Contacts of the helix formed by residues 20 - 42 (chain A) in PDB entry 3LKB


Residue contacts within the protein are derived with the CSU software (Sobolev V., Sorokine A., Prilusky J., Abola E.E. and Edelman M. (1999) Automated analysis of interatomic contacts in proteins. Bioinformatics, 15, 327-332). A short description of the analytical approach is given at the end of the page.
For CSU analysis of other PDB entry

Note:
Non-standard 3 letter residue codes indicate a heterogroup. To identify and analyse, use LPC software

Legend:
Dist - nearest distance (Å) between atoms of two residues
Surf - contact surface area (Å2) between two residues
HB   - hydrophilic-hydrophilic contact (hydrogen bond)
Arom - aromatic-aromatic contact
Phob - hydrophobic-hydrophobic contact
DC   - hydrophobic-hydrophilic contact (destabilizing contact)
+/-  - indicates presence/absence of a specific contacts
*    - indicates residues forming contacts  by their side chain
       (including CA atoms)
Residues in contact with THR 20 (chain A).
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     15A  ALA*     4.3     0.2    -      -       +      -
     19A  PRO*     1.3    74.7    -      -       -      +
     21A  SER*     1.3    58.7    +      -       -      +
     22A  ASP      3.2     3.1    -      -       -      -
     23A  ALA*     3.0    21.3    +      -       -      +
     58A  TYR*     3.8    16.8    +      -       +      -
     82A  TYR*     2.4    51.6    +      -       +      +
    151A  HIS*     4.2     9.2    +      -       -      -
    155A  PHE*     4.1    11.3    -      -       -      -
    207A  VAL*     3.8    12.8    -      -       +      +
    393A  VAL      3.6    20.5    +      -       -      +
   4571A  IPA      3.2    20.1    -      -       -      +
----------------------------------------------------------
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Residues in contact with SER 21 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     15A  ALA      3.5    21.3    -      -       -      -
     16A  ILE      3.5    16.2    -      -       -      -
     17A  THR*     3.6     8.2    -      -       -      -
     18A  GLY      2.8    23.9    +      -       -      -
     19A  PRO      3.2     0.8    +      -       -      -
     20A  THR*     1.3    73.7    -      -       -      +
     22A  ASP*     1.3    67.4    +      -       -      +
     23A  ALA      2.9     2.8    +      -       -      -
     24A  GLY      3.7     0.2    -      -       -      -
     25A  ALA*     3.0    24.8    +      -       -      +
   4571A  IPA      3.5    11.6    +      -       -      +
----------------------------------------------------------
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Residues in contact with ASP 22 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     20A  THR      3.1     0.6    +      -       -      -
     21A  SER*     1.3    77.2    +      -       -      +
     23A  ALA*     1.3    57.3    +      -       +      +
     26A  PRO*     3.3    18.9    -      -       -      +
    207A  VAL*     4.0    13.1    -      -       +      +
    208A  ALA*     4.6     8.1    -      -       +      +
    209A  GLY*     3.1    31.3    +      -       -      -
    237A  ASP*     4.5    13.7    -      -       +      +
    241A  LEU*     4.5    14.4    -      -       +      +
    286A  ASN*     4.7     1.4    +      -       -      -
   4571A  IPA      2.8    33.0    +      -       -      +
----------------------------------------------------------
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Residues in contact with ALA 23 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     20A  THR*     3.0     8.3    +      -       +      +
     21A  SER      3.0     0.2    -      -       -      -
     22A  ASP*     1.3    79.5    -      -       +      +
     24A  GLY*     1.3    65.6    +      -       -      +
     25A  ALA      3.3     2.1    +      -       -      -
     26A  PRO*     3.3     3.9    -      -       -      +
     27A  TYR*     3.1    25.1    +      -       -      +
     82A  TYR*     3.9     5.6    -      -       +      +
    207A  VAL*     4.0    11.9    -      -       +      -
    232A  TYR*     3.5    36.6    -      -       +      +
    286A  ASN*     3.6    16.7    -      -       -      +
    393A  VAL      5.5     0.4    -      -       -      +
----------------------------------------------------------
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Residues in contact with GLY 24 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     12A  TRP*     3.6     8.7    -      -       -      -
