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(a)
To predict: The amino acid sequences of peptides formed by ribosomes in response to the given
Introduction:
The biosynthesis of protein is done with the help of messenger RNA (mRNA). The proteins are encoded by the genetic codons. The ribosomes are present in biological decoding machinery. These ribosomes link specific amino acids in a sequence which is specified by codons.
(a)
Explanation of Solution
Explanation:
The amino acids specify by
GGU CAG UCG CUC CUG AUU
Gly–Gln–Ser–Leu–Leu–Ile
Here, the codon GGU specifies the glycine amino acid, CAG specifies glutamine, UCG specifies serine, CUC and CUG both specify amino acid leucine. The amino acid Isoleucine is specified by the codon AUU. Thus, the amino acids which specify the mRNA sequence are glycine, glutamine, leucine, serine and isoleucine.
(b)
To determine: The amino acid sequences of peptides formed by ribosomes in response to the given
Introduction:
Biological decoding machinery consists of the ribosomes. The similar types of genetic codes are present in all living organisms. The total numbers of codons present in individuals are 64 in number which includes the 20 amino acids
(b)
Explanation of Solution
Explanation:
The amino acids specified by the mRNA sequences are as follow:
UUG GAU GCG CCA UAA UUU GCU
Leu – Asp – Ala – Pro – stop (UAA is a stop codon)
The codon UUG specifies theleucine amino acid, GAU specifies aspartic acid, GCG specifies alanine, CCA specify amino acid proline and UAA act stop codon which also stops the further protein synthesis. Thus, the amino acids which are specified by codons are leucine, aspartic acid, alanine and proline. The codon UAA is the stop codon which stops the synthesis of protein.
(c)
To determine: The amino acid sequences of peptides formed by ribosomes in response to the given mRNA sequences CAUGAUGCCUGUUGCUAC.
Introduction:
There are some amino acids which are encoded by more than one codon. All the living organisms consist of similar type of genetic codes. The proteins are synthesized by the genetic codons.
(c)
Explanation of Solution
Explanation:
The amino acids specify by mRNA sequences are as follow:
CAU GAU GCC UGU UGC UAC
His–Asp–Ala–Cys–Cys–Tyr
The codon CAU specifies the histidine amino acid, GAU specifies aspartic acid, GCC specifies alanine, both UGC codons specify amino acid cysteine and UAC specifies tyrosine. Thus, the mRNA sequence specifies the amino acid histidine, aspartic acid, alanine, cysteine and tyrosine.
(d)
To determine: The amino acid sequences of peptides formed by ribosomes in response to the given mRNA sequences AUG GAC GAA..
Introduction:
These ribosomes link specific amino acids in a sequence which is specified by codons. Individuals consists of total numbers of 64 codons are which includes the 20 amino acids. This is because there are some amino acids which are coded by more than one codon.
(d)
Explanation of Solution
Explanation:
The amino acids specify by mRNA sequences are as follow:
AUG GAC GAA
Met–Asp–Glu in eukaryotes and fMet–Asp–Glu in prokaryotes
AUG specifies the methionine amino acid, GAC specifies aspartic acid, GAA specifies glutamate. In prokaryotes, AUG specifies methyl methionine. Thus, the amino acids methionine, aspartic acid and glutamate are coded by the codons present in mRNA sequence.
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Chapter 27 Solutions
SAPLINGPLUS FOR PRINCIPLES OF BIOCHEMIS
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- a. Draw the Krebs Cycle and show the entry points for the amino acids Alanine,Glutamic Acid, Asparagine, and Valine into the Krebs Cycle. (Include name of Enzymes involved) b. How many rounds of Krebs will be required to waste all Carbons of Glutamic Acid as CO2? (Show by drawing out the mechanism that occurs)arrow_forwardThe malate-aspartate shuttle allows malate to be exchanged for aspartate acrossthe inner mitochondrial membrane. (a) Describe the role of the malate-aspartate shuttle in liver cells under HIGHblood glucose conditions. Be sure to explain your answer. (b) Describe the role of the malate-aspartate shuttle in liver cells under LOW blood + glucose conditions.arrow_forward(a) Write out the net reaction, calculate ∆E ̊' for the reaction, and calculate the standard free-energy change (∆G°') for the overall oxidation/reduction reaction. (h) How many moles of ATP could theoretically be generated per mole of FADH2 oxidized by this reaction, given a ∆G ̊' of ATP synthesis of + 31 kJ/mol? How many moles of ATP could be generated per mole of FADH2 oxidized by this reaction under more typical cellular conditions (where ∆G' of ATP hydrolysis is ~ -50 kJ/mol)? Be sure to show your work and explain your answer.arrow_forward
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- Sodium fluoroacetate (FCH2CO2Na) is a very toxic molecule that is used as rodent poison. It is converted enzymatically to fluoroacetyl-CoA and is utilized by citrate synthase to generate (2R,3S)-fluorocitrate. The release of this product is a potent inhibitor of the next enzyme in the TCA cycle. Show the mechanism for the production of fluorocitrate and explain how the molecule acts as a competitive inhibitor. Predict the effect on the concentrations of TCA intermediates.arrow_forwardIn three separate experiments, pyruvate labeled with 13C at C-1, C-2, or C-3 is introduced to cells undergoing active metabolism. Trace the fate of each carbon through the TCA cycle and show when each of these carbons produces 13CO2. Glucose is similarly labeled at C-2 with 13C. During which reaction will this labeled carbon be released as 13CO2?arrow_forwardPlease draw this out and show how they react with electron flow! TPP is also utilized in transketolase reactions in the PPP. Give a mechanism for the TPP-dependent reaction between Xylulose-5-phosphate and Ribose-5-Phosphate to yield the products of Glyceraldehyde-3-phosphate and Sedoheptulose-7-Phosphate.arrow_forward
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