Fig. 5.
The four possible regulatory mechanisms of the lac system. The mechanisms are labeled by the mode of regulation of the glucose- and lactose-responsive regulators, where A/R means activator/repressor.
Official websites use .gov
A
.gov website belongs to an official
government organization in the United States.
Secure .gov websites use HTTPS
A lock (
) or https:// means you've safely
connected to the .gov website. Share sensitive
information only on official, secure websites.