For a different experiment you are growing up Saccharomyces

For a different experiment you are growing up Saccharomyces cerivisiae instead of E.coli. The measured OD is 0.89. A) In order to calculate the concentration of the Saccharomyces cerivisiae culture, can you use the equation that you use to calculate the concentration of an E.coli culture? If yes or no, give a detailed explanation. B) Does E.coli or Saccharomyces cerivisiae have a shorter generation time? Give a detailed explanation!

Solution

A ) In order to calculate the concentration of the Saccharomyces cerevisiae culture, one can not use the equation that one use to calculate the concentration of an E.coli culture as 1 OD of E.coli culture corresponds to 1 x 10⁹ CFU/ml, while 1 OD of Saccharomyces cerevisiae corresponds to 1 x 10⁷ CFU/ml.

B) Generation time is the doubling time, so the E.coli has doubling time of 20 minutes, while S.cerevisiae has doubling time of 90 minutes.