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Write the full names of four amino acids that can be found as part of an alpha-h

ID: 280588 • Letter: W

Question

Write the full names of four amino acids that can be found as part of an alpha-helix that is inserted into the membrane.

Explain what happens to the hydrophilic peptide bonds when an alpha-helix is formed, and why this is advantageous for membrane spanning proteins.

4. a) Write the full names of four amino acids that can be found as part of an alpha-helix that is inserted into the membrane. (2 points each; 8 points total) iv b) Explain what happens to the hydrophilic peptide bonds when an alpha-helix is formed, and why this is advantageous for membrane spanning proteins. (5 points) 5. List two mechanisms used by the cell to confine proteins to distinct membrane domains. (6 points) 6. In class we talked about how AG for the creation of ATP from ADP and inorganic phosphate is +7.3 kcal/mol. a) Given the AG° values below for the hydrolysis of the types of phosphate bonds, circle the type(s) of phosphate bonds that can be coupled to make ATP creation energetcially favorable in the cell. (2 points) Type of phosphate bond AG° value phosphoanhydride bond7.3 kcal/mol enol phosphate bond phosphoester bond anhydride bond to carbon -11.7 kcal/mol 14.8 kcal/mol 3.3 kcalmol b) Explain why you circled the bond type(s) above. (4 points)

Explanation / Answer

4) a) i) Methionine

ii) Alanine

iii) leucine

iv) Glutamate

4) b) The hydrophilic peptide bomds will form hydrogen bonds with one another to form the alpha helix. Because they bond with each other they do not contact the hydrophobic hydrocarbon tails found in the phospholipids of the membrane.