Chapter 15.2, Problem 22AQP

(a)

Summary Introduction

To determine:

The amino acids specified by the given bacterial mRNA sequences.

Introduction:

Amino acids are the crucial component of all protein molecules. All amino acids are specified by a unique codon called genetic code. The genetic code is made up of nucleotide bases that form in groups to specify amino acids. The genetic code consists of a triplet code, in which three nucleotides encode a single amino acid in a protein. The genetic code has sixty-one codons that specify the twenty amino acids. The three codons are stop codons or nonsense codons that do not encode any amino acid.

Explanation of Solution

By referring to figure 15.10 in the textbook, amino acids can be determined for the given mRNA sequence.

(a) ${\text{5}}^{\text{'}}{\text{-AUGUUUAAAUUUAAAUUUUGA-3}}^{\text{'}}$

${\text{5}}^{\text{'}}\text{-}\underset{\text{Met}}{\text{AUG}}\text{-}\underset{\text{Phe}}{\text{UUU}}\text{-}\underset{\text{Lys}}{\text{AAA}}\text{-}\underset{\text{Phe}}{\text{UUU}}\text{-}\underset{\text{Lys}}{\text{AAA}}\text{-}\underset{\text{Phe}}{\text{UUU}}\text{-}\underset{\text{stop}}{\text{UGA}}{\text{-3}}^{\text{'}}$

The amino acids that are specified by this bacterial mRNA sequenceare:

Methionine-Phenylalanine-Lysine-Phenylalanine-Lysine-Phenylalanine-Stop

(b)

Summary Introduction

To determine:

The amino acids specified by the given bacterial mRNA sequences.

Introduction:

Amino acids are the crucial component of all protein molecules. All amino acids are specified by a unique codon called genetic code. The genetic code is made up of nucleotide bases that form in groups to specify amino acids. The genetic code consists of a triplet code, in which three nucleotides encode a single amino acid in a protein. The genetic code has sixty-one codons that specify the twenty amino acids. The three codons are stop codons or nonsense codons that do not encode any amino acid.

Explanation of Solution

By referring to figure 15.10 in the textbook, amino acids can be determined for the given mRNA sequence.

(b) ${\text{5}}^{\text{'}}{\text{-AGGGAAAUCAGAUGUAUAUAUAUAUAUGA-3}}^{\text{'}}$

${\text{5}}^{\text{'}}\text{-}\underset{\text{Arg}}{\text{AGG}}\text{-}\underset{\text{Glu}}{\text{GAA}}\text{-}\underset{\text{Ile}}{\text{AUC}}\text{-}\underset{\text{Arg}}{\text{AGA}}\text{-}\underset{\text{Cys}}{\text{UGU}}\text{-}\underset{\text{Ile}}{\text{AUA}}\text{-}\underset{\text{Tyr}}{\text{UAU}}\text{-}\underset{\text{Ile}}{\text{AUA}}\text{-}\underset{\text{Tyr}}{\text{UAU}}{\text{-GA-3}}^{\text{'}}$

The amino acids that are specified by this bacterial mRNA sequence are:

Arginine-Glutamate-Isoleucine-Arginine-Cysteine-Isoleucine-Tyrosine-Isoleucine Tyrosine. The last two nucleotides, GA will not encode any amino acid because it does not form a full codon.

(c)

Summary Introduction

To determine:

The amino acids specified by the given bacterial mRNA sequences.

Introduction:

Amino acids are the crucial component of all protein molecules. All amino acids are specified by a unique codon called genetic code. The genetic code is made up of nucleotide bases that form in groups to specify amino acids. The genetic code consists of a triplet code, in which three nucleotides encode a single amino acid in a protein. The genetic code has sixty-one codons that specify the twenty amino acids. The three codons are stop codons or nonsense codons that do not encode any amino acid.

Explanation of Solution

By referring to figure 15.10 in the textbook, amino acids can be determined for the given mRNA sequence.

(c) ${\text{5}}^{\text{'}}{\text{-UUUGGAUUGAGUGAAACGAUGGAUGAAAGAUUUCUCGCUUGA-3}}^{\text{'}}$

$\left(\begin{array}{l}{\text{5}}^{\text{'}}\text{-}\underset{\text{Phe}}{\text{UUU}}\text{-}\underset{\text{Gly}}{\text{GGA}}\text{-}\underset{\text{Leu}}{\text{UUG}}\text{-}\underset{\text{Ser}}{\text{AGU}}\text{-}\underset{\text{Glu}}{\text{GAA}}\text{-}\underset{\text{Thr}}{\text{ACG}}\text{-}\underset{\text{Met}}{\text{AUG}}\text{-}\underset{\text{Asp}}{\text{GAU}}\text{-}\\ \underset{\text{Glu}}{\text{GAA}}\text{-}\underset{\text{Arg}}{\text{AGA}}\text{-}\underset{\text{Phe}}{\text{UUU}}\text{-}\underset{\text{Leu}}{\text{CUC}}\text{-}\underset{\text{Ala}}{\text{GCU}}\text{-}\underset{\text{stop}}{\text{UGA}}{\text{-3}}^{\text{'}}\end{array}\right)$

The amino acids that are specified by this bacterial mRNA sequence are:

Phenylalanine-Glycine-Leucine-Serine-Glutamate-Threonine-Methionine-Aspartate-Glutamate-Arginine-Phenylalanine-Leucine-Alanine-Stop.

(d)

Summary Introduction

To determine:

The amino acids specified by the given bacterial mRNA sequences.

Introduction:

Amino acids are the crucial component of all protein molecules. All amino acids are specified by a unique codon called genetic code. The genetic code is made up of nucleotide bases that form in groups to specify amino acids. The genetic code consists of a triplet code, in which three nucleotides encode a single amino acid in a protein. The genetic code has sixty-one codons that specify the twenty amino acids. The three codons are stop codons or nonsense codons that do not encode any amino acid.

Explanation of Solution

By referring to figure 15.10 in the textbook, amino acids can be determined for the given mRNA sequence.

(d) ${\text{5}}^{\text{'}}{\text{-GUACUAAGGAGGUUGUAUGGGUUAGGGGACAUCAUUUUGA-3}}^{\text{'}}$

$\left(\begin{array}{l}{\text{5}}^{\text{'}}\text{-}\underset{\text{Val}}{\text{GUA}}\text{-}\underset{\text{Leu}}{\text{CUA}}\text{-}\underset{\text{Arg}}{\text{AGG}}\text{-}\underset{\text{Arg}}{\text{AGG}}\text{-}\underset{\text{Leu}}{\text{UUG}}\text{-}\underset{\text{Tyr}}{\text{UAU}}\text{-}\underset{\text{Gly}}{\text{GGG}}\text{-}\\ \underset{\text{Leu}}{\text{UUA}}\text{-}\underset{\text{Gly}}{\text{GGG}}\text{-}\underset{\text{Asp}}{\text{GAC}}\text{-}\underset{\text{Ile}}{\text{AUC}}\text{-}\underset{\text{Ile}}{\text{AUU}}\text{-}\underset{\text{Leu}}{\text{UUG}}\text{-}\underset{}{\text{A}}{\text{-3}}^{\text{'}}\end{array}\right)$

The amino acids that are specified by this bacterial mRNA sequence are:

Valine-Leucine-Arginine-Arginine-Leucine-Tyrosine-Glycine-Leucine-Glycine-Aspartate-Isoleucine-Isoleucine-Leucine.

Conclusion:

Each codon consists of three nucleotides that encode a particular amino acid. There is one initiation codon AUG and three termination codons, UAA, UGA, and UAG.