A mutant bacterial cell has a defective aminoacyl-tRNA synthetase that attaches a lysine to tRNAs with the anticodon AAA instead of the normal phenylalanine. The consequence of this for the cell will be that ________.
A) none of the proteins in the cell will contain phenylalanine
B) proteins in the cell will include lysine instead of phenylalanine at amino acid positions specified by the codon UUU
C) the cell will compensate for the defect by attaching phenylalanine to tRNAs with lysine-specifying anticodons
D) the ribosome will skip a codon every time a UUU is encountered

Question

Quizplus · Accepted Answer

The mutant bacterial cell will incorporate lysine instead of phenylalanine at amino acid positions specified by the codon UUU, since the defective aminoacyl-tRNA synthetase will attach lysine to tRNAs with the anticodon AAA instead of phenylalanine. This will result in a varied and possibly dysfunctional protein structure and function.

A Mutant Bacterial Cell Has a Defective Aminoacyl-TRNA Synthetase That