Update pif.md

content/3.defense-systems/pif.md

@@ -23,7 +23,7 @@ relevantAbstracts:
 
 ## Description
 
-The Pif system (Phage Inhibition by F factors) was first described by Morisson & Malamy, 1971 :ref{doi=10.1038/newbio231037a0}. The Pif region of the F plasmid inhibits the phage T7 through abortive infection :ref{doi=10.1038/newbio231037a0,10.1007/BF00327934}.  
+The Pif system (Phage Inhibition by F factors) was first described by Morisson & Malamy :ref{doi=10.1038/newbio231037a0}. The Pif region of the F plasmid inhibits the phage T7 through abortive infection :ref{doi=10.1038/newbio231037a0,10.1007/BF00327934}.  
 
 ## Molecular mechanisms
 
@@ -31,7 +31,7 @@ PifA was later identified as the effector of the abortive infection :ref{doi=10.
 
 ## Example of genomic structure
 
-The Pif system is composed of 2 proteins: PifC and, PifA.
+The Pif system is composed of 2 proteins: PifC and PifA.
 
 Here is an example found in the RefSeq database: