Protein Folding Flashcards
What are the determinants of folding?
Secondary structure allows for efficient packing.
Folding is hierarchical.
Folding is context dependent.
Hydrophobic effect
What does the folding funnel explain?
At high entropy there’s high energy and little to no folding.
At low energy and entropy there’s a lot of folding, native states form.
What are the events of protein folding?
- Rapid formation of secondary structure
- Formation of domains through cooperative aggregation
- Formation of assembled domains (molten globule)
- Adjustment of conformation
What is the molten globule state?
Intermediate conformational state between native state and fully unfolded state of globular protein.
Name Characteristics of molten globule state
- Presence of native-like content of secondary structure
- The absence of a specific tertiary structure produced by the tight packing of AA.
- Not very compact compared to native state.
- Very loosely packed hydrophobic core.
Describe repeating motifs
When proteins have multiples of the similar units.
Ex: for cofactors to bind
Describe the alternative conformation of a peptide sequence.
Sequences can have different confirmations in different proteins
Ex: VDLLKN can be an alpha helix in one protein and beta in another protein.
What are metamorphic proteins?
When the protein has different conformations in different situations.
How can you predict secondary structure, given frequency?
Choose whichever frequency value is greater (alpha or beta). If those numbers are close choose depending on if the amino acid is hydrophobic or hydrophilic. Alpha helices are more hydrophobic and beta sheets are more hydrophilic.
What interactions dictate protein folding stability?
Non covalent- short range repulsion Electrostatic forces Van see waals Hydrogen bonding Hydrophobic interactions
