title: Low-level predation by lytic phage phiIPLA-RODI promotes biofilm formation and triggers the stringent response in Staphylococcus aureus.
abstract: An important lesson from the war on pathogenic bacteria has been the need to understand the physiological responses and evolution of natural microbial communities. Bacterial populations in the environment are generally forming biofilms subject to some level of phage predation. These multicellular communities are notoriously resistant to antimicrobials and, consequently, very difficult to eradicate. This has sparked the search for new therapeutic alternatives, including phage therapy. This study demonstrates that S. aureus biofilms formed in the presence of a non-lethal dose of phage phiIPLA-RODI exhibit a unique physiological state that could potentially benefit both the host and the predator. Thus, biofilms formed under phage pressure are thicker and have a greater DNA content. Also, the virus-infected biofilm displayed major transcriptional differences compared to an untreated control. Significantly, RNA-seq data revealed activation of the stringent response, which could slow down the advance of the bacteriophage within the biofilm. The end result would be an equilibrium that would help bacterial cells to withstand environmental challenges, while maintaining a reservoir of sensitive bacterial cells available to the phage upon reactivation of the dormant carrier population.
authors.affiliation: Instituto de Productos Lácteos de Asturias (IPLA-CSIC), Paseo Río Linares s/n 33300, Villaviciosa, Asturias, Spain.
authors.forename: Lucía
authors.initials: L
authors.lastname: Fernández
authors.affiliation: Instituto de Productos Lácteos de Asturias (IPLA-CSIC), Paseo Río Linares s/n 33300, Villaviciosa, Asturias, Spain.
authors.forename: Silvia
authors.initials: S
authors.lastname: González
authors.affiliation: Instituto de Productos Lácteos de Asturias (IPLA-CSIC), Paseo Río Linares s/n 33300, Villaviciosa, Asturias, Spain.
authors.forename: Ana Belén
authors.initials: AB
authors.lastname: Campelo
authors.affiliation: Instituto de Productos Lácteos de Asturias (IPLA-CSIC), Paseo Río Linares s/n 33300, Villaviciosa, Asturias, Spain.
authors.forename: Beatriz
authors.initials: B
authors.lastname: Martínez
authors.affiliation: Instituto de Productos Lácteos de Asturias (IPLA-CSIC), Paseo Río Linares s/n 33300, Villaviciosa, Asturias, Spain.
authors.forename: Ana
authors.initials: A
authors.lastname: Rodríguez
authors.affiliation: Instituto de Productos Lácteos de Asturias (IPLA-CSIC), Paseo Río Linares s/n 33300, Villaviciosa, Asturias, Spain.
authors.forename: Pilar
authors.initials: P
authors.lastname: García
mesh_terms: D001433:Bacteriolysis; D018441:Biofilms / Q000254:growth & development*; D020869:Gene Expression Profiling; D015964:Gene Expression Regulation, Bacterial; D006790:Host-Parasite Interactions; D017423:Sequence Analysis, RNA; D013204:Staphylococcus Phages / Q000254:growth & development*; D013211:Staphylococcus aureus / Q000502:physiology* / Q000821:virology*; D013312:Stress, Physiological