     15A  ALA      3.2    20.2    -      -       -      -
     16A  ILE*     4.3     1.0    -      -       -      -
     20A  THR      3.2     3.2    +      -       -      -
     21A  SER      3.4     0.4    +      -       -      -
     23A  ALA*     1.3    78.8    -      -       -      +
     25A  ALA*     1.3    55.7    +      -       -      +
     27A  TYR*     4.1     1.6    -      -       -      -
     28A  GLY*     2.8    27.5    +      -       -      -
     82A  TYR*     3.0    32.2    +      -       -      -
----------------------------------------------------------
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Residues in contact with ALA 25 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     15A  ALA      3.6     2.4    +      -       -      -
     16A  ILE*     3.7    27.4    -      -       -      +
     21A  SER*     3.0    15.5    +      -       -      +
     24A  GLY*     1.3    75.8    -      -       -      +
     26A  PRO*     1.3    65.5    -      -       +      +
     28A  GLY*     3.2     0.7    +      -       -      -
     29A  ALA*     2.9    29.5    +      -       -      +
    281A  PHE*     3.7    11.6    -      -       +      -
     17B  THR*     3.8    20.4    -      -       +      -
----------------------------------------------------------
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Residues in contact with PRO 26 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     22A  ASP      3.3    24.9    -      -       -      +
     23A  ALA      3.3    10.3    -      -       -      +
     25A  ALA*     1.3    96.1    -      -       +      +
     27A  TYR*     1.3    54.4    +      -       -      +
     29A  ALA*     3.2     0.3    +      -       -      +
     30A  ALA*     2.9    25.6    +      -       -      +
    237A  ASP*     4.9     1.3    -      -       -      +
    281A  PHE*     3.6    29.2    -      -       +      -
    284A  SER*     3.9    23.6    -      -       -      +
    286A  ASN*     4.0     7.2    -      -       +      -
    287A  TYR*     3.4    27.0    -      -       +      +
----------------------------------------------------------
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Residues in contact with TYR 27 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     12A  TRP*     3.1    40.4    -      +       -      -
     23A  ALA      3.1    20.7    +      -       -      +
     24A  GLY*     3.7     7.6    -      -       -      +
     26A  PRO*     1.3    74.9    -      -       -      +
     28A  GLY*     1.3    66.0    +      -       -      +
     30A  ALA*     3.2     4.3    +      -       -      +
     31A  VAL*     3.2    23.7    +      -       +      +
     80A  LEU*     5.8     0.8    -      -       +      +
     81A  SER      4.3     1.2    +      -       -      -
     82A  TYR*     4.9     2.5    -      +       -      -
    102A  ILE      4.7     1.0    +      -       -      -
    103A  PRO      4.0     2.8    +      -       -      -
    104A  ALA*     3.3    41.6    +      -       +      +
    122A  PRO*     5.4     0.7    -      -       -      +
    232A  TYR*     4.5     2.7    -      +       -      -
    286A  ASN*     3.4    15.1    +      -       +      +
    289A  ASN*     3.5    34.5    +      -       +      -
    290A  GLY*     3.5    25.1    -      -       -      -
    293A  ALA*     3.3    22.1    -      -       +      +
----------------------------------------------------------
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Residues in contact with GLY 28 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     12A  TRP*     3.8    31.0    -      -       -      -
     16A  ILE*     4.8     3.1    -      -       -      -
     24A  GLY      2.8    20.6    +      -       -      -
     25A  ALA      3.8     0.9    -      -       -      -
     27A  TYR*     1.3    73.4    -      -       -      +
     29A  ALA*     1.3    63.2    +      -       -      +
     31A  VAL*     3.1    14.2    +      -       -      +
     32A  GLU*     3.1    13.4    +      -       -      +
     53A  VAL*     4.2     9.7    -      -       -      +
----------------------------------------------------------
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Residues in contact with ALA 29 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     16A  ILE*     5.8     0.2    -      -       -      +
     25A  ALA      2.9    17.1    +      -       -      +
     26A  PRO      3.5     5.4    -      -       -      +
     28A  GLY*     1.3    77.2    -      -       -      +
     30A  ALA*     1.3    56.4    +      -       -      +
     32A  GLU*     3.3     2.8    +      -       -      -
