Update 3.defense-systems_trigger.md

content/2.general-concepts/3.defense-systems_trigger.md

@@ -17,14 +17,3 @@ One major caveat in the above approach is that in some cases mutant phages that
 
 ## General concepts: 
 Although much is still unknown regarding how bacterial immune systems sense phage infection, by combining the data observed so far, several general concepts in immune sensing are beginning to come to light. First, mechanistically diverse immune systems appear to have converged to sense common conserved phage components4.  These include the phage core replication machinery, host takeover machinery and structural components. Second, several studies have found cases in which defense occurs in a multi-layered fashion, whereby a second system is activated when the first one fails  :ref{doi=10.1016/j.cell.2020.09.065,10.1016/j.chom.2022.02.018,10.1006/jmbi.1995.0343}. Research in upcoming years is expected to reveal additional guiding principles in the ways bacteria detect phages. 
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-## References:
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-5.	Huiting E & Bondy-Denomy J. (2023) Defining the expanding mechanisms of phage-mediated activation of bacterial immunity. Curr. Opin. Microbiol. 74: 102325.doi: 10.1016/j.mib.2023.102325
-6.	Zhang T, Tamman H, Coppieters ’t Wallant K, Kurata T, LeRoux M, Srikant S, Brodiazhenko T, Cepauskas A, Talavera A, Martens C, Atkinson G C, Hauryliuk V, Garcia-Pino A, & Laub M T. (2022) Direct activation of a bacterial innate immune system by a viral capsid protein. Nature 612: 132–140. doi: 10.1038/s41586-022-05444-z
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