Soluble ER-resident proteins contain C-terminal KDEL sorting signal that allows them to be retrieved. 

TLS Online TPP Program

#Id: 8158

#XL - Q Biochemistry

Soluble ER-resident proteins contain C-terminal KDEL sorting signal that allows them to be retrieved. 

TLS Online TPP Program

#Id: 8755

#XL - T Zoology

Thermodynamic measurements indicate that native proteins are only marginally stable under physiological conditions. The free energy required to denature them is ∼0.4 kJ ∙ mol−1 per amino acid residue.

TLS Online TPP Program

#Id: 8756

#XL - T Zoology

Protein stability is the net balance of forces, which determine whether a protein will be in its native folded conformation or a denatured state.

TLS Online TPP Program

#Id: 8757

#XL - T Zoology

A fully folded 100-residue protein is only about 40 kJ ∙ mol−1 more stable than its unfolded form (for comparison, the energy required to break a typical hydrogen bond is ∼20 kJ ∙ mol−1).

TLS Online TPP Program

#Id: 8758

#XL - T Zoology

The combined hydrophobic and hydrophilic tendencies of individual amino acid residues in proteins can be expressed as hydropathies. The greater a side chain’s hydropathy, the more likely it is to occupy the interior of a protein.

TLS Online TPP Program

#Id: 8759

#XL - T Zoology

Hydrogen bonds, which are central features of protein structures, make only minor contributions to protein stability.

TLS Online TPP Program

#Id: 8760

#XL - T Zoology

This is because hydrogen-bonding groups in an unfolded protein form hydrogen bonds with water molecules. Thus the contribution of a hydrogen bond to the stability of a native protein is the small difference in hydrogen bonding free energies between the native and unfolded states (−2 to 8 kJ ∙ mol−1)