Chapter 22, Problem 60P

Derive the amino acid sequence that is coded for by each mRNA sequence.

1. 5 AAA CCC UUU UGU 3
2. 5 CCU UUG GAA GUA CUU 3
3. 5 GGG UGU AUG CAC CGA UUG 3

Interpretation Introduction

(a)

Interpretation:

Amino acid sequence responsible for the 5 AAA CCC UUU UGU 3 mRNA code should be derived.

Concept Introduction:

Genetic code − DNA and RNA transform genetic information of the living cells through triplet code, which is a sequence of three nucleotides on DNA or RNA molecules codes for a specific amino acid in protein synthesis.

Answer to Problem 60P

Lys-Pro-Phe-Cys

Explanation of Solution

Codons are written from 5 prime end (5) to 3 prime end (3) of mRNA. There is a unique triplet representation for a particular amino acid. Below mentioned table represent the relationship between nucleotides and amino acids.

The Genetic Code- Triplets in Messenger RNA

First Base (5' end)	Second Base								Third Base (3' end)
	U		C		A		G
U	UUU	Phe	UCU	Ser	UAU	Tyr	UGU	Cys	U
	UUC	Phe	UCC	Ser	UAC	Tyr	UGC	Cys	C
	UUA	Leu	UCA	Ser	UAA	Stop	UGA	Stop	A
	UUG	Leu	UCG	Ser	UAG	Stop	UGG	Trp	G
C	CUU	Leu	CCU	Pro	CAU	His	CGU	Arg	U
	CUC	Leu	CCC	Pro	CAC	His	CGC	Arg	C
	CUA	Leu	CCA	Pro	CAA	Gln	CGA	Arg	A
	CUG	Leu	CCG	Pro	CAG	Gln	CGG	Arg	G
A	AUU	Ile	ACU	Thr	AAU	Asn	AGU	Ser	U
	AUC	Ile	ACC	Thr	AAC	Asn	AGC	Ser	C
	AUA	Ile	ACA	Thr	AAA	Lys	AGA	Arg	A
	AUG	Met	ACG	Thr	AAG	Lys	AGG	Arg	G
G	GUU	Val	GCU	Ala	GAU	Asp	GGU	Gly	U
	GUC	Val	GCC	Ala	GAC	Asp	GGC	Gly	C
	GUA	Val	GCA	Ala	GAA	Glu	GGA	Gly	A
	GUG	Val	GCG	Ala	GAG	Glu	GGG	Gly	G

According to the above table; one amino acid has several triplets, but triplet code is unique for amino acid.AAA triplet is unique for Lysine. CCC triplet is unique for Proline. UUU triplet is unique for phenylalanine. UGU triplet is unique for cysteine.

Therefore, Lys-Pro-Phe-Cys is the amino acid sequence for 5 AAA CCC UUU UGU 3.

Interpretation Introduction

(b)

Interpretation:

Amino acid sequence responsible for the 5 CCU UUG GAA GUA CUU 3 mRNA code should be derived.

Concept Introduction:

Genetic code − DNA and RNA transform genetic information of the living cells through triplet code, which is a sequence of three nucleotides on DNA or RNA molecules codes for a specific amino acid in protein synthesis.

Answer to Problem 60P

Pro-Leu-Glu-Val-Leu

Explanation of Solution

Codons are written from 5 prime ends (5) to 3 prime ends (3) of mRNA. There is a unique triplet representation for a particular amino acid. The below-mentioned table represents the relationship between nucleotides and amino acids.

