I didn’t think the protocol was that amazing so it is just described in passing in our papers (see [1] for an example). The basic idea is really simple. Phages

I didn’t think the protocol was that amazing so it is just described in passing in our papers (see [1] for an example). The basic idea is really simple. Phages come as both generalists and specialists (and all grades in between). The specialists grow on a limited range of bacterial strains, while the generalists can grow on a wide range of bacteria (even different genera). The specialist phages grow faster than the generalists in a single bacterial strain as they are better adapted to their specific host. The problem is that when most groups isolate phages from the environment they only use one bacterial strain at a time so they end up isolating specialists rather than the generalists; the generalists are just too slow to form visible plaques in the presence of specialists. The solution to isolating broad host range phages is to use multiple bacterial strains in the enrichment and isolation process (we used up to 50 at a time). Under these conditions the generalists grow faster since they have more hosts they can infect (i.e. the specialist can only reproduce in one bacterial strain, while the generalists can reproduce in multiple). This tips the isolation process towards pulling out generalists phages that have a broad host range. I have to say when I entered the field I thought that this was the way everyone isolated phages as it is so obvious, but I was wrong. 1. http://aem.asm.org/content/77/4/1389 http://aem.asm.org/content/77/4/1389