     33A  ASP*     2.9    33.3    +      -       -      -
    277A  ARG*     3.4    34.9    +      -       -      +
    281A  PHE*     3.9    18.6    -      -       +      -
    287A  TYR*     3.9     4.9    -      -       +      -
     57B  GLN*     5.3     0.2    -      -       -      +
----------------------------------------------------------
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Residues in contact with ALA 30 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     26A  PRO      2.9    11.1    +      -       -      +
     27A  TYR      3.2     4.2    +      -       -      +
     29A  ALA*     1.3    77.1    -      -       -      +
     31A  VAL*     1.3    62.6    +      -       -      +
     33A  ASP*     3.8     0.8    -      -       -      +
     34A  TYR*     2.9    27.4    +      -       -      +
    287A  TYR*     3.1    51.5    -      -       +      +
    290A  GLY*     3.8     2.2    -      -       -      -
    291A  MET*     3.5    19.0    -      -       +      +
----------------------------------------------------------
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Residues in contact with VAL 31 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     10A  LEU*     5.1     9.4    -      -       +      +
     12A  TRP*     4.1    25.4    -      -       +      +
     27A  TYR*     3.2    31.5    +      -       +      +
     28A  GLY      3.1     7.9    +      -       -      +
     30A  ALA*     1.3    76.4    -      -       -      +
     32A  GLU*     1.3    62.9    +      -       -      +
     34A  TYR*     3.9     1.2    -      -       -      +
     35A  CYS*     3.0    23.7    +      -       -      +
     51A  CYS*     5.2     2.7    -      -       -      -
     53A  VAL*     4.4     8.1    -      -       +      -
     80A  LEU*     3.8    27.6    -      -       +      -
    290A  GLY      3.9    14.8    -      -       -      +
    293A  ALA*     5.4     0.4    -      -       +      -
    294A  ALA*     4.0    11.4    -      -       +      +
----------------------------------------------------------
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Residues in contact with GLU 32 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     28A  GLY      3.1     8.9    +      -       -      +
     29A  ALA*     3.7     7.6    -      -       -      +
     31A  VAL*     1.3    79.7    -      -       -      +
     33A  ASP*     1.3    62.3    +      -       -      +
     35A  CYS*     3.4     2.8    +      -       -      +
     36A  LYS*     3.0    54.2    +      -       -      +
     51A  CYS*     3.6    21.9    -      -       -      -
     53A  VAL*     4.0    24.1    -      -       +      +
    277A  ARG*     4.4    11.3    +      -       -      +
     54B  ARG*     4.7     9.7    +      -       -      -
     66B  PHE*     6.2     0.3    -      -       -      -
----------------------------------------------------------
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Residues in contact with ASP 33 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     29A  ALA      2.9    17.9    +      -       -      +
     30A  ALA*     3.8     2.9    -      -       -      +
     32A  GLU*     1.3    76.8    -      -       -      +
     34A  TYR*     1.3    61.1    +      -       -      +
     36A  LYS*     3.1    11.8    -      -       -      +
     37A  TRP*     2.8    25.5    +      -       -      +
    271A  ILE*     3.7    13.0    -      -       +      +
    275A  TYR*     3.5    25.9    -      -       +      +
    277A  ARG*     2.7    41.3    +      -       -      +
    287A  TYR*     2.7    28.7    +      -       +      +
    291A  MET*     5.1     0.2    -      -       +      -
----------------------------------------------------------
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Residues in contact with TYR 34 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     30A  ALA      2.9    18.0    +      -       -      +
     31A  VAL      3.9     2.5    -      -       -      +
     33A  ASP*     1.3    76.6    -      -       -      +
     35A  CYS*     1.3    52.6    +      -       -      +
     37A  TRP*     3.1    14.2    +      +       -      +
     38A  ALA*     2.7    32.1    +      -       -      +
     43A  LEU*     3.8    20.8    -      -       +      +
    267A  LEU*     4.1    23.5    -      -       +      +
    271A  ILE*     4.0    12.7    -      -       +      +
    291A  MET*     3.6    27.3    -      -       +      +
    294A  ALA*     3.8    15.3    -      -       +      -
    295A  ALA*     3.5    41.7    +      -       +      +
    298A  VAL*     4.0    24.9    -      -       +      +
