FNR

From WikiMD's Food, Medicine & Wellness Encyclopedia

FNR is a protein that is involved in the anaerobic regulation of bacteria. It is a global transcription factor that is found in Escherichia coli and other Enterobacteriaceae. FNR stands for "fumarate and nitrate reduction regulatory protein", which indicates its role in the regulation of gene expression in response to oxygen levels.

Structure[edit | edit source]

FNR is a monomer that can exist in two states: an active, dimeric form and an inactive, monomeric form. The active form of FNR contains a 4Fe-4S cluster, which is sensitive to oxygen. When oxygen is present, the cluster is oxidized and the protein becomes inactive. In the absence of oxygen, the cluster is reduced and the protein becomes active.

Function[edit | edit source]

The primary function of FNR is to regulate the expression of genes involved in anaerobic metabolism. When oxygen levels are low, FNR activates the transcription of genes involved in the utilization of alternative electron acceptors, such as nitrate and fumarate. In addition, FNR represses the transcription of genes involved in aerobic metabolism.

Role in Disease[edit | edit source]

While FNR is essential for the survival of bacteria in anaerobic conditions, it can also contribute to the pathogenicity of certain bacteria. For example, in Salmonella enterica, FNR regulates the expression of genes involved in the invasion of host cells.

See Also[edit | edit source]

References[edit | edit source]

FNR Resources
Doctor showing form.jpg
Wiki.png

Navigation: Wellness - Encyclopedia - Health topics - Disease Index‏‎ - Drugs - World Directory - Gray's Anatomy - Keto diet - Recipes

Search WikiMD


Ad.Tired of being Overweight? Try W8MD's physician weight loss program.
Semaglutide (Ozempic / Wegovy and Tirzepatide (Mounjaro) available.
Advertise on WikiMD

WikiMD is not a substitute for professional medical advice. See full disclaimer.

Credits:Most images are courtesy of Wikimedia commons, and templates Wikipedia, licensed under CC BY SA or similar.

Contributors: Prab R. Tumpati, MD