How do the oxygen requirements of Streptococcus and Escherichia differ? Which one is an aerotolerant anaerobe?

Answer 1

Odd - I've looked up wikipedia and looked up my microbiology text. Neither of them explicitly go into the oxygen requirements of these species except my micro text says Streptococci are faculatative organisms (ie. they can grow with or without oxygen).

This doesn't really sound like an aerotolerant anaerobe (and I always believed Strep to be aerobic).

Oxford Textbook of Medicine describes Streptococci as:

"...Gram-positive cocci that form chains and grow in air, though some of the may require the addition of CO2 to do this."

It makes no comment on the growth or culture of E coli

Answer 2

As a dental professional, I know that certain bacteria needs oxygen to live... and there are some, more destructive bacterias that can live without O2. They can live under the gums, become destructive to the bones and gums, hence, one of the many reasons to visit the dentist on a regular basis. :)

Sorry my answer isn't as good as the guy above me. :)