The genes encoding the enzymes for arginine biosynthesis are located at several positions around the genome of E. coli. The ArgR transcription regulator coordinates their expression. The activity of ArgR is modulated by arginine. Upon binding arginine, ArgR dramatically changes its affinity for the regulatory sequences in the promoters of the genes for the arginine biosynthetic enzymes. a. Given that ArgR is a transcriptional repressor, would you expect ArgR would bind more tightly, or less tightly, to the regulatory sequences when arginine is abundant.
b. If ArgR functioned instead as a transcription activator, would you expect the binding of arginine to increase, or decrease, its affinity for its regulatory sequences