Protein Synthesis Lab-ster

DNA is the molecule of heredity that contains instructions to build proteins. IN 1958, Francis Crick described the central dogma of molecular biology explaining the process of gene expression. What do A and B represent in the image?

'A' is transcription and 'B' is translation

The glycosylation site are marked with glycan diagram. Drag the blue box on the top right graph to view all the alycan diagram. Based on he mass spectrometry results, how many glycosylation sites exists in rhEPO-CHO?

4

I forgot the next question but the answer is:

Secondary structure

Bases on the mass spectrometer result, what is the mass difference between rhEPO expressed in CHO and E. coli? Check the computer for the mass spectrometry graph results of each.

12 kDa

Bases on the mass spectrometry result, the masses of rhEPO expressed in CHO and E. coli are 30 kDa and 8kDa, respectively. We also know that the EPO proteins expressed in mammalian cells are glycosylated. Therefore, we can say that what weight percentage of rhEPO expressed in CHO are polysaccharides.

40%

Which is the correct mRNA sequence resulting from the EPO gene transcription process? Use the VIEW IMAGE button to help you.

5'- AUU ACA AUG GGG GUG CAC GAA UGU CCU - 3'

The tRNA shown in the diagram will be able to form a base pair interaction with which mRNA?

5'-AGU

The erythropoietin protein is 193 amino acids long. With this information, how many nucleic acids are there in the mRNA including the initiator and terminator codons?

582

The mRNA strand is synthesized in the 5' to 3' direction. The circles in the image indicate the chemical group to which the next base is attached. Which image has the circle in the correct position?

C

Glycosylation sites are marked with a diagram of glycan. Based on the mass spectrometry results, rhEPO is glycosylated in which expression system?

CHO

What is the name of each sequence of three nitrogen containing bases of RNA that codes for one amino acid?

Codon

Recombinant proteins produce by E.coli cells are not glycosylated. This is because E. coli cells do not possess which organelle?

Golgi apparatus

After answering the questions above click on HYPOTHESIS A, because that's what I picked and I have the answers to those questions. If you pick Hypothesis B, you are on your own from here on out!

Hypothesis A: Mammalian expression system can produce biologically active and stable.

In mass spectrometry protein molecules are separated based on their mass to charge ratio. The data is recorded in a histogram for analysis. Which of these histograms are NOT coherent with the mass spectrometry principle?

II, III, IV

What is the correct amino acid translated from the resulting mRNA?

MGVHECP

Mass spectrometry identifies molecules based on what?

Mass and charge

MALDI is an abbreviation for what?

Matrix- assisted laser desorption/ionization.

Protein synthesis is performed by an RNA- protein complex called the ribosome. As you can see in the image, a ribosome is comprised of 3 sites called E, P and A. To which site does tRNA add its amino acid to the polypeptide chain?

P

Amino acids are linked by a specific type of covalent bond. The reaction of this bond produces one water molecule. This bond links multiple amino acids together, what is it called?

Peptide bonds

The macromolecule ionization method, such as MALDI MS, allows us to obtain a peptide mass fingerprint, or PMF, that can be used to do what?

Predict the identity of an unknown protein.

A sequence of amino acids, or a polypeptide, grows from the N- terminus to the C- terminus. This polypeptide chain represents the primary structure of a protein. The linear sequence of amino acids within a protein is considered the _____structure of the protein.

Primary

EPO can increase production of energy (ATP) by increasing production of what?

Red blood cells

Click the view image button to view a eukaryotic cell. Where do eukaryotic cells synthesize proteins and which number represents this organelle in the image?

Ribosomes, 2

An EPO gene is 582 bp long. This is the down stream section of the coding sequence for the erythropoietin mRNA: 5'-ACA GGG GAC AGA UGA- 3' Downstream means near the 3' end, so notice that the first codon is not methionine. What is the correct amino acid sequence?

TGDR

The biosafety cabinet is important for physical containment. IN this lab we will use a biosafety cabinet class II. Who or what does a level II biosafety cabinet protect?

The personnel, the experiment, and the environment.

DNA and mRNA synthesis proceeds in the 5' to 3' direction. What do 5' and 3' refer to?

The position of a carbon atom in the sugar backbone.

If X,Y, and Z refer to the parts of a mass spectrometer that perform different processes such that: - X detects the number of different ions. - Y is where ion production from the sample takes place. -Z separates ions with different mass to charge ratios in which order do X, Y, and Z occur?

Y, Z, then X

Are mammalian expression systems better than bacterial systems for the production of biologically active and stable erythropoietin?

Yes, erythropoietin is the best expressed in mammalian cells.

I forgot this question but I think it asks something about what three types of RNA cooperate to perform translation

tRNA, mRNA, rRNA

Compare the sample results from each athlete with control results. there are two controls: a positive control that contains rhEPO only and a negative control that contains only urine. Which athlete is using rhEPO? Use the buttons on the computer screen to analyze the graphs.

A

Proteins sample are mixed with a matrix prior to analysis. What is the function of a matrix in MALDI MS analysis?

Ensures ionization of protein molecules

Two basic types of protein secondary structures are helix and sheet. The alpha helix is a right handed coil. The beta sheet can formed be two or more segments of polypeptide chain lying side by side. The entire folded protein 3D structure is known as tertiary structure. The main two secondary structures of proteins are alpha helix and beta sheet which are represented respectively by which two letters in the image?

B and A

Bacterial cells often cannot produce recombinant proteins that are identical to their wild type. Why is this?

Bacteria lack the machinery for making post-translational modifications.

Have a look at this simplified depiction of a DNA strand using the VIEW IMAGE button. Which strand is the template strand?

Bottom

You can observe the main difference between DNA and RNA by clicking on the view image button. Which statement is true?

DNA has no hydroxyl group on the second carbon.