Question

The sequence below corresponds to the first 15 bases of the open reading frame of the E.coli cysS gene. For each of the following mutation sequences, determine the amino acid sequence encoded by the 15 bases, identify whether the mutation is a transition, transversion, insertion, deletion. Also identify whether the mutation is a missense, nonsense, silent or frame-shift mutation. 5' ATG CTA AAA ATC TTC a. 5' ATG CTA AAG ATC TTC b. 5' ATG CTA TAA ATC TTC c. 5' ATG CTA AAA AAT CTT d. 5' ATG CGA AAA ATC TTC

Answer 1

a) silent mutation (Transition mutation )

b) nonsense mutation. (Transversion mutation)

c) frame-shift mutation ( insertion mutation )

d) missense mutation ( transversion mutation )

Step-by-step explanation:

For 5' ATG CTA AAA ATC TTC

The WT sequence ; M L I K F

a) For 5' ATG CTA AAG ATC TTC

The Mutated sequence : M L K I F

The mutation here is a silent mutation i.e. Transition mutation takes places at the 9th position of the nucleotide sequence

b) For . 5' ATG CTA TAA ATC TTC

The Mutated sequence ; M L STOP

The mutation here is a nonsense mutation. that is a Transversion mutation as well

c) For 5' ATG CTA AAA AAT CTT

The mutated sequence is MLKNL

The mutation here is a frame-shift mutation ( i.e. also insertion mutation

d) For 5' ATG CGA AAA ATC TTC

The mutated sequence is MRKIF

The mutation here is a missense mutation ( i.e. also transversion mutation )