Contacts of the helix formed by residues 23 - 47 (chain A) in PDB entry 2Q06


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 23 (chain A).
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     22A  ALA*     1.3    75.7    -      -       -      +
     24A  GLU*     1.3    60.4    +      -       -      +
     25A  ILE      3.2     0.7    -      -       -      +
     26A  ARG*     3.6    26.9    -      -       +      -
     27A  ALA*     2.9    29.0    +      -       +      +
----------------------------------------------------------
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Residues in contact with GLU 24 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     22A  ALA*     3.6    19.4    +      -       +      +
     23A  THR*     1.3    76.2    -      -       -      +
     25A  ILE*     1.3    79.1    +      -       -      +
     26A  ARG      3.0     1.5    +      -       -      -
     27A  ALA*     3.2     5.4    +      -       -      +
     28A  SER*     2.7    38.8    +      -       -      +
----------------------------------------------------------
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Residues in contact with ILE 25 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     22A  ALA      3.4    24.7    +      -       -      +
     23A  THR      3.2     0.4    -      -       -      -
     24A  GLU*     1.3    97.8    +      -       -      +
     26A  ARG*     1.3    64.1    +      -       +      +
     28A  SER*     3.5    10.2    +      -       -      -
     29A  VAL*     3.2    27.6    -      -       +      +
----------------------------------------------------------
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Residues in contact with ARG 26 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     23A  THR*     3.2    28.4    +      -       +      +
     24A  GLU      3.0     0.6    -      -       -      -
     25A  ILE*     1.3    81.9    -      -       +      +
     27A  ALA*     1.3    61.1    +      -       -      +
     28A  SER      3.2     1.8    -      -       -      -
     29A  VAL      3.8     0.9    -      -       -      -
     30A  GLY      3.3     9.7    +      -       -      -
    294A  GLU      2.5    32.1    +      -       -      -
    295A  GLY*     3.0    17.2    +      -       -      -
    296A  TYR      3.0    45.7    +      -       -      +
    297A  SER*     4.4     9.0    -      -       -      +
    301A  ILE*     5.1     3.0    -      -       -      +
    302A  ASP*     2.3    38.0    +      -       -      -
    305A  ARG*     4.5     6.1    -      -       -      +
----------------------------------------------------------
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Residues in contact with ALA 27 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     23A  THR*     2.9    19.7    +      -       +      +
     24A  GLU*     4.0     4.7    -      -       -      +
     26A  ARG*     1.3    77.1    -      -       -      +
     28A  SER*     1.3    59.1    +      -       -      +
     29A  VAL      3.4     0.2    -      -       -      -
     30A  GLY      4.1     0.6    -      -       -      -
     31A  ARG*     3.2    22.2    +      -       -      +
    292A  GLU*     4.3    24.1    -      -       +      +
    295A  GLY*     4.5     9.0    -      -       -      -
----------------------------------------------------------
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Residues in contact with SER 28 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     24A  GLU*     2.7    28.6    +      -       -      +
     25A  ILE*     3.5    10.0    +      -       -      -
     27A  ALA*     1.3    75.8    -      -       -      +
     29A  VAL*     1.3    65.7    +      -       -      +
     31A  ARG*     3.5    21.5    -      -       -      +
     32A  MET*     3.6    11.1    +      -       -      +
----------------------------------------------------------
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Residues in contact with VAL 29 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     25A  ILE*     3.2    21.7    +      -       +      +
     26A  ARG      3.6     1.0    +      -       -      +
     27A  ALA      3.4     0.2    -      -       -      -
     28A  SER*     1.3    78.8    +      -       -      +
     30A  GLY*     1.3    59.5    +      -       -      +
     32A  MET*     3.1    18.6    -      -       +      +
     33A  VAL*     3.0    23.6    +      -       -      +
    296A  TYR*     3.2    38.8    -      -       +      +
    297A  SER*     5.4     0.7    -      -       -      -
    298A  LEU*     3.8    37.2    -      -       +      -
----------------------------------------------------------
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Residues in contact with GLY 30 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     26A  ARG      3.3     9.4    +      -       -      -
     27A  ALA      4.0     1.1    +      -       -      -
     29A  VAL*     1.3    76.9    -      -       -      +
     31A  ARG*     1.3    58.2    +      -       -      +
     33A  VAL*     4.2     3.1    -      -       -      -
     34A  GLY*     2.7    32.6    +      -       -      -
    291A  PHE*     3.6    23.7    -      -       -      +
    296A  TYR*     3.7    22.2    -      -       -      -
    368B  ASN*     3.9     1.4    -      -       -      +
----------------------------------------------------------
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Residues in contact with ARG 31 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     27A  ALA      3.2    20.6    +      -       -      +
