Interaction of Mycobacterium tuberculosis ESAT-6 protein with ADAM9 protein
Keywords:
ESAT-6 protein, ADAM9 protein, Mycobacterium tuberculosis, yeast two-hybrid, GST pull-down assay, surface plasmon resonance binding.Abstract
The ESAT-6 protein of Mycobacterium tuberculosis (M. tb) is an important structural and functional protein, which
has been known to be involved in the virulence, pathogenesis as well as proliferation of the pathogen; however,
how ESAT-6 protein interact with host protein is still unclear. In order to study the function of the M. tuberculosis
protein ESAT-6 in the infection process, we searched for host proteins that interact with this secreted
mycobacterial protein. Using a yeast two-hybrid system we identified the ADAM9 (a disintegrin and
metalloprotease) protein as a candidate to interact with ESAT-6. This interaction was further confirmed by protein
overlay and surface plasmon resonance binding assay using recombinant ESAT-6 and ADAM9, and by GST pulldown analysis of the mycobacterial expressed ESAT-6 and ADAM9. The interaction domains were localized by
yeast two-hybrid studies using truncated derivatives of ESAT-6 protein. The C-terminus of ESAT-6 binds to the
ADAM9, Thus, the host protein ADAM9 represents a possible cellular receptor for the mycobacterial protein ESAT6. This is the first report demonstrating the interaction of ADAM9 with a structural protein of M. tb.
