I'm trying to isolate phages of dairy bacteria
(Lactococcus, Lactobacillus, Leuconostoc).
After assaying raw phage stock (probably a mixture
of phages) in double-layer agar method I got plaques,
but I fail in further replication of phage species
from a single plaque. I use MRS medium (Mg2+ & Ca2+ both 10mM).
Does phage adsorption to bacteria requires other cofactors?