Large-scale filament formation inhibits the activity of CTP synthetase.
Bottom Line: Structure-guided mutagenesis and mathematical modeling further indicate that coupling activity to polymerization promotes cooperative catalytic regulation.This previously uncharacterized regulatory mechanism is important for cellular function since a mutant that disrupts CtpS polymerization disrupts E. coli growth and metabolic regulation without reducing CTP levels.We propose that regulation by large-scale polymerization enables ultrasensitive control of enzymatic activity while storing an enzyme subpopulation in a conformationally restricted form that is readily activatable.
Affiliation: Department of Molecular Biology, Princeton University, Princeton, United States.Show MeSH
Mentions: We have performed the requested control and reach the same conclusions. The new data and text (clarifying that the “substrates” added were UTP and ATP) are presented in Figure 1–figure supplement 5 and discussed in the Results section.
Affiliation: Department of Molecular Biology, Princeton University, Princeton, United States.