Open AccessSingle‐cell zeroth‐order protein degradation enhances the robustness of synthetic oscillator
Author(s) -
Wong Wilson W,
Tsai Tony Y,
Liao James C
Publication year - 2007
Publication title -
molecular systems biology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 8.523
H-Index - 148
ISSN - 1744-4292
DOI - 10.1038/msb4100172
Subject(s) - robustness (evolution) , kinetics , population , biology , zeroth law of thermodynamics , biological system , protein degradation , parametric statistics , biophysics , degradation (telecommunications) , synthetic biology , physics , microbiology and biotechnology , biochemistry , bioinformatics , gene , mathematics , thermodynamics , computer science , statistics , classical mechanics , telecommunications , demography , sociology
In Escherichia coli , protein degradation in synthetic circuits is commonly achieved by the ssrA ‐tagged degradation system. In this work, we show that the degradation kinetics for the green fluorescent protein fused with the native ssrA tag in each cell exhibits the zeroth‐order limit of the Michaelis–Menten kinetics, rather than the commonly assumed first‐order. When measured in a population, the wide distribution of protein levels in the cells distorts the true kinetics and results in a first‐order protein degradation kinetics as a population average. Using the synthetic gene‐metabolic oscillator constructed previously, we demonstrated theoretically that the zeroth‐order kinetics significantly enlarges the parameter space for oscillation and thus enhances the robustness of the design under parametric uncertainty.