title: Noroviral p-particles as an in vitro model to assess the interactions of noroviruses with probiotics.
abstract: Noroviruses (NoVs) are the main etiologic agents of acute epidemic gastroenteritis and probiotic bacteria have been reported to exert a positive effect on viral diarrhea. The protruding (P) domain from NoVs VP1 capsid protein has the ability to assemble into the so-called P-particles, which retain the binding ability to host receptors. We purified the P-domains from NoVs genotypes GI.1 and GII.4 as 6X(His)-tagged proteins and determined that, similar to native domains, they were structured into P-particles that were functional in the recognition of the specific glycoconjugated receptors, as established by surface plasmon resonance experiments. We showed that several lactic acid bacteria (probiotic and non-probiotic) and a Gram-negative probiotic strain have the ability to bind P-particles on their surfaces irrespective of their probiotic status. The binding of P-particles (GI.1) to HT-29 cells in the presence of selected strains showed that bacteria can inhibit P-particle attachment in competitive exclusion experiments. However, pre-treatment of cells with bacteria or adding bacteria to cells with already attached P-particles enhanced the retention of the particles. Although direct viral binding and blocking of viral receptors have been postulated as mechanisms of protection against viral infection by probiotic bacteria, these results highlight the need for a careful evaluation of this hypothesis. The work presented here investigates for the first time the probiotic-NoVs-host interactions and points up the NoVs P-particles as useful tools to overcome the absence of in vitro cellular models to propagate these viruses.
authors.affiliation: Laboratory of Lactic Acid Bacteria and Probiotics, Biotechnology Department, Institute of Agrochemistry and Food Technology (IATA-CSIC), Valencia, Spain.
authors.forename: Antonio
authors.initials: A
authors.lastname: Rubio-del-Campo
authors.affiliation: Laboratory of Lactic Acid Bacteria and Probiotics, Biotechnology Department, Institute of Agrochemistry and Food Technology (IATA-CSIC), Valencia, Spain.
authors.forename: José M
authors.initials: JM
authors.lastname: Coll-Marqués
authors.affiliation: Laboratory of Lactic Acid Bacteria and Probiotics, Biotechnology Department, Institute of Agrochemistry and Food Technology (IATA-CSIC), Valencia, Spain.
authors.forename: María J
authors.initials: MJ
authors.lastname: Yebra
authors.affiliation: Department of Microbiology and Ecology, Faculty of Medicine, University of Valencia, Valencia, Spain.
authors.forename: Javier
authors.initials: J
authors.lastname: Buesa
authors.affiliation: Laboratory of Lactic Acid Bacteria and Probiotics, Biotechnology Department, Institute of Agrochemistry and Food Technology (IATA-CSIC), Valencia, Spain.
authors.forename: Gaspar
authors.initials: G
authors.lastname: Pérez-Martínez
authors.affiliation: Laboratory of Lactic Acid Bacteria and Probiotics, Biotechnology Department, Institute of Agrochemistry and Food Technology (IATA-CSIC), Valencia, Spain.
authors.forename: Vicente
authors.initials: V
authors.lastname: Monedero
authors.affiliation: Laboratory of Lactic Acid Bacteria and Probiotics, Biotechnology Department, Institute of Agrochemistry and Food Technology (IATA-CSIC), Valencia, Spain.
authors.forename: Jesús
authors.initials: J
authors.lastname: Rodríguez-Díaz
mesh_terms: D036022:Capsid Proteins / Q000737:chemistry* / Q000378:metabolism / Q000648:ultrastructure; D020895:Enterocytes / Q000821:virology; D004926:Escherichia coli / Q000502:physiology* / Q000821:virology; D019073:HT29 Cells; D054884:Host-Pathogen Interactions; D006801:Humans; D007780:Lacticaseibacillus casei / Q000502:physiology* / Q000821:virology; D029322:Norovirus / Q000502:physiology*; D019936:Probiotics / Q000737:chemistry*; D011485:Protein Binding; D011991:Receptors, Virus / Q000378:metabolism; D020349:Surface Plasmon Resonance; D053585:Virus Attachment
chemical_list: D036022:Capsid Proteins; D011991:Receptors, Virus