    329A  PHE*     5.4     2.9    -      -       -      -
    333A  PHE*     5.2     1.6    -      +       -      -
----------------------------------------------------------
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Residues in contact with CYS 35 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     10A  LEU*     3.7    32.1    -      -       +      -
     31A  VAL*     3.0    18.6    +      -       +      +
     32A  GLU      3.7     3.6    -      -       -      +
     34A  TYR*     1.3    78.8    -      -       -      +
     36A  LYS*     1.3    61.9    +      -       -      +
     38A  ALA*     3.4     8.8    +      -       -      +
     39A  ASN*     3.3    23.7    +      -       -      -
     49A  PHE*     3.2    35.4    -      -       -      -
     51A  CYS*     3.7    29.6    -      -       +      -
    294A  ALA*     5.2     0.4    -      -       -      +
    298A  VAL*     5.3     0.2    -      -       -      -
----------------------------------------------------------
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Residues in contact with LYS 36 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     32A  GLU*     3.0    45.2    +      -       +      +
     33A  ASP*     3.1    13.7    -      -       -      +
     35A  CYS*     1.3    78.6    -      -       -      +
     37A  TRP*     1.4    60.7    +      -       -      +
     39A  ASN*     3.3    11.5    +      -       -      +
     40A  GLU*     3.0    32.0    +      -       -      +
     51A  CYS*     5.3     9.6    -      -       -      +
    275A  TYR*     3.4    33.0    -      -       +      +
     54B  ARG*     4.4    15.4    -      -       -      +
     65B  ARG*     6.0     3.8    -      -       -      +
----------------------------------------------------------
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Residues in contact with TRP 37 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     33A  ASP      2.8    12.9    +      -       -      +
     34A  TYR*     3.5    16.4    -      +       -      +
     36A  LYS*     1.4    74.3    -      -       -      +
     38A  ALA*     1.3    65.0    +      -       -      +
     40A  GLU*     3.3     2.6    +      -       +      -
     41A  ARG*     3.0    66.6    +      -       +      +
     43A  LEU*     3.5    41.5    -      -       +      -
    267A  LEU*     3.5    38.7    -      -       +      +
    270A  GLU*     4.6    13.6    +      -       +      +
    271A  ILE*     3.5    36.4    -      -       +      +
    274A  LYS*     5.0    15.1    -      -       +      +
    275A  TYR*     3.2    14.5    +      +       +      +
----------------------------------------------------------
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Residues in contact with ALA 38 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     34A  TYR*     2.7    17.2    +      -       +      +
     35A  CYS*     3.5    13.9    -      -       -      +
     36A  LYS      3.4     0.2    -      -       -      -
     37A  TRP*     1.3    72.1    -      -       -      +
     39A  ASN*     1.3    58.6    +      -       -      +
     42A  LYS*     3.0    24.9    +      -       -      -
     43A  LEU*     3.1    33.4    +      -       +      -
     44A  VAL      4.8     0.7    +      -       -      -
     49A  PHE*     3.9    27.0    -      -       +      -
    298A  VAL*     4.3    11.0    -      -       +      -
----------------------------------------------------------
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Residues in contact with ASN 39 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     35A  CYS*     3.3    14.5    +      -       -      -
     36A  LYS*     3.3    11.2    +      -       -      +
     37A  TRP      3.2     1.0    -      -       -      -
     38A  ALA*     1.3    79.0    -      -       -      +
     40A  GLU*     1.3    63.2    +      -       +      +
     42A  LYS*     3.4    22.1    +      -       -      +
     47A  VAL      4.0     3.6    -      -       -      +
     48A  VAL*     3.5    13.6    -      -       -      +
     49A  PHE*     2.7    53.9    +      -       -      +
     51A  CYS*     6.1     0.2    -      -       -      +
----------------------------------------------------------
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Residues in contact with GLU 40 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     36A  LYS*     3.0    23.3    +      -       -      +
     37A  TRP*     3.9     4.3    -      -       +      +
     39A  ASN*     1.3    76.8    -      -       +      +
     41A  ARG*     1.3    73.8    +      -       +      +
     42A  LYS*     3.7     8.3    +      -       -      +
