[falsestprophet]

In my lab we developed a different assay that favoured the isolation of generalist phages and we were really successful in finding broad host range phages (many were multi-genera in host range).

Did your group publish anything on this approach? If so, could you share a link to one or some of the papers?

[danieltillett]

Yes we did, but we didn’t make a huge deal about it in the papers (it is just in the methods sections). If you want to find my phage papers just have a look at my profile on ResearchGate [1].

The basic idea is pretty straightforward. Rather than plating a filtered sample directly onto a overlay plate of a single bacterial strain, we pre-enriched for phages in a mixed culture of multiple bacterial strains (we would sometime use up to 50 different strains/species in the one enrichment flask). What this does is give the broad host range phages a competitive advantage since they can reproduce in multiple hosts and outgrow the narrow host range phages. When you plate out onto a specific strain for isolation of the phages you end up with mostly broad host range phages.

The idea is so obvious I am surprised it is not more widely used in the field. It seems to be the norm to just use a single bacterial strain for the phage isolation. I think most people just assume all phages are narrow host range.

1. https://www.researchgate.net/profile/Daniel_Tillett2