The Genetic Code- Triplets in Messenger RNA

First Base (5' end)	Second Base								Third Base (3' end)
	U		C		A		G
U	UUU	Phe	UCU	Ser	UAU	Tyr	UGU	Cys	U
	UUC	Phe	UCC	Ser	UAC	Tyr	UGC	Cys	C
	UUA	Leu	UCA	Ser	UAA	Stop	UGA	Stop	A
	UUG	Leu	UCG	Ser	UAG	Stop	UGG	Trp	G
C	CUU	Leu	CCU	Pro	CAU	His	CGU	Arg	U
	CUC	Leu	CCC	Pro	CAC	His	CGC	Arg	C
	CUA	Leu	CCA	Pro	CAA	Gln	CGA	Arg	A
	CUG	Leu	CCG	Pro	CAG	Gln	CGG	Arg	G
A	AUU	Ile	ACU	Thr	AAU	Asn	AGU	Ser	U
	AUC	Ile	ACC	Thr	AAC	Asn	AGC	Ser	C
	AUA	Ile	ACA	Thr	AAA	Lys	AGA	Arg	A
	AUG	Met	ACG	Thr	AAG	Lys	AGG	Arg	G
G	GUU	Val	GCU	Ala	GAU	Asp	GGU	Gly	U
	GUC	Val	GCC	Ala	GAC	Asp	GGC	Gly	C
	GUA	Val	GCA	Ala	GAA	Glu	GGA	Gly	A
	GUG	Val	GCG	Ala	GAG	Glu	GGG	Gly	G

According to the above table; one amino acid has several triplets, but triplet code is unique for an amino acid. CCU triplet is unique for Proline. UUG triplet is unique for Leucine. GAA triplet is unique for Glutamic acid. GUA triplet is unique for Valine. CUU triplet is unique for Leucine.

Therefore, Pro-Leu-Glu-Val-Leu is the amino acid sequence for 5 CCU UUG GAA GUA CUU 3.

Interpretation Introduction

(c)

Interpretation:

Amino acid sequence responsible for the 5 GGG UGU AUG CAC CGA UUG 3 mRNA code should be derived.

Concept Introduction:

Genetic code − DNA and RNA transform genetic information of the living cells through triplet code, which is a sequence of three nucleotides on DNA or RNA molecules codes for a specific amino acid in protein synthesis.

Answer to Problem 60P

Gly-Cys-Met-His-Arg-Leu

Explanation of Solution

Codons are written from 5 prime ends (5) to 3 prime ends (3) of mRNA. There is a unique triplet representation for a particular amino acid. The below-mentioned table represents the relationship between nucleotides and amino acids.

The Genetic Code- Triplets in Messenger RNA

First Base (5' end)	Second Base								Third Base (3' end)
	U		C		A		G
U	UUU	Phe	UCU	Ser	UAU	Tyr	UGU	Cys	U
	UUC	Phe	UCC	Ser	UAC	Tyr	UGC	Cys	C
	UUA	Leu	UCA	Ser	UAA	Stop	UGA	Stop	A
	UUG	Leu	UCG	Ser	UAG	Stop	UGG	Trp	G
C	CUU	Leu	CCU	Pro	CAU	His	CGU	Arg	U
	CUC	Leu	CCC	Pro	CAC	His	CGC	Arg	C
	CUA	Leu	CCA	Pro	CAA	Gln	CGA	Arg	A
	CUG	Leu	CCG	Pro	CAG	Gln	CGG	Arg	G
A	AUU	Ile	ACU	Thr	AAU	Asn	AGU	Ser	U
	AUC	Ile	ACC	Thr	AAC	Asn	AGC	Ser	C
	AUA	Ile	ACA	Thr	AAA	Lys	AGA	Arg	A
	AUG	Met	ACG	Thr	AAG	Lys	AGG	Arg	G
G	GUU	Val	GCU	Ala	GAU	Asp	GGU	Gly	U
	GUC	Val	GCC	Ala	GAC	Asp	GGC	Gly	C
	GUA	Val	GCA	Ala	GAA	Glu	GGA	Gly	A
	GUG	Val	GCG	Ala	GAG	Glu	GGG	Gly	G

According to the above table; one amino acid has several triplets, but triplet code is unique for an amino acid. GGG triplet is unique for Glycine. UGU triplet is unique for Cystine. AUG triplet is unique for Methionine. CAC triplet is unique for Histidine. CGA triplet is unique for Arginine. UUG triplet is unique for Leucine.

Therefore, Gly-Cys-Met-His-Arg-Leu is the amino acid sequence for 5 GGG UGU AUG CAC CGA UUG 3