Update butters_gp30_gp31.md

Remove duplicates of title

content/3.defense-systems/butters_gp30_gp31.md

@@ -22,22 +22,14 @@ relevantAbstracts:
 
 ## Description
 The anti-phage defense system Butters_gp30_gp31 is encoded in the genomes of Actinobacteria, including in prophages.
-It was experimentally validated in the host _Mycobacterium smegmatis_, and displayed resistance against phages PurpleHaze and Alma.  
+It was experimentally validated in the host *Mycobacterium smegmatis* and displayed resistance against phages PurpleHaze and Alma.  
 
 ## Molecular mechanism
-To our knowledge the mechanism of action remains unknown.
-However the proteins of this system are predicted as a cytoplasmic protein (gp30) and a 4-pass transmembrane protein (gp31). The proposed mechanism of action is hypothesized to ressemble the RexA/B system of coliphage Lambda, where activation of gp30 by phage infection stimulates the ion channel gp31 which causes membrane depolarization and loss of intracellular ATP, which in turn, causes abortive infection.
+To our knowledge, the mechanism of action remains unknown.
+However, the proteins of this system are predicted as a cytoplasmic protein (gp30) and a 4-pass transmembrane protein (gp31). The proposed mechanism of action is hypothesized to resemble the RexA/B system of coliphage Lambda, where activation of gp30 by phage infection stimulates the ion channel gp31 which causes membrane depolarization and loss of intracellular ATP, which in turn, causes abortive infection.
  
 ## Example of genomic structure
 
-TODO
-
-## Distribution of the system among prokaryotes
-
-TODO
-
-## Example of genomic structure
-
 The Butters_gp30_gp31 is composed of 2 proteins: Butters_gp30 and Butters_gp31.
 
 Here is an example found in the RefSeq database: