Solvent accessibility classes were defined in quantiles, i.e. each class has the same number of amino acids.
 Upper limits (in % of solvent exposure relative to the Ala-X-Ala tripeptide) of the solvent accessibility classes used in the study, for each D:
  
 2 classes: 21.3; 199.3; 
 4 classes: 3.5; 21.3; 48.1; 199.3; 
 6 classes: 0.9; 7.8; 21.3; 38.6; 58.5; 199.3; 
 8 classes: 0.3; 3.5; 10.6; 21.3; 34.1; 48.1; 64.8; 199.3; 
10 classes: 0.2; 1.7; 5.9; 12.6; 21.3; 31.4; 42.3; 54.1; 69.3; 199.3; 
12 classes: 0.1; 0.9; 3.5; 7.8; 13.9; 21.3; 29.7; 38.6; 48.1; 58.5; 72.7; 199.3; 
14 classes: 0.1; 0.6; 2.2; 5.1; 9.4; 14.9; 21.3; 28.4; 36; 43.9; 52.3; 61.9; 75.4; 199.3; 
16 classes: 0.1; 0.3; 1.4; 3.5; 6.6; 10.6; 15.6; 21.3; 27.5; 34.1; 41; 48.1; 55.7; 64.8; 77.5; 199.3; 
18 classes: 0.1; 0.2; 0.9; 2.5; 4.8; 7.8; 11.7; 16.3; 21.3; 26.8; 32.6; 38.6; 44.8; 51.4; 58.5; 67.2; 79.2; 199.3; 
20 classes: 0.1; 0.2; 0.7; 1.7; 3.5; 5.9; 8.9; 12.6; 16.7; 21.3; 26.2; 31.4; 36.8; 42.3; 48.1; 54.1; 60.8; 69.3; 80.8; 199.3;