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.
Differential control of Irr-repressed genes by the variable affinity of Irr for target promoters. Low-affinity promoters such as those found in the housekeeping gene leuC or pbgS allow some expression (derepression) even under low-iron conditions, where Irr levels are highest. High-affinity promoters such as those found for mbfA and bfr repress expression strongly at low and intermediate levels of iron and are derepressed only at high iron levels.
