Which statement is true about protein folding? ○ The equilibrium between folded and unfolded states is best determined by measuring the time course of unfolding ○ Refolding of a protein typically exhibits a linear dependence on the concentration of denaturant ○ The sigmoidal shape of the unfolding transition reflects the complex architecture of proteins ○ Proteins with stable folding intermediates usually exhibit smooth free-energy funnels ○ The rate of unfolding increases as the temperature increases towards the Tm value

Which statement is true about protein folding? ○ The equilibrium between folded and unfolded states is best determined by measuring the time course of unfolding ○ Refolding of a protein typically exhibits a linear dependence on the concentration of denaturant ○ The sigmoidal shape of the unfolding transition reflects the complex architecture of proteins ○ Proteins with stable folding intermediates usually exhibit smooth free-energy funnels ○ The rate of unfolding increases as the temperature increases towards the Tm value

Biochemistry

6th Edition

ISBN:9781305577206

Author:Reginald H. Garrett, Charles M. Grisham

Publisher:Reginald H. Garrett, Charles M. Grisham

Chapter31: Completing The Protein Life Cycle: Folding, Processing, And Degradation

Section: Chapter Questions

Problem 3P: Understanding the Relevance of Chaperones in Protein Folding Protein molecules, like all molecules,...

See similar textbooks

Similar questions

Which of the following statements are correct about protein folding (select all that appy)? A. Protein folding is a very slow process with most proteins requiring >30 min to go from unfolded to native conformation B. The mature two-chain form of insulin spontaneously folds into the native conformation C. A sharp transition in the presence of denaturants (See Figue 8.1) suggests the protein folds without intermediates D. Proteins randomly sample each possible conformation before arriving final native state E. Proteins with disulfide bridges tend not follow a simple two-state folding mechanism.
Which of the following statements best describe(s) the mechanism by which correct protein folding takes place once the misfolded protein binds the open ring of groEL? Select all that apply. The groEL ring closes to isolate the protein and provide enough time for the protein to properly fold on its own. b and d The groEL ring closes to provide a hydrophilic space to isolate the protein and inhibit its aggregation with others until properly folded. The groEL ring closes to isolate the protein and provide steric hindrance that mechanically refolds the protein. The groEL ring closes to isolate the protein and decode the information necessary to achieve the correct three-dimensional structure. None of the above I picked "The groEL ring closes to provide a hydrophilic space..." but it was incorrect..
Proper folding of proteins is essential for their biological activity. In general, the functional conformation of a protein is the conformation with lowest energy. This means that if an unfolded protein is allowed to reach equilibrium, it should assemble automatically into its native, functioning folded state. Why then is there a need for molecular chap- erones and chaperonins in cells? What different roles do molecular chaperones and chaperonins play in the folding of proteins?
Proper folding of proteins is essential for their biological activity. In general, the functional conformation of a protein is the conformation with lowest energy. This means that if an unfolded protein is allowed to reach equilibrium, it should assemble automatically into its native, functioningfolded state. Why then is there a need for molecular chaperones and chaperonins in cells? What different roles do molecular chaperones and chaperonins play in the folding of proteins?
The process of a protein folding from an inactive unfolded structure to theactive folded structure can be represented by the following equation: unfolded protein ⇌ folded proteinThe values of ΔH° and ΔS° for the folding of the protein lysozyme are: ΔH ° = -280 kJ/ mol ΔS ° = -790 J/mol • K(a) Calculate the value of ΔG° for the folding of lysozyme at 25 °C.(b) At what temperature would you expect the unfolding of lysozyme tobecome favorable? (c) At what temperature would the ratio of unfolded protein to foldedprotein be 1:5?
a) Canonical forces in protein folding. Describe how these forces come into play when a protein folds. Why do are other intermolecular interactions important to fully understand folding processes?
Which of the following statements are correct about the molten globular state of protein folding (select all that appy)? A. May be short-lived or long-lived intermediate in protein folding B. Contains substantial levels of secondary structure C. Has loose packing of hydrophobic core D. Larger radius of gyration than dentaured state E. Is a more compact state than the native confomation
The major difference between a protein molecule in its native state and inits denatured state lies in the number of conformations available. To a firstapproximation, the native, folded state can be thought to have one conformation. The unfolded state can be estimated to have three possible orientations about each bond between residues.(a) For a protein of 100 residues, estimate the entropy change per moleupon denaturation.(b) What must be the enthalpy change accompanying denaturation to allow the protein to be half-denatured at 50 °C?(c) Will the fraction denatured increase or decrease with increasingtemperature?
An intermediate folding stage seen in protein denaturation or renaturation is called : a) domain b) motif c) subunit d) molten globule Proteins which do not renature spontaneously when denaturation conditions are removed may need the assistance of: a) a prosthetic group b) a higher salt concentration c) a lower temperature d) a chaperone protein The information needed for correct protein folding is encoded in: a) the surrounding molecules b) the protein’s amino acid sequence c) the pH of the aqueous medium d) the electrolyte composition of the aqueous solution
Which of the following statements are correct about the role of chaperones in protein folding (select all that appy)? A. Chaperones accelerate the rate of protein folding B. Presence of chaperones contradicts dogma that structure of protein is only determined by amino acid sequence C. Chapreone promotion of native folding is an ATP-dependent process D. Chaperones work by stabilizing hydrophobic patches on proteins E. A cell line with the GroEL and GroES deleted would accumulate more unfolded protein
Which intermolecular forces are important in acetic acid, CH3 –(C=0)-oh? A particular amino acid contains a- CHNH3+ group. Is this amino acid more likely to be found on the inside or the outside of the folded protein? Briefly explain. The addition of ethanol, CH3CHOH, t an aqueous solution lowers the surface tension of the solution. Predict whether adding ethanol to an aqueous protein solution will tend to stabilize or unfold the protein. Briefly explain.
Peptides and small proteins fold spontaneously in aqueous solution at room temperature. Thus, for a small protein in water, we can say ΔG FOLD < 0. Denoting the unfolded protein as Unf and the folded protein as Fld, we can write the following equation:Unf(aq)--DELTA G FOLD----> Fld(aq)Considering the transition from the unfolded state (in which there are many possible conformations) to the folded state (only one conformation), there is clearly a decrease in the entropy of the protein. However, protein folding is (correctly) described as an entropically driven process.a) Resolve this apparent paradox by identifying the enthalpy (ΔH) and entropy (−TΔS)components involved in protein…