Description of a novel adhesin of Mycobacterium avium subsp. paratuberculosis

VIALE, MARIANA; GIOFFRÉ, ANDREA; ECHEVERRIA, GABRIELA; ROMASANTA, PABLO; MON, MARIA LAURA; FERNANDEZ, MARISA; MALCHIODI, EMILIO; ROMANO, MARÍA ISABEL; SANTANGELO, MARÍA DE LA PAZ

BioMed Research International

Hindawi

Año: 2014

The binding and ingestion of Mycobacterium avium subsp. paratuberculosis (MAP) by 21 host cells is Fibronectin (FN) dependent. In several species of mycobacteria, a specific 22 family of proteins allows the attachment and internalization of these bacteria by 23 epithelial cells through interaction with FN. Thus, the identification of adhesion 24 molecules is essential to understand the pathogenesis of MAP. 25 2 The aim of this study was to identify and characterize FN binding-cell wall proteins of 26 MAP. We searched for conserved adhesins within a large panel of surface immunogenic 27 proteins of MAP and investigated a possible interaction with FN. For this purpose, a 28 cell wall protein fraction was obtained and resolved by 2D-electrophoresis. The 29 immunoreactive spots were identified by MALDI-TOF MS and a homology search was 30 performed. We selected Elongation factor Tu (EF-Tu) as candidate for further studies. 31 We demonstrated the FN-binding capability of EF-Tu using a Ligand Blot Assay and 32 also confirmed the interaction with FN in a dose-dependent manner by ELISA. The 33 dissociation constant of EF-Tu was determined by Surface Plasmon Resonance, and 34 displayed values within the ?ÝM range. This data support the hypothesis that this protein 35 could be involved in the interaction of MAP with epithelial cells through FN binding.