dc.description.abstract | Tuberculosis (TB) infection is one of the major
public health problems in developing country
including Indonesia. The endemic of TB infection
caused by Mycobacterium tuberculosis became
worse because of the multidrug-resistant TB (MDRTB).
M. tuberculosis had special feature which is
its cell wall or envelope that consists of complex
lipids, lipoglycans and peptidoglycans (Forrelad,
2013). The cell wall consisted of two layers, the
inner and the outer. The inner consisted of
peptidoglycan sacculus veiled by
mycolylarabinogalactan polysaccharide layer. The
outer envelope consisted of trehalose 6,6′dimycolate
(TDM; cord factor) which was
synthesized by fibronectin binding protein (fbp)/
antigen 85 (Ag85) complex (Elamin, 2011).
The Ag85 complex was a 30–32 kDa protein
consisting of three proteins (Ag85A, Ag85B, and
Ag85C). It had several functions, including
enzymatic mycolyl-transferase activity for coupling
of mycolic acids to cell wall arabinogalactan, cord
factor biogenesis (trehalose-dimycolate), and had
capacity to bind to fibronectin and elastin of the
extracellular matrix proteins (Huygen, 2014). This
protein were encoded by three paralogous genes
located in different regions of the bacterial
genome (D’Souza, 2003). The Ag85 complex was
the major secreted protein of M. tuberculosis cell
culture besides of its association with bacterial
surface. It had essential role in the pathogenesis of
tuberculosis. The ability of this protein to bind
fibronectin promoted M. tuberculosis adhesion to
the mucosal surface, thus facilitating the bacteria
to entry into the host cell. However, the main role
of it to the virulence of M. tuberculosis was the
ability to synthesis of cell wall lipids (Forrelad,
2013). | en_US |