title: Evaluation of the kinetics and mechanism of action of anti-integration host factor-mediated disruption of bacterial biofilms.
abstract: The extracellular polymeric substance produced by many human pathogens during biofilm formation often contains extracellular DNA (eDNA). Strands of bacterial eDNA within the biofilm matrix can occur in a lattice-like network wherein a member of the DNABII family of DNA-binding proteins is positioned at the vertex of each crossed strand. To date, treatment of all biofilms tested with antibodies directed against one DNABII protein, Integration Host Factor (IHF), results in significant disruption. Here, using non-typeable Haemophilus influenzae as a model organism, we report that this effect was rapid, IHF-specific and mediated by binding of transiently dissociated IHF by anti-IHF even when physically separated from the biofilm by a nucleopore membrane. Further, biofilm disruption fostered killing of resident bacteria by previously ineffective antibiotics. We propose the mechanism of action to be the sequestration of IHF upon dissociation from the biofilm eDNA, forcing an equilibrium shift and ultimately, collapse of the biofilm. Further, antibodies against a peptide positioned at the DNA-binding tips of IHF were as effective as antibodies directed against the native protein. As incorporating eDNA and associated DNABII proteins is a common strategy for biofilms formed by multiple human pathogens, this novel therapeutic approach is likely to have broad utility.
authors: Center for Microbial Pathogenesis, The Research Institute at Nationwide Children's Hospital, 700 Children's Drive, Columbus, OH, 43205, USA; Department of Pediatrics, The Ohio State University College of Medicine, Columbus, OH, 43210, USA.
authors: M Elizabeth
authors: ME
authors: Brockson
authors: Laura A
authors: LA
authors: Novotny
authors: Elaine M
authors: EM
authors: Mokrzan
authors: Sankalp
authors: S
authors: Malhotra
authors: Joseph A
authors: JA
authors: Jurcisek
authors: Rabia
authors: R
authors: Akbar
authors: Aishwarya
authors: A
authors: Devaraj
authors: Steven D
authors: SD
authors: Goodman
authors: Lauren O
authors: LO
authors: Bakaletz
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology; D000906:Antibodies / Q000494:pharmacology*; D018441:Biofilms / Q000187:drug effects*; D004269:DNA, Bacterial / Q000378:metabolism; D018604:Epitope Mapping; D006193:Haemophilus influenzae / Q000187:drug effects / Q000502:physiology*; D054884:Host-Pathogen Interactions / Q000187:drug effects; D006801:Humans; D034982:Integration Host Factors / Q000378:metabolism*; D007700:Kinetics
chemical_list: D000900:Anti-Bacterial Agents; D000906:Antibodies; D004269:DNA, Bacterial; D034982:Integration Host Factors