Suppose that a researcher is looking for met^- strains of E. coli. She compares two plates. One plate has colonies growing on complete media. The other plate has colonies growing on methionine-deficient media. How can the researcher determine which colonies are met^-?

Question

Quizplus · Accepted Answer

The correct method to identify met^- strains of E. coli, which are unable to synthesize methionine, is by replica plating the colonies from the complete media (where all strains can grow because the media supplies all necessary nutrients) onto methionine-deficient media (minimal media). Strains that cannot grow on the minimal media, due to the lack of methionine, are identified as met^-.

Suppose That a Researcher Is Looking for Met- Strains of E

Suppose That a Researcher Is Looking for Met^- Strains of E