Interactions between E. coli phage and cell debris

At the end of their infection cycle, many bacteriophages lyse host cells using a coordinated set of proteins such as holin, endolysin, and spanin, fragmenting the bacterium and releasing phage virions. The resulting bacterial debris fragments can retain phage receptors, creating potential decoys that could inactivate phage via nonproductive binding. Here, we investigate how a diverse set of Escherichia coli phages interact with cell debris generated either by sonication or by phage-induced lysis. We find that most phages exhibit receptor-binding activity toward cell debris, but irreversible binding is weak, and in some cases the binding is mostly transient and reversible. In contrast, a subset of phages, including those utilizing BtuB as a receptor, exhibit strong, irreversible binding to sonicated debris. We consider the evolutionary and ecological consequences of the interactions of different phages with cell debris.