Question

Aerotolerant Anaerobe only produce superoxide dismutase, but not catalase. Why?

Answer 1

The enzyme catalase is produced by bacteria that respire using oxygen and protects them from the toxic by products of oxygen metabolism.

Aerotolerant anerobes use fermentation to produce ATP. They donot utilize oxygen and donot require it as the terminal electron acceptor. So they donot have catalase enzyme. But they can protect themselves from reactive oxygen species so have superoxide dismutase.

Since aerotolerant anerobes cannot use oxygen for its growth but can tolerate its presence so they produce superoxide dismutase only but not catalase.

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