Question

SULR as the fow thermometer un 2. When a protein denatures in a cell, what causes it to aggregate with other denatured cell proteins? (2pts) 3. How might a heat shock protein help a protein fold correctly in a cell under normal conditions? (2 pts). 4. The bacterial GroEL heat-shock protein and the plant Rubisco assembly proteins are said to be homologous proteins. What is it about these proteins that has caused them to be described as members of the same protein family and suggests that they have the same function? 5. A molecular chaperone named GroEL is found in the cytoplasm of the bacterium E. coli. An homologous protein, the function of which is thought to aid in Rubisco assembly, is found in plant chloroplasts. Why would it not be surprising to find a protein so similar to GroEL, a prokaryotic protein, in these eukaryotic cell organelles? (2pts) 6. Describe the evidence that convinced investigators that chaperones do not assist the assembly of already-folded subunits into larger complexes but that they instead assist polypeptide chain folding. (3pts)

Answer 1

Question 2

When the protein denature in a cell, it means it looses the various type of bonds that were present in the 3D structure of the plant. When the protein get denature , protein is susceptible to misfolding or unfolding. When this denatured protein get interact with another denatured protein, they aggregate in which the hydrophobic group present in the R (side-chain) of amino acid may interact with exposed hydrophobic side chain of another amino acid.

Question 3

Heat shock protein are also known as Chaperons protein. These proteins help in the forming of correct bonds between the amino acid present in the newly synthesized polypeptide chain. The heat shock proteins stabilize the 3D structure of the protein by giving its correct binding between the side-chain of amino acid.

Question 4

The GroEL is a heat shock protein that give stability to the protein in high temperature conditions where protein could be denature easily. Similarly, the Rubisco is an enzyme that catalyze the first step of Calvin cycle and this enzyme is also very high temperature resistant enzyme and do not get denature at high temprtature.

Question 5

It is not suprising that two proteins present in prokaryotes and other in eukaryotes are so similar because all organism have evolved from one common ancestor. The prokaryotes have evolved first and eukaryotes later. But still there are many proteins that are similar in both group of organism because of common evolution.