CHEM120 OL, Week 7 Lab
OL Lab 13: Protein Synthesis
Learning Objectives
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Explain the translation process from mRNA to amino acid
Explain post-translational modification of proteins
Explain protein synthesis processing in the ribosome
Explain the primary, secondary, tertiary and quaternary structures of protein
Explain the basic principles of mass spectrometry (MALDI-TOF)
Introduction
In the Protein Synthesis lab, you will learn about the difference between protein
synthesis in prokaryote (using E. coli) and eukaryote (using Chinese hamster ovarian
(CHO) cells).
Prepare recombinant Erythropoietin and use the mass spectrometer
Your first task in the lab will be to prepare recombinant erythropoietin (EPO) that is
transfected into E. coli and CHO cells. The lab assistant will prepare the recombinant
EPO and you will measure the mass to charge ratio using a mass spectrometer. Not
sure how to handle the mass spectrometer? No worries! You can just take out your
labpad and find an animated video to learn the basics.
Study the translation process from mRNA to amino acids
You will also learn about the translation process from mRNA to amino acids and how
amino acids are assembled to proteins. A 3D animation will describe how codons are
translated into amino acids, how these amino acids are joined together by peptide
bonds creating a primary structure of protein, and how the primary structure is folded
into secondary, tertiary and quaternary structure.
Investigate doping in bike athletes
In the last part of the Protein Synthesis lab, you will use mass spectrometry to
investigate if any athletes are using recombinant human erythropoietin (rhEPO) as a
doping substance. You will do so by collaborating with the doping agent who collects
urine samples at a large bicycle race.
Will you be able to detect if any of the athletes are using doping?
Part 1: Complete Labster Lab: Protein Synthesis
Part 2: Report and Reflection
Purpose: Describe in complete sentences and in your own words, the purpose of this
experiment.
The purpose of this experiment was to understand chronic renal disease, RNA, DNA,
peptide bonds, protein structures, and genetic code.
CHEM120 OL, Week 7 Lab
Observations: Record three observations from the simulation.
Translation is the synthesis of polypeptide using information in the mRNA.
Transcription is synthesis of RNA using information in the DNA.
DNA is the hereditary material of all living organisms.
Answer the questions below:
1. In your own words, describe the process of gene expression beginning from the
nucleus to the formation of the polypeptide sequence.
The process of gene expression involves the synthesis of mRNA from DNA by
the process of transcription which take place inside the nucleus in case of
eukaryotes and cytoplasm in case of prokaryotes. In eukaryotes, the genetic
material or DNA is present inside the nucleus while as in prokaryotes, the DNA is
present directly in the cytoplasm as they lack a well-defined nucleus. The mRNA
produced is then translated into polypeptides/proteins (protein synthesis) and this
protein represents the functional product of the gene and performs the specific
functions assigned to it. In this way the information contained in the DNA is
decoded and expressed inside the cells for carrying out the life processes.
2. Complete the table below:
Nucleic acid
DNA
Amine Bases Present
Adenine, Guanine,
Cytosine, and Thymine.
RNA
Adenine, Guanine,
Cytosine, and Uracil.
Location(s) in cell
Prokaryotes- cytoplasm.
Eukaryotes- Nucleus.
Chloroplast
Mitochondrial matrix
Made in nucleus later
transported cytoplasm.
3. Assume that RNA Polymerase will read the parental strand of DNA given here
and write the mRNA sequence that would result: - TATGCTTCCGTA mRNA:
AUACGAAGGCAU
CHEM120 OL, Week 7 Lab
4. Reflection: Consider what you learned from this simulation. Reflect on three to
four key concepts that you learned in this lab exercise. How could the lessons
learned in this virtual lab relate to a real world situation in the community/world or
your future career? Be specific in your answer (this should require 5-10
sentences).
RNA does not have Thymine. DNA does not have Uracil. In eukaryotes, the genetic
material or DNA is present inside the nucleus. Prokaryotic does not have a nucleus, so
the genetic information is stored in cytoplasm. In real world situation, this information
can be used to teach other about how to differentiate organisms.
CHEM120 OL, Week 7 Lab
Grading Rubric:
Activity
Part I
Part II
Deliverable
Complete simulation and answer all questions
Complete lab report and answer questions
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Total
Points
9
9
Purpose (1 point)
Observations (3 points)
Questions (3 points)
Reflection (2 points)
Complete all lab activities
18