| Brackets denote operon boundaries and arrows indicate the direction of transcription of each gene. |
| A lower intensity of mutagenesis can explain all observed revertants if each mutagenized cell has multiple copies of the lac operon. |
| It has been noted that coexpressed genes are frequently situated as contiguous clusters within an operon. |
| The transcription of the operon is coordinately repressed in the presence of excess pyrimidine nucleotides. |
| Starvation for histidine derepresses the entire operon, the longest then known. |
| In addition to the lac operon, a number of other synthetic and natural genetic circuits have been analyzed for robustness and evolvability. |
