Normal Sickle CelI Disease Partial Amino Acid Sequence for Beta Globin: Pro-Glu-Glu Pro Val Glu Hemoglobin Molecule: Red Blood Cell: Figure 9. Changes to the beta-globin subunit of hemoglobin in...

Extracted text: Normal Sickle CelI Disease Partial Amino Acid Sequence for Beta Globin: Pro-Glu-Glu Pro Val Glu Hemoglobin Molecule: Red Blood Cell: Figure 9. Changes to the beta-globin subunit of hemoglobin in sickle cell disease and the functional consequence for red blood cells. Image modified from here in accordance with Creative Commons License. Watch this video about sickle cell anemia, then answer the questions below. 3. Figure 9 illustrates the molecular cause of the most common version of sickle cell disease. A valine is substituted for a glutamate in hemoglobin in sickle cell disease. Which levels of protein structure are altered, and specifically, which types of interaction are likely to be changed in determining the shape of the protein? Explain your answer. 4. Normal red blood cells can easily travel through blood vessels, whereas sickle- shaped red blood cells get stuck. This is the basis of sickle cell anemia. What does this tell you about the relationship between the sequence of amino acids, the shape of the protein and its function in a cell/organism? The table below has been provided for you to summarize what you found for each level of protein structure through this activity. Types of bonds generated to reinforce that level Groups of the amino acids that contribute to Key terms/ideas that define that level Protein Structure Level the bonds


Extracted text: QUATERNARY STRUCTURE One final level of structure exists for some, but not all, proteins. This is called quaternary structure. Proteins that have quaternary structure are formed from two or more polypeptides that assemble into one active structure. The different polypeptides in a protein with quaternary structure are often called subunits. These subunits may be identical or different. One example of a protein with quaternary structure is hemoglobin, the protein that transports oxygen in our blood. The structure of hemoglobin is shown in Figure 8. B- Fe2+ Heme a Figure 8. Quaternary structure of hemoglobin with labeled subunits. Note: each subunit contains one non-protein heme group complexed to an oxidized iron atom (Fe2+). These “prosthetic groups" are required for carrying oxygen in the blood. Modified from this link under Creative Commons license. Answer the below questions on quaternary structure in your own document. 1. Based on your interpretation of Figure 9, how many subunits does hemoglobin contain? Are they all the same or different? 2. Which types of interactions do you think stabilize the quaternary structure of proteins that have this level of structure? (Hint: this is not any different from the interactions you identified in tertiary structure, except for the fact that multiple polypeptides are involved).