Merge branch 'main' into dev

content/3.defense-systems/mqsrac.md

@@ -6,9 +6,17 @@ tableColumns:
       doi: 10.1101/2023.02.25.529695
       abstract: |
         Myriad bacterial anti-phage systems have been described and often the mechanism of programmed cell death is invoked for phage inhibition. However, there is little evidence of ‘suicide’ under physiological conditions for these systems. Instead of death to stop phage propagation, we show here that persister cells, i.e., transiently-tolerant, dormant, antibiotic-insensitive cells, are formed and survive using the Escherichia coli C496_10 tripartite toxin/antitoxin system MqsR/MqsA/MqsC to inhibit T2 phage. Specifically, MqsR/MqsA/MqsC inhibited T2 phage by one million-fold and reduced T2 titers by 500-fold. During T2 phage attack, in the presence of MqsR/MqsA/MqsC, evidence of persistence include the single-cell physiological change of reduced metabolism (via flow cytometry), increased spherical morphology (via transmission electron microscopy), and heterogeneous resuscitation. Critically, we found restriction-modification systems (primarily EcoK McrBC) work in concert with the toxin/antitoxin system to inactivate phage, likely while the cells are in the persister state. Phage attack also induces persistence in Klebsiella and Pseudomonas spp. Hence, phage attack invokes a stress response similar to antibiotics, starvation, and oxidation, which leads to persistence, and this dormant state likely allows restriction/modification systems to clear phage DNA.
+         
+contributors:
+relevantAbstracts:
+    - doi: 10.1038/s41564-022-01219-4
+    - doi: 10.1101/2023.02.25.529695 
+
 ---
 
 # MqsRAC
+## Description
+## Molecular mechanisms
 ## Example of genomic structure
 
 The MqsRAC system is composed of 2 proteins: mqsR and, mqsC.
@@ -29,6 +37,8 @@ Among the 22k complete genomes of RefSeq, this system is present in 26 genomes (
 
 *Proportion of genome encoding the MqsRAC system for the 14 phyla with more than 50 genomes in the RefSeq database.* 
 
+## Structure
+
 ## Experimental validation
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-## Relevant abstracts
+