, the LCC structure lacked coordinated ions. For that reason, the researchers engineered a covalent linkage instead to increase thermal stability without requiring additives like calcium. The wild-type protein has a melting point of 84.7°C, while the <scene name='10/1075248/4ebo_disulfide_bond_skyblue/1'>S283C and D238C mutant</scene> increased the melting point to 94.5°C, a 9.8°C improvement, which is higher than any other mutations. However, this increase in stability was accompanied by a 28% decrease in enzymatic activity compared to the wild-type. This trade-off between stability and activity shows the balance in enzyme engineering, as increasing structural integrity can sometimes restrict the flexibility needed for catalytic function.


== Group Mutations ==
== Group Mutations ==