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Name: Yvonne
Status: Student
Grade:  9-12
Location: DE
Country: United States
Date: October 2006

Why are anaerobes unable to reproduce in the presence of oxygen? Why will they die?

Oxygen breaks down into what are known as free radicals which are toxic to all cells. Organisms that live in an oxygen atmosphere have enzymes that can turn the free radicals into something less toxic. Anaerobes don't have these enzymes and are killed by the free radicals.


Excellent question!

One theory is that anaerobes lack enzymes like catalase and super-oxide dismutase which can break down hydrogen peroxide and other toxic oxygen compounds which form during cell metabolism in an aerobic environment.

Ron Baker, PhD.

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