A Discussion of the Regulatory Properties of Aspartate Transcarbamylase from Escherichia coli

摘要: Publisher Summary This chapter discusses the regulatory properties of aspartate transcarbamylase (ATCase) from Esterichia coli. Early circumstantial evidence for regulation in pyrimidine biosynthetic pathway at level enzyme activity came 1952 isotope competition studies Bolton et al., which they found that nonradioactive uracil or uridine added small amounts to nutrient medium growing Escherichia coli immediately and extensively suppresses endogenous bacterial synthesis pyrimidines 14C-labeled CO2. When becomes exhausted, mutant begins producing carbamyl large quantities, up one-half its dry weight 4 hours, reflecting derepression uncontrolled ATCase. is again provided mutant, formation ceases within minutes, indicating inhibition ATCase activity.