2 replies to this topic

[somu]

helloooo

Does anyone having idea that E.coli culture can give slight yellowish colonies on Macckonkey agar . I havent seen such type of colonies in past. Presently I am trying to demonstrate purity of one of the E. coli culture. All other test like Indole test is showing E. coli , but on Macconkey few colonies are yellowish. Does anyone has idea about this. Your suggestions and observations are necessary to come out with conclusion.

Thanks

[GeorgeWolff]

"Few of the colonies"?  So not all? You sure it's a pure culture?

[Tanja N]

Our experience is that E.coli  DH5α and NM522 cells are yellowish on MACCONKEY agar.

Regards,
T