24. Anfinsen demonstrated the renaturation of the protein RNase in vitro. Why wo

Question

24. Anfinsen demonstrated the renaturation of the protein RNase in vitro. Why would the protein not refold were removed after the reducing agent was removed? a. The protein would not fully unfold (denature). b. Urea would participate in weak bonding interactions with RNase, preventing oxidation of Cys c. Disulfide bonds are not positioned correctly unless weak bonding interactions are present. d. the completely unfolded enzyme, with all -S-s-bonds broken, is still enzymatically active. e. Contaminants in the RNase preparation would form covalent bonds with the protein, preventing reactivation 25. Which ligand binds tightest? a. ligand A, with a Ke 10'M b, ligand B, with a Ka-10, M c. ligand c, with a percent occupancy of 30% at 1 M d. ligand D, with a percent occupancy of 80% at 10 nM 26. What is the nature of the mutated amino acid on hemoglobin that causes sickle cell disease? a. It is a mutation from an acidic to a basic residue that creates a new salt bridge and leads to hemoglobin fibril formati b. It is a mutation of histidine to alanine that disrupts heme binding, completely abolishing oxygen binding. c. It is a mutation from an acidic to a hydrophobic residue that creates a hydrophobic patch and leads to hemoglobin f formation through hydrophobic interactions. binding of oxygen. folding and becoming functional. d. It is a mutation from an acidic to a hydrophobic residue that disrupts tetramer formation and thus the cooperative e. It is a mutation from a hydrophobic to an acidic residue inside the protein core that prevents hemoglobin from prop

Explanation / Answer

1) Disulfide bonds are not positioned correctly unless weak bonding interactions are present - In presence of urea, the disulfide bonds are not positioned correctly and oxidation of protein results in covalent modification of protein. The covalent modification results in change of physical and chemical properties of protein. These changes that occur after oxidation, cannot be modified even if urea is removed. Hence, the protein cannot refold.

Related Questions

Navigate

• Browse (All)
• Browse 2
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.