     28A  SER*     3.5    15.7    -      -       -      +
     30A  GLY*     1.3    76.1    -      -       -      +
     32A  MET*     1.3    59.8    +      -       -      +
     34A  GLY      3.5     0.2    +      -       -      -
     35A  GLY*     3.0    21.8    +      -       -      -
     38A  ARG*     3.6     7.6    +      -       -      -
    124A  ASN*     3.2    23.3    +      -       -      +
    125A  ASN*     4.5     6.9    +      -       -      +
    127A  GLU*     2.3    36.2    +      -       -      +
    129A  ALA*     3.9    25.3    -      -       -      +
    292A  GLU*     4.8     8.4    -      -       +      +
    368B  ASN*     3.9    23.8    +      -       -      +
----------------------------------------------------------
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Residues in contact with MET 32 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     28A  SER      3.6    10.5    +      -       -      +
     29A  VAL*     3.1    24.2    +      -       +      +
     30A  GLY      3.1     0.2    -      -       -      -
     31A  ARG*     1.3    80.9    -      -       +      +
     33A  VAL*     1.3    68.7    +      -       +      +
     35A  GLY*     3.4     8.1    +      -       -      +
     36A  ILE*     3.3    19.0    +      -       -      +
    120A  TRP*     5.4     0.5    -      -       -      -
    124A  ASN*     4.9     3.5    -      -       -      +
    129A  ALA*     5.1     7.0    -      -       +      +
    131A  ALA*     3.7    32.3    -      -       +      +
    132A  GLY*     3.8    18.6    -      -       -      +
    135A  HIS*     3.6    36.8    -      -       +      +
    298A  LEU*     4.9    13.0    -      -       +      -
----------------------------------------------------------
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Residues in contact with VAL 33 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     29A  VAL      3.0    17.0    +      -       -      +
     30A  GLY*     3.2     4.5    +      -       -      +
     32A  MET*     1.3    79.5    -      -       +      +
     34A  GLY*     1.3    70.3    +      -       -      +
     35A  GLY      2.9     1.1    -      -       -      -
     36A  ILE*     2.8    21.1    +      -       +      +
     37A  GLY*     3.1     9.7    +      -       -      -
    135A  HIS*     4.4    12.6    -      -       +      +
    281A  TYR*     3.7    40.2    -      -       +      +
    291A  PHE*     3.4    41.3    -      -       +      -
    296A  TYR*     4.3    15.3    -      -       +      -
    298A  LEU*     5.1     0.7    -      -       +      -
----------------------------------------------------------
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Residues in contact with GLY 34 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     30A  GLY      2.7    18.4    +      -       -      -
     33A  VAL*     1.3    74.2    -      -       -      +
     35A  GLY*     1.3    65.2    +      -       -      +
     37A  GLY      3.1     1.9    +      -       -      -
     38A  ARG*     3.0    44.7    +      -       -      -
    285A  VAL*     4.5     3.7    -      -       -      +
    291A  PHE*     4.0    21.3    -      -       -      -
----------------------------------------------------------
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Residues in contact with GLY 35 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     31A  ARG      3.0    12.3    +      -       -      -
     32A  MET      3.6     6.3    -      -       -      -
     33A  VAL      2.9     1.4    -      -       -      -
     34A  GLY*     1.3    79.1    -      -       -      +
     36A  ILE*     1.3    62.2    +      -       -      +
     38A  ARG*     3.2     9.5    +      -       -      +
     39A  PHE*     3.2    20.4    +      -       -      +
    120A  TRP*     4.6     1.3    -      -       -      -
    123A  ALA      4.2     3.5    -      -       -      +
    124A  ASN*     2.9    34.0    +      -       -      -
----------------------------------------------------------
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Residues in contact with ILE 36 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     32A  MET*     3.3    14.6    +      -       -      +
     33A  VAL*     2.8    21.5    +      -       +      +
     35A  GLY*     1.3    70.3    -      -       -      -
     37A  GLY*     1.3    57.3    +      -       -      +
     39A  PHE*     3.2     6.2    -      -       +      +
     40A  TYR*     2.9    28.6    +      -       +      +
    120A  TRP*     3.9    16.8    -      -       +      -
    132A  GLY*     3.9     9.2    -      -       -      +
    135A  HIS*     4.6    11.2    -      -       +      -
    136A  MET*     3.3    38.6    -      -       +      -
    278A  ALA*     3.8    34.5    -      -       +      +
    281A  TYR*     4.3    15.3    -      -       +      -
----------------------------------------------------------
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Residues in contact with GLY 37 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     33A  VAL      3.1     4.6    +      -       -      -
     34A  GLY      3.1     6.1    +      -       -      -
     36A  ILE*     1.3    76.5    -      -       -      +
     38A  ARG*     1.3    70.1    +      -       -      +
     40A  TYR*     3.3     2.1    +      -       -      +
     41A  ILE*     3.0    23.0    +      -       -      +
