Their hearts became noticeably more flexible and could process oxygen more efficiently. (functionalhealthnews.com)
I'm pretty sure there are some bacteria that can process oxygen into... something different... I would have to do some desk research on that. (wattsupwiththat.com)
Many antibiotics work by disrupting bacterial metabolism, so adjustments to how the germs process oxygen can also strengthen their resistance to drugs. (discovermagazine.com)