You isolate a strain of E. coli in which there is a mutation in a gene encoding an important polypeptide.   The wild type polypeptide is 541 amino acids long.  The mutation changes the nucleotide sequence encoding amino acid 102 from a UGU (which encodes the amino acid cysteine) to UGA (a stop codon).   The mutant strain grows only 10% as fast as the wild type strain.

Q1: How will the mutant polypeptide differ from the wild type polypeptide? And what do we mean by "wild type"?

Q2: There are multiple genes for each tRNA used in E. coli; how might the effects of the mutation described above be partially reversed by a mutation in a tRNA gene?

Q3: What effects would such a mutant tRNA gene have on a wild type cell?

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