8E9U

Crystal structure of E. coli aspartate aminotransferase mutant HEX in the ligand-free form at 303 K

Summary for 8E9U

• Entry DOI: 10.2210/pdb8e9u/pdb
• Descriptor: Aspartate aminotransferase, PYRIDOXAL-5'-PHOSPHATE, SULFATE ION, ... (4 entities in total)
• Functional Keywords: enzyme, designed protein, mutant protein, transferase
• Biological source: Escherichia coli
• Total number of polymer chains: 2
• Total formula weight: 90275.47

Authors

Chica, R.A.,St-Jacques, A.D.,Rodriguez, J.M.,Thompson, M.C. (deposition date: 2022-08-26, release date: 2022-11-09, Last modification date: 2023-10-18)

Primary citation

St-Jacques, A.D.,Rodriguez, J.M.,Eason, M.G.,Foster, S.M.,Khan, S.T.,Damry, A.M.,Goto, N.K.,Thompson, M.C.,Chica, R.A.
Computational remodeling of an enzyme conformational landscape for altered substrate selectivity.
Nat Commun, 14:6058-6058, 2023

PubMed Abstract: Structural plasticity of enzymes dictates their function. Yet, our ability to rationally remodel enzyme conformational landscapes to tailor catalytic properties remains limited. Here, we report a computational procedure for tuning conformational landscapes that is based on multistate design of hinge-mediated domain motions. Using this method, we redesign the conformational landscape of a natural aminotransferase to preferentially stabilize a less populated but reactive conformation and thereby increase catalytic efficiency with a non-native substrate, resulting in altered substrate selectivity. Steady-state kinetics of designed variants reveals activity increases with the non-native substrate of approximately 100-fold and selectivity switches of up to 1900-fold. Structural analyses by room-temperature X-ray crystallography and multitemperature nuclear magnetic resonance spectroscopy confirm that conformational equilibria favor the target conformation. Our computational approach opens the door to targeted alterations of conformational states and equilibria, which should facilitate the design of biocatalysts with customized activity and selectivity.

PubMed: 37770431
DOI: 10.1038/s41467-023-41762-0

Experimental method

X-RAY DIFFRACTION (1.94 Å)