Study of respiratory symptoms among sputum positive

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classic endotoxic lipopolysaccharide associated with gram negative
bacteria. However, similarties to gram negative cell walls include the
paucity of peptidoglycan and the fact that mycobacterial cell walls contain
meso-diaminopimelic acid (DAP) and an outer lipid barrier. This
mycobacterial cell walls exhibit many of the characteristics of gram
positive bacteria and some qualities of gram negative bacteria, but most
importantly, possess their own unique features (McNeil et al., 1994).
The cell wall of mycobacteria is composed ofthree layers enclosing
a plasma membrane, which is also a three- layered structure. Chemically,
the wall is very complex, and unlike of either gram positive or gram
negative organisms, it contains an abundance of complex lipophilic
macromolecules, many of which are unique to the organism and are
biologically very active (Brennan, 1989).
The most distinctive attribute ofthe mycobacterial cell envelope is
the mycolic acid. In case of mycobacterium tuberculosis, the mycolic acid
contain 70 to 90 carbon atoms (Minnikin and Good Fellow, 1980). They
constitute more than 50% by weight ofthe mass ofisolated cell envelops
and apparently interact via powerful hydrophobic binding to form a lipid
shell surrounding the organism. This property is undoubtedly responsible
for the lipid barrier and consequent endogenous resistance to know drugs
(McNeil et aI., 1994).
Lipids account for approximately 60% ofthe dry weight ofthe wall
and cofer properties that enable the organism to resist adverse
environmental conditions. The backbone ofthe mycobacterial cell wall is a
covalent structure consisting of two polymers covalently linked by
phosphodiester bonds, a peptidoglycan and an arabinogalactan, to this
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