6NW4

Evolution of a computationally designed Kemp eliminase

Summary for 6NW4

• Entry DOI: 10.2210/pdb6nw4/pdb
• Descriptor: Indole-3-glycerol phosphate synthase, SULFATE ION, 6-NITROBENZOTRIAZOLE, ... (4 entities in total)
• Functional Keywords: kemp elimination, evolution, biosynthetic protein
• Biological source: Saccharolobus solfataricus (strain ATCC 35092 / DSM 1617 / JCM 11322 / P2) (Sulfolobus solfataricus)
• Total number of polymer chains: 1
• Total formula weight: 29072.30

Authors

Bunzel, A.,Mittl, P.,Hilvert, D. (deposition date: 2019-02-06, release date: 2019-07-24, Last modification date: 2024-01-24)

Primary citation

Bunzel, H.A.,Kries, H.,Marchetti, L.,Zeymer, C.,Mittl, P.R.E.,Mulholland, A.J.,Hilvert, D.
Emergence of a Negative Activation Heat Capacity during Evolution of a Designed Enzyme.
J.Am.Chem.Soc., 141:11745-11748, 2019

PubMed Abstract: Temperature influences the reaction kinetics and evolvability of all enzymes. To understand how evolution shapes the thermodynamic drivers of catalysis, we optimized the modest activity of a computationally designed enzyme for an elementary proton-transfer reaction by nearly 4 orders of magnitude over 9 rounds of mutagenesis and screening. As theorized for primordial enzymes, the catalytic effects of the original design were almost entirely enthalpic in origin, as were the rate enhancements achieved by laboratory evolution. However, the large reductions in Δ were partially offset by a decrease in Δ and unexpectedly accompanied by a negative activation heat capacity, signaling strong adaptation to the operating temperature. These findings echo reports of temperature-dependent activation parameters for highly evolved natural enzymes and are relevant to explanations of enzymatic catalysis and adaptation to changing thermal environments.

PubMed: 31282667
DOI: 10.1021/jacs.9b02731

Experimental method

X-RAY DIFFRACTION (3 Å)