[1][2][3] It encodes a two-component transcriptional quorum-sensing (QS) system activated by an autoinducing, thiolactone-containing cyclic peptide (AIP).
[6][7] The agr receptor, AgrC, is a model histidine phosphokinase (HPK) that has been used to decipher the molecular mechanism of signal transduction.
Later in growth, these genes are down-regulated by RNAIII and those encoding toxins, hemolysins and other virulence-related proteins, are turned on, enabling the organism to establish and promulgate its pathological programs, such as abscess formation.
In keeping with this behavior, mutations inactivating agr function enhance the stability of biofilms,[14] which are key to the maintenance of chronic infections.
Agr is widely conserved among Bacillota[15] and has a well-defined role in virulence regulation in several genera, especially Listeria and Clostridia.