Update prrc.md

#263 (closed)

content/3.defense-systems/prrc.md

@@ -10,9 +10,25 @@ tableColumns:
     Activator: Direct
     Effector: Nucleic acid degrading
     PFAM: PF00270, PF02384, PF04313, PF04851, PF12008, PF12161, PF13166, PF18766
+contributors:
+    - Ernest Mordret
+relevant abstracts:
+    - doi: 10.1186/1743-422X-7-360
+    - doi: 10.1006/jmbi.1995.0343
 ---
 
 # PrrC
+
+## Description
+
+The PrrC system protects bacteria against phages via an abortive infection. It is composed of a single effector protein, but relies on the presence of a full type Ic restriction-modification system in the vicinity. PrrC proteins are therefore typically found embedded in a larger RM system.
+
+## Molecular mechanism
+The effector protein prrC complements a RM system by cutting tRNALys in the anticodon loop, upstream of the wobble nucleotide and causes the arrest of phage protein synthesis and phage growth.
+prrC serves as a guardian of the acrivity of EcoprrI, which can be inactivated by the Stp peptide of phage T4 at the beginning of infection. Inactivation of EcoprrI by Stp induces a conformation change that in turn activates PrrC, releasing its nuclease activity and stalling host and phage growth :ref{doi=10.1006/jmbi.1995.0343}.
+Because it sabotages the host's translation machinery, prrC is considered to be an abortive infection system. 
+
+
 ## Example of genomic structure
 
 The PrrC system is composed of 4 proteins: EcoprrI, Type_I_S, PrrC and, Type_I_REases.
@@ -78,14 +94,3 @@ end
     style Title3 fill:none,stroke:none,stroke-width:none
     style Title4 fill:none,stroke:none,stroke-width:none
 </mermaid>
-## Relevant abstracts
-
-::relevant-abstracts
----
-items:
-    - doi: 10.1006/jmbi.1995.0343
-    - doi: 10.1186/1743-422X-7-360
-
----
-::
-