An Integrated Framework Advancing Membrane Protein Modeling and Design
Fig 4
MPddG computes free energy changes upon mutation in the membrane environment (ΔΔG).
(A) Outer membrane protein phospholipase A (OmpLA, PDB 1qd6) with its native alanine at position 210 in red at the center of the membrane. (B) Plot of RosettaMP-calculated fixed-backbone ΔΔGs versus experimentally measured values of Moon & Fleming for variants at position 210 [50]. Proline is off-scale (ΔΔGpred = 193.2 REU) due to incompatible backbone torsions yielding ring closure penalties. (C) Outer membrane protein A (OmpA, PDB 1qjp) with aromatic residues mutated to alanine at various interfacial positions. (D) Plot of RosettaMP-calculated ΔΔGs versus experimentally measured values of Hong & Tamm [51]. The mutation W15A is off-scale (ΔΔGpred = -43.0 REU) due to the loss of repulsive interactions upon mutation to alanine. Both (B) and (D) include a line for y = x.