Mycobacterium tuberculosis
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Transcript Mycobacterium tuberculosis
Mycobacterium tuberculosis Characteristics
Mycobacterium tuberculosis is a
non-motile, acid-fast, obligate aerobe
bacterium that resists decolorization
with acidified organic solvents
Considered hydrophobic due to the
high lipid content in the cell wall
It is not considered gram positive
nor gram negative, but instead is
classified as acid-fast
M. tuberculosis is manifested more
often in HIV positive patients due to a
weakened immune system
High resistance to drug therapy
http://www.turbosquid.com/3d-models/3d-mycobacterium-tuberculosis-model/683105
Contagious for several weeks after
drug therapy is initiated
A. Ryan F2013
Modified by DYH
M. tuberculosis Virulence
M. tuberculosis does not have the classical
virulence factors
Lipoamide dehydrogenase (Lpd) - helps
the bacterium resist host-reactive nitrogen
intermediates
Antigen 85 complex: group of
secretedproteins that bind fibronectin;
may help in protecting the bacterium from
the immune system
Slow generation time: immune system
may not readily recognize the bacterium
and therefore not be able to kill it
High lipid concentration of cell wall:
enables the bacterium to be resistant to
many antimicrobial agents, acidic and
alkaline compounds, and osmotic lysis
http://medicineworld.org/images/blogs/11-2007/mycobacterium-tuberculosis-299290.jpg
Cord factor: known to be toxic to humans
and other mammalian cells
A. Ryan F2013
Modified by DYH