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Holin Gene

| posted 04 Jun, 2019 21:55
I am currently digging through literature to try to figure out why a holin gene is present in some phages but not others. The gene seems essential for host cell lysis with how it works with endolysins. The phage I am working with is a B1 phage, and so far no holin gene has been found in this subcluster. Does anyone have any insight on why some phages have holin genes and others don't?
| posted 05 Jun, 2019 18:04
In situations like this we are left with the very hand wavy answer that it is simply that the functions provided by the holins are being provided by proteins which cannot be detected with bioinformatic based tests. This can happen by either (1) convergent evolution (i.e. in this context, two completely different proteins evolving to carry out the function) or that (2) a completely different biochemical pathway has evolved in the B1 phages to "solve" the problem of how to lyse the host cell wall

In either situation bioinformatics fails us (by definition really) and we are left going back to the wet bench to answer the question "how do B1 phage lyse their host?"

So maybe someone else might be aware of published or unpublished results from bench work in this area and might have further insights.
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