TABLE 3.

Comparison of the experimental and computational results for membrane-associated helices and membrane proteins of known conformation

Experimental and computed peptide orientations
		Experiment		Calculated
PDB	Name	Helix residues	Tilt angle (°)	Tilt angle (°)	z (Å)	ΔE (kcal/mol)
1a11	Acetylcholine M2 (1cek)	2–24	11	11 ± 5	−1.0 ± 0.9	−5.0 ± 0.9
1mp6	Influenza A M2	23–45	37	25	−1.1	−12.8
1mzt	FD coat protein	21–44	19	15	−1.5	−0.83
2mag	Magainin	4–21	∼90	85 ± 4	17.6 ± 0.9	−4.6 ± 0.8
1hu5	Ovispirin 1	4–16	∼90	89 ± 12	18.1 ± 0.6	−3.3 ± 0.4
1f0d	Magainin-cecropin hybrid	11–17	∼90	89 ± 27	21.3 ± 2.0	−2.3 ± 0.6

The residues defining the helical segment, as well as the experimental tilt angle, are listed. The helix tilt angle, displacement of the center of mass of the helix with respect to the membrane center (z), and insertion energy (ΔE) are listed for all systems. The experimental tilt angles were calculated from the aligned solid-state NMR structures deposited in the Protein Databank.