An Encyclopedia of well-annotated DNA-binding TRanscription factors in Bacteria and Archaea.
| ENTRAF ID | ENTRAF0571 |
| Gene name | mqsR |
| Uniprot ID | MQSR_ECOLI |
| Organism | Escherichia coli (strain K12) |
| Aminoacid sequence | MEKRTPHTRLSQVKKLVNAGQVRTTRSALLNADELGLDFDGMCNVIIGLSESDFYKSMTTYSDHTIWQDVYRPRLVTGQVYLKITVIHDVLIVSFKEK |
| FASTA file | Download |
| Length | 98 |
| Function Uniprot | Toxic component of a type II toxin-antitoxin (TA) module. Plays a significant role in the control of biofilm formation and induction of persister cells in the presence of antibiotics. An mRNA interferase which has been reported to be translation-independent. It has also been reported to be translation-dependent. Cleavage has been reported to occur on either side of G in the sequence GCU. Also reported to cleave after C in GC(A/U) sequences. There are only 14 genes in E.coli W3110 (and probably also MG1655) that do not have a GCU sequence and thus are resistant to the mRNA interferase activity; among these is the gene for toxin GhoT. Overexpression of MqsR causes cessation of cell growth and inhibits cell proliferation via inhibition of translation as well as increasing persister cell formation; these effects are overcome by concomitant or subsequent expression of antitoxin MqsA. Cross-talk can occur between different TA modules. Ectopic expression of this toxin induces transcription of the relBEF TA module operon with specific cleavage of the relBEF mRNA produced. Regulates the expression of GhoT/GhoS, a type V TA module. Persistence depends on toxin GhoT activity, which MqsR controls at the post-transcriptional level by selectively degrading the antitoxin ghoS segment of the ghoST mRNA. Persister cells exhibit antibiotic tolerance without genetic change. mRNA interferases play a role in bacterial persistence to antibiotics; overexpression of this protein induces persisters resistant to coiprofloxacin and ampicillin. Overexpression leads to a dramatic increase in tolerance to the antibiotic ofloxacin. This TA system mediates cell growth during bile acid deoxycholate stress by degrading mRNA for probable deoxycholate-binding protein YgiS; bile acid detergents such as deoxycholate are important for host defense against bacterial growth in the gall bladder and duodenum. |
| Role | Unknown |
| Protein family | MqsR_toxin |
| Structure (PDB ID) | 3HI2 |