Question

You've collected a soil sample from an unexplored island and cultured a new bacterial species by growing it on complete media. Being a wild-type strain, you assume it is prototrophic. What would you do to determine whether this is true?

Assume you find that your new bacterial strain is auxotrophic. What might you do to determine what kind of auxotroph it is?

Answer 1

Firstly, bacteria is cultured in a general media, most of the microbiologist use agar to culture bacteria. It will be easy to determine the bacteria if it is feeded every possible things to survive, either it is liquid or solid in the culture plate.

From the above information given, if the bacteria assumed is prototrophic which grows in a very minimal medium or sometime without the supplement. The prototrophs are wild-type hence it is also known as self sufficient producer.

BUdr (bromodeoxyuridine) when added to the minimal medium as followed by the incubation, to prototrophic cell DNA is added, which help to continue the growth, though the nutrilites are absent. This helps the above statement is correct about the prototrophs which are cultured and bacteria is grown.

Auxotroph mutants as compared to prototrophs do not show any growth in the minimal media, as the above given information to determine the type of auxotrophs which are commonly used in filamentous fungi and the genes is required. Autotrophs needs to be on nutrients otherwise it do not grow further.

This helps to determine the auxotrophs bacterial strain.

The diagram attached below shows the protrophs, which is grown by adding minimal media

Whereas, auxotrophs do not show growth on minimal media.