title: S-layer proteins from Lactobacillus sp. inhibit bacterial infection by blockage of DC-SIGN cell receptor.
abstract: Many species of Lactobacillus sp. possess Surface(s) layer proteins in their envelope. Among other important characteristics S-layer from Lactobacillus acidophilus binds to the cellular receptor DC-SIGN (Dendritic Cell-Specific Intercellular adhesion molecule-3-Grabbing Non-integrin; CD209), which is involved in adhesion and infection of several families of bacteria. In this report we investigate the activity of new S-layer proteins from the Lactobacillus family (Lactobacillus acidophilus, Lactobacillus brevis, Lactobacillus helveticus and Lactobacillus kefiri) over the infection of representative microorganisms important to human health. After the treatment of DC-SIGN expressing cells with these proteins, we were able to diminish bacterial infection by up to 79% in both gram negative and mycobacterial models. We discovered that pre-treatment of the bacteria with S-layers from Lactobacillus acidophilus and Lactobacillus brevis reduced bacteria viability but also prevent infection by the pathogenic bacteria. We also proved the importance of the glycosylation of the S-layer from Lactobacillus kefiri in the binding to the receptor and thus inhibition of infection. This novel characteristic of the S-layers proteins may contribute to the already reported pathogen exclusion activity for these Lactobacillus probiotic strains; and might be also considered as a novel enzymatic antimicrobial agents to inhibit bacterial infection and entry to host cells.
authors: Laboratorio de Bacterias Gram Positivas, Departamento de Química Biológica-IQUIBICEN, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires-CONICET, Argentina. Electronic address: m.pradoacosta@gmail.com.
authors: Mariano
authors: M
authors: Prado Acosta
authors: Laboratorio de Bacterias Gram Positivas, Departamento de Química Biológica-IQUIBICEN, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires-CONICET, Argentina.
authors: Sandra M
authors: SM
authors: Ruzal
authors: Laboratorio de Virología, Departamento de Química Biológica-IQUIBICEN, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires-CONICET, Argentina. Electronic address: scordo@qb.fcen.uba.ar.
authors: Sandra M
authors: SM
authors: Cordo
mesh_terms: D016475:3T3 Cells; D000818:Animals; D000900:Anti-Bacterial Agents / Q000494:pharmacology; D001422:Bacterial Adhesion / Q000187:drug effects; D001424:Bacterial Infections / Q000188:drug therapy*; D015815:Cell Adhesion Molecules / Q000378:metabolism*; D006031:Glycosylation / Q000187:drug effects; D006801:Humans; D007778:Lactobacillus / Q000737:chemistry*; D037181:Lectins, C-Type / Q000378:metabolism*; D008562:Membrane Glycoproteins / Q000494:pharmacology / Q000627:therapeutic use*; D051379:Mice; D011956:Receptors, Cell Surface / Q000378:metabolism*; D000099215:DC-Specific ICAM-3 Grabbing Nonintegrin
chemical_list: D000900:Anti-Bacterial Agents; D015815:Cell Adhesion Molecules; D037181:Lectins, C-Type; D008562:Membrane Glycoproteins; D011956:Receptors, Cell Surface; D000099215:DC-Specific ICAM-3 Grabbing Nonintegrin; C055764:S-layer proteins
keywords: DC-SIGN; Lactobacillus; S-layer