In: Biology
Obligate anaerobes are those microorganisms which can not
survive in the presence of oxygen but can generate ATP and grow
well in the absence of oxygen. They die in presence of oxygen
because they lack some defense mechanism which aerobic
microorganisms' posses when they react with oxygen present in air
it gets converted into superoxide ion which then forms H2O2 when
superoxide ion reacts with water.H2O2 is highly reactive and cause
real damages to the cell. In the case of aerobic microorganisms,
they contain catalase, peroxidase, and superoxide dismutase.
Catalase prevents the formation of H2O2.On the other hand,
superoxide dismutase prevents the formation of oxygen radicals
which is formed by oxidation of superoxide ion and prevents the
cell from oxidative damage of oxygen radicals. That is why aerobic microorganisms survive
in the presence of oxygen because they have peroxidases, catalase,
and superoxide dismutase.