IDENTIFICATION AND CHARACTERIZATION OF NOVEL ADHESINS IN MYCOBACTERIUM AVIUM SUBSP. PARATUBERCULOSIS

MARIANA VIALE; GABRIELA ECHEVERRIA; MON, ML; ROMANO, MI; ANDREA GIOFFRÉ

Sydney

Congreso; 11th International Congress of Paratuberculosis; 2012

Asociación internacional de paratuberculosis

The pathogenic potential of Mycobacterium avium subsp. paratuberculosis (MPTB) and the molecularbasis for its intestinal tropism are still unclear. Binding and ingestion of MPTB by host cells is fibronectin (FN) dependent and there is a family of proteins present in several species of mycobacteria that allows their attachment and internalization by epithelial cells via interaction with FN. Secott et al. (2002) demonstrated that the interaction between FN and FAP-P facilitates attachment and internalization of MPTB by epithelial cells. Dheenadhayalan et al. (2002) characterized MPTB Ag85complex, consisting of Ag85A, Ag85B and Ag85C, and observed in silico that the three conserved regions involved in FNbinding in other mycobacteria were also present in N-terminal regions of 85A, B and C of MPTB.Additionally, Kuo et al. (2012) recently showed experimentally that the members of this family possess the ability to specifically interact with FN. Thus, it is important the identification of adhesion molecules to understand the pathogenesis of MPTB. This could be useful to propose new preventive strategies against paratuberculosis. The aim of this study was to identify and characterize FN binding-cell wall proteins from MPTB. To accomplish this, a cell wall protein fraction was obtained and resolved by 2D-electrophoresis. Theidentity of the spots was obtained by MALDI-TOF MS and a homology searching was performed to find ifthe proteins indentified had FN-binding orthologues in other organisms