mohammad tabish ahmed - eTheses Repository - University of ...

Chapter 6
Section 6.1: Testing the ability of M. tuberculosis Cpn60.1 to function in M.
smegmatis
Background
As discussed in the introductory chapter and in chapter 3, it is known that the main housekeeping
chaperonin in both M. tuberculosis and M. smegmatis is Cpn60.2, while Cpn60.1 has
evolved to perform alternate functions.
Our current understanding of the functions of
MsCpn60.1 implicates its role in biofilm maturation for M. smegmatis while the MtbCpn60.1
chaperonin has been shown to play a role in granuloma formation during tuberculosis (Hu et
al., 2008, Kim et al., 2003, Ojha et al., 2005).
Biofilm formation is an important aspect of many pathogenic bacteria, including E. coli, V.
cholerae, H. influenze, and P. aeroginosa (Hall-Stoodley & Stoodley, 2009, Bjarnsholt et al.,
2010, Fux et al., 2005). These bacteria make use of the biofilms to provide them with
protection from the diverse environmental and nutrient conditions, while also providing them
with the means to protect themselves from the effects of antibiotics (Bjarnsholt et al., 2010,
Hall-Stoodley et al., 2004, Cernohorska & Votava, 2010).
In M. smegmatis, it has been shown that the loss of biofilm maturation can be caused by
deleting the groEL1 (Mscpn60.1) gene which results in the lack of association between
MsCpn60.1 and KasA (Ojha et al., 2005). KasA is a component of the fatty acid synthase
(FAS)-II complex which is required for the elongation of mycolic acid chains. So the deletion
209