Question

What are the different types of bacterial mutants: auxotrophic, carbon source, antibiotic-resistant, and temperature sensitive? How could you select any of these mutants? In what kind of medium would they grow/not grow? In what kind of medium could you distinguish/not distinguish them from wild type bacteria?

Answer 1

Auxotrophic mutants are the mutants that require some additional nutrients for it's complete growth as they itself cannot synthesized that particular nutrient so it is imp to provide them supplement in their media for their proper growth.

They can be selected by keeping particular nutrients to be deficient in their media so that population of mutants will not grow in such media which then be isolated from other wild population that can easily grow even in deficiency of that nutrient.

Carbon source mutants are the bacterial mutants that cannot grow in media with carbon source like glucose, lactose, galactose.

They can be selected by adding carbon source to the media so mutants population will be easily recognised from other live population of bacteria.

Antibiotics resistant mutants are the bacterial mutants that becomes resistant to certain antibiotics like ampicillin , tetracycline etc if added in media . That means they can grow even in presence of antibiotics.

They can be selected by adding that particular antibiotics to the media so that only mutants will be able to survive and other will die.

Temperature sensitive bacterial mutants are the bacteria that become temperature labile or u can say cannot tolerate high temperature for survival.

By giving high temperature condition to population of bacterial colonies we can select the temperature sensitive bacteria.