PT  - JOURNAL ARTICLE
AU  - Catherine D. Stark
AU  - Teanna Bautista-Leung
AU  - Joanna Siegfried
AU  - Daniel Herschlag
TI  - Systematic investigation of the link between enzyme catalysis and cold adaptation
AID  - 10.1101/2021.08.25.457639
DP  - 2021 Jan 01
TA  - bioRxiv
PG  - 2021.08.25.457639
4099  - http://biorxiv.org/content/early/2021/08/25/2021.08.25.457639.short
4100  - http://biorxiv.org/content/early/2021/08/25/2021.08.25.457639.full
AB  - Cold temperature is prevalent across the biosphere and slows the rates of chemical reactions. Increased catalysis has been predicted to be a general adaptive trait of enzymes to reduced temperature, and this expectation has informed physical models for enzyme catalysis and influenced bioprospecting strategies. To broadly test rate as an adaptive trait to cold, we paired kinetic constants of 2223 enzyme reactions with their organism’s optimal growth temperature (TGrowth) and analyzed trends of rate as a function of TGrowth. These data do not support a prevalent increase in rate in cold adaptation. In the model enzyme ketosteroid isomerase (KSI), there was prior evidence for temperature adaptation from a change in an active site residue that results in a tradeoff between activity and stability. Here, we found that little of the overall rate variation for 20 KSI variants was accounted for by TGrowth. In contrast, and consistent with prior expectations, we observed a correlation between stability and TGrowth across 433 proteins. These results suggest that temperature exerts a weaker selection pressure on enzyme rate than stability and that evolutionary forces other than temperature are responsible for the majority of enzymatic rate variation.Competing Interest StatementThe authors have declared no competing interest.