Section 2

Membrane Protein Stability and Biophysical Methods

Membrane proteins have a fundamentally different energetic problem to solve in order to fold. It can be referred to as a Janus complex. This is because they must satisfy both the energetic requirements of the hydrophobic membrane and the hydrophilic requirements of the aqueous cytoplasm. Because of the overriding energetics of the hydrophobic membrane, early notions of membrane proteins envisioned that they would be "inside out" compared to soluble proteins. That is, they would have a hydrophilic core and a hydrophobic exterior.

Jan 22 Reading: Structure and Stability of membrane proteins

Query 3   What is a hydropathy plot and what can and cannot  it predict about membrane protein structure?

Query 4   How do the membrane lipids contribute to membrane protein stability?

Jan 24 Reading: Biophysical Methods

Query 3b     What is the "phase problem"?

Query 4b   List an advantage and disadvantage for both X-ray and NMR structure determination of membrane proteins?