    274A  LYS*     3.6    26.6    +      -       -      -
    275A  TYR*     3.2    29.9    +      -       -      +
----------------------------------------------------------
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Residues in contact with ARG 41 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     37A  TRP*     3.0    58.0    +      -       +      +
     40A  GLU*     1.3    85.2    +      -       +      +
     42A  LYS*     1.3    71.8    +      -       -      +
     43A  LEU*     3.2    22.0    +      -       +      +
    270A  GLU*     6.0     0.4    -      -       -      -
    274A  LYS*     6.3     1.8    -      -       -      +
----------------------------------------------------------
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Residues in contact with LYS 42 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     38A  ALA      3.0     9.9    +      -       -      -
     39A  ASN*     3.4    14.3    +      -       -      +
     40A  GLU      3.4     9.1    +      -       -      +
     41A  ARG*     1.3    80.9    -      -       -      +
     43A  LEU*     1.3    65.6    +      -       -      +
     44A  VAL*     3.2    14.2    +      -       -      +
     45A  PRO*     4.1    11.7    -      -       +      +
     46A  GLY      6.1     0.9    -      -       -      +
     47A  VAL      5.9     3.6    -      -       -      +
----------------------------------------------------------
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A short description of the analytical approach
The contact analysis used in this page is based upon the approach developed in: Sobolev V., Wade R.C., Vriend G. and Edelman M. PROTEINS (1996) 25, 120-129. Contact legitimacy depends on the hydrophobic-hydrophilic properties of the contacting atoms. In order to define it, for each inter-atomic contact, eight atom classes have been introduced:


   I  Hydrophilic      - N and O that can donate and accept hydrogen bonds
                         (e.g., oxygen of hydroxyl group of Ser. or Thr)
  II  Acceptor         - N or O that can only accept a hydrogen bond
 III  Donor            - N that can only donate a hydrogen bond
  IV  Hydrophobic      - Cl, Br, I and all C atoms that are not in
                         aromatic rings and do not have a covalent bond to
                         a N or O atom
   V  Aromatic         - C in aromatic rings irrespective of any other 
                         bonds formed by the atom
  VI  Neutral          - C atoms that have a covalent bond to at least one
                         atom of class I or two or more atoms from class II
                         or III; atoms; S, F, P, and metal atoms in all cases
 VII  Neutral-donor    - C atoms that have a covalent bond with only one
                         atom of class III
VIII  Neutral-acceptor - C atoms that have a covalent bond with only 
                         one atom of class II
For each pair of contacts the state of legitimacy is shown below:

Legend:
+, legitimate
-, illegitimate
------------------------------------------------------------
  Atomic class           I  II  III   IV   V   VI  VII  VIII
------------------------------------------------------------
   I  (Hydrophilic)      +   +    +    -   +   +    +    +
  II  (Acceptor)         +   -    +    -   +   +    +    -
 III  (Donor)            +   +    -    -   +   +    -    +
  IV  (Hydrophobic)      -   -    -    +   +   +    +    +
   V  (Aromatic)         +   +    +    +   +   +    +    +
  VI  (Neutral)          +   +    +    +   +   +    +    +
 VII  (Neutral-donor)    +   +    -    +   +   +    -    +
VIII  (Neutral-acceptor) +   -    +    +   +   +    +    -
------------------------------------------------------------
Warning!
Atom classes for heterogroups are automatically assigned based on the atomic coordinates. However, in three cases (see below) the automatic assignment is currently ambiguous. In these cases, the user is advised to manually analyse the full list of contacts using LPC software.
1. Carbon atoms belonging to a 4-, 5- or 6-member ring are 
   considered "aromatic" (Class V) if the ring is approximately
   planar, and "hydrophobic" (Class IV) or "neutral" (Classes
   VI, VII, VIII) if the ring is non-planar.
2. The oxygen atom of a carbonyl or hydroxy group is considered
   "hydroxy" (Class I) if the CO bond is longer than 1.29 Å, and
   "carbonyl" (Class II) if shorter.
3. All nitrogen atoms are considered "hydrophilic" (Class I).

Please E-mail any questions and/or suggestions concerning this page to Vladimir.Sobolev@weizmann.ac.il