pfam15723: MqsR_toxin (This model is not part of the current CDD release)
Motility quorum-sensing regulator, toxin of MqsA
MqsR_toxin is a family of bacterial toxins that act as an mRNA interferase. MqsR is the gene most highly upregulated in E. coli persister cells and it plays an essential role in biofilm regulation and cell signalling. It forms part of a bacterial toxin-antitoxin TA system, and as expected for a TA system, the expression of the MqsR toxin leads to growth arrest, while co-expression with its antitoxin, MqsA, rescues the growth arrest phenotype. In addition, MqsR associates with MqsA to form a tight, non-toxic complex and both MqsA alone and the MqsR:MqsA2:MqsR complex bind and regulate the mqsR promoter. The structure of MqsR shows that is is a member of the RelE/YoeB family of bacterial RNases that are structurally and functionally characterised bacterial toxins.y characterized bacterial toxins.
Jiyao W et al.(2023). "The conserved domain database in 2023.",