Tolerance of Salt and Extreme pH
Similar to the temperature behavior seen in Appendix 16, there can be Cardinal salt concentrations. This is seen in Appendix 17. Tolerance to pH is seen in Appendix 18.
Other ways to Classify Microorganisms
Aerobic
Obligate – must have O2.
Facultative – O2 is not required but they will grow better with O2.
Microaerophilic – O2 required but in very small amounts.
Anaerobic
Aerotolerant – O2 not required and not metabolized.
Obligate – O2 is poisonous