Facultative anaerobes

Facultative anaerobes are microorganisms that can survive with or without oxygen. They prefer oxygen when it's available because it allows them to produce energy more efficiently. However, if there’s no oxygen, they can switch to an alternative way of producing energy that doesn't require oxygen. This flexibility helps them adapt to different environments, such as the human body or various soil conditions. Examples include bacteria like Escherichia coli and certain yeasts. Their ability to thrive in both oxygen-rich and oxygen-poor settings makes them highly versatile and resilient.