title: Description of a novel adhesin of Mycobacterium avium subsp. paratuberculosis.
abstract: The binding and ingestion of Mycobacterium avium subsp. paratuberculosis (MAP) by host cells are fibronectin (FN) dependent. In several species of mycobacteria, a specific family of proteins allows the attachment and internalization of these bacteria by epithelial cells through interaction with FN. Thus, the identification of adhesion molecules is essential to understand the pathogenesis of MAP. The aim of this study was to identify and characterize FN binding cell wall proteins of MAP. We searched for conserved adhesins within a large panel of surface immunogenic proteins of MAP and investigated a possible interaction with FN. For this purpose, a cell wall protein fraction was obtained and resolved by 2D electrophoresis. The immunoreactive spots were identified by MALDI-TOF MS and a homology search was performed. We selected elongation factor Tu (EF-Tu) as candidate for further studies. We demonstrated the FN-binding capability of EF-Tu using a ligand blot assay and also confirmed the interaction with FN in a dose-dependent manner by ELISA. The dissociation constant of EF-Tu was determined by surface plasmon resonance and displayed values within the μM range. These data support the hypothesis that this protein could be involved in the interaction of MAP with epithelial cells through FN binding.
authors.affiliation: Instituto de Biotecnología, Instituto Nacional de Tecnología Agropecuaria, 1686 Hurlingham, Buenos Aires, Argentina.
authors.forename: Mariana Noelia
authors.initials: MN
authors.lastname: Viale
authors.affiliation: Instituto de Biotecnología, Instituto Nacional de Tecnología Agropecuaria, 1686 Hurlingham, Buenos Aires, Argentina.
authors.forename: Gabriela
authors.initials: G
authors.lastname: Echeverria-Valencia
authors.affiliation: Instituto de Estudios de la Inmunidad Humoral (IDEHU), Facultad de Farmacia y Bioquímica, Universidad de Buenos Aires, 1113 Ciudad Autónoma de Buenos Aires, Argentina.
authors.forename: Pablo
authors.initials: P
authors.lastname: Romasanta
authors.affiliation: Instituto de Biotecnología, Instituto Nacional de Tecnología Agropecuaria, 1686 Hurlingham, Buenos Aires, Argentina.
authors.forename: María Laura
authors.initials: ML
authors.lastname: Mon
authors.affiliation: Instituto de Estudios de la Inmunidad Humoral (IDEHU), Facultad de Farmacia y Bioquímica, Universidad de Buenos Aires, 1113 Ciudad Autónoma de Buenos Aires, Argentina.
authors.forename: Marisa
authors.initials: M
authors.lastname: Fernandez
authors.affiliation: Instituto de Estudios de la Inmunidad Humoral (IDEHU), Facultad de Farmacia y Bioquímica, Universidad de Buenos Aires, 1113 Ciudad Autónoma de Buenos Aires, Argentina.
authors.forename: Emilio
authors.initials: E
authors.lastname: Malchiodi
authors.affiliation: Instituto de Biotecnología, Instituto Nacional de Tecnología Agropecuaria, 1686 Hurlingham, Buenos Aires, Argentina.
authors.forename: María Isabel
authors.initials: MI
authors.lastname: Romano
authors.affiliation: Instituto de Biotecnología, Instituto Nacional de Tecnología Agropecuaria, 1686 Hurlingham, Buenos Aires, Argentina.
authors.forename: Andrea Karina
authors.initials: AK
authors.lastname: Gioffré
authors.affiliation: Instituto de Biotecnología, Instituto Nacional de Tecnología Agropecuaria, 1686 Hurlingham, Buenos Aires, Argentina.
authors.forename: María de la Paz
authors.initials: Mde L
authors.lastname: Santangelo
mesh_terms: D018829:Adhesins, Bacterial / Q000235:genetics* / Q000302:isolation & purification; D015180:Electrophoresis, Gel, Two-Dimensional; D004847:Epithelial Cells / Q000378:metabolism / Q000382:microbiology; D005353:Fibronectins / Q000378:metabolism*; D006801:Humans; D009162:Mycobacterium avium / Q000235:genetics* / Q000472:pathogenicity; D010283:Paratuberculosis / Q000235:genetics* / Q000382:microbiology / Q000473:pathology; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
chemical_list: D018829:Adhesins, Bacterial; D005353:Fibronectins