Transducing phage can be used to map bacterial genes. Phages are collected from an E. coli donor strain of genotype cys+leu+thr+ and used to transduce a recipient strain of genotype cys-leu-thr-. Initially the treated recipient population is plated on a minimal medium supplemented with leucine and threonine. Many colonies are obtained.
a. What are the possible genotypes of these colonies?
These colonies are then replica plated onto three different media: 1) minimal plus threonine only. 2) minimal plus leucine only, and 3) minimal. What genotypes could, in theory, grow on these three media?
Of the original colonies, 56% are observed to grow on medium 1, 5% on medium 2, and no colonies on medium 3. What are the actual genotypes of the colonies on media 1, 2, and 3?
Draw a map showing the order of the three genes and which of the outer genes is closer to the middle gene.
Transducing phage can be used to map bacterial genes. Phages are collected from an E. coli donor strain of genotype cys+leu+thr+ and used to transduce a recipient strain of genotype cys-leu-thr-. Initially the treated recipient population is plated on a minimal medium supplemented with leucine and threonine. Many colonies are obtained.
a. What are the possible genotypes of these colonies?
These colonies are then replica plated onto three different media: 1) minimal plus threonine only. 2) minimal plus leucine only, and 3) minimal. What genotypes could, in theory, grow on these three media?
Of the original colonies, 56% are observed to grow on medium 1, 5% on medium 2, and no colonies on medium 3. What are the actual genotypes of the colonies on media 1, 2, and 3?
Draw a map showing the order of the three genes and which of the outer genes is closer to the middle gene.