    281A  TYR*     3.5    30.7    -      -       -      +
    282A  GLY*     3.9     2.2    -      -       -      -
    285A  VAL*     3.6    12.3    -      -       -      -
----------------------------------------------------------
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Residues in contact with ARG 38 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     31A  ARG      3.6     3.6    +      -       -      -
     34A  GLY*     3.0    42.4    +      -       -      +
     35A  GLY*     3.2     6.3    -      -       -      +
     37A  GLY*     1.3    71.7    -      -       -      +
     39A  PHE*     1.3    66.2    +      -       -      +
     41A  ILE*     2.9     5.1    +      -       -      +
     42A  GLN*     2.8    24.6    +      -       -      +
    123A  ALA*     3.2    32.3    +      -       +      +
    124A  ASN*     4.7     1.4    -      -       -      +
    125A  ASN*     3.6     9.9    +      -       -      -
    285A  VAL*     4.0    20.6    -      -       +      +
    361B  ARG*     4.8    10.9    +      -       -      +
    366B  ALA*     6.4     0.7    -      -       -      -
    368B  ASN*     3.0    60.2    +      -       -      +
    369B  GLU*     4.5    24.2    -      -       +      +
    370B  ASN      5.0     2.0    -      -       -      +
----------------------------------------------------------
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Residues in contact with PHE 39 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     35A  GLY      3.2    11.3    +      -       -      +
     36A  ILE*     3.2    14.8    -      -       +      +
     38A  ARG*     1.3    76.6    -      -       -      +
     40A  TYR*     1.3    67.9    +      +       +      +
     42A  GLN*     3.0     6.6    +      -       -      +
     43A  MET*     2.7    56.1    +      -       +      +
     63A  ILE*     4.1    15.9    -      -       +      -
     64A  GLU*     6.0     0.2    -      -       -      -
     67A  VAL*     3.3    39.5    -      -       +      -
    116A  ILE*     4.1     7.2    -      -       +      -
    119A  ILE*     3.9    14.4    -      -       +      -
    120A  TRP*     3.5    60.3    -      +       +      -
    123A  ALA*     3.7    12.3    -      -       +      +
    136A  MET*     6.3     1.6    -      -       -      -
    278A  ALA*     6.2     1.8    -      -       +      -
----------------------------------------------------------
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Residues in contact with TYR 40 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     36A  ILE      2.9    14.7    +      -       -      +
     37A  GLY      3.6     3.6    -      -       -      +
     39A  PHE*     1.3    83.9    -      +       +      +
     41A  ILE*     1.3    65.2    +      -       +      +
     43A  MET*     3.1     6.0    +      -       -      +
     44A  CYS*     2.8    42.8    +      -       -      -
     49A  LEU*     5.4     0.9    -      -       -      +
     53A  GLU      4.9     0.2    +      -       -      -
     54A  GLY*     2.2    37.4    +      -       -      -
     56A  LEU      4.7     0.2    +      -       -      -
     59A  ASN*     5.0     0.7    -      -       -      +
     60A  SER*     3.5    25.3    +      -       -      -
     63A  ILE*     3.5    34.0    -      -       +      +
    278A  ALA*     3.8    27.6    -      -       +      +
    279A  CYS*     3.1    30.2    -      -       +      +
    282A  GLY*     3.7    13.9    -      -       -      -
    283A  LEU      5.2     1.3    -      -       -      -
----------------------------------------------------------
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Residues in contact with ILE 41 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     37A  GLY      3.0    12.5    +      -       -      +
     38A  ARG*     2.9     9.9    +      -       -      +
     40A  TYR*     1.3    78.1    -      -       +      +
     42A  GLN*     1.3    69.6    +      -       -      +
     44A  CYS*     2.8    24.0    +      -       +      +
     45A  THR*     3.6     9.1    +      -       +      +
    282A  GLY*     3.2    29.6    -      -       -      +
    285A  VAL*     3.9     8.7    -      -       +      -
    286A  ALA*     3.2    33.0    -      -       +      +
    361B  ARG*     3.5    27.8    -      -       -      +
----------------------------------------------------------
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Residues in contact with GLN 42 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     38A  ARG      2.8    16.1    +      -       -      +
     39A  PHE*     3.4    10.3    -      -       -      +
     41A  ILE*     1.3    77.9    -      -       -      +
     43A  MET*     1.3    62.1    +      -       -      +
     45A  THR*     3.2    16.0    +      -       -      -
     46A  GLU*     3.5    15.9    +      -       +      +
    119A  ILE*     4.2    22.2    -      -       +      -
    123A  ALA*     5.4     4.3    -      -       +      -
    318B  PRO*     3.4    33.4    -      -       +      +
    319B  ASN*     3.4    36.8    +      -       -      +
    361B  ARG*     5.2     5.2    +      -       -      -
----------------------------------------------------------
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Residues in contact with MET 43 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     39A  PHE*     2.7    39.5    +      -       +      +
     40A  TYR*     3.2    14.1    -      -       -      +
     42A  GLN*     1.3    73.3    -      -       -      +
     44A  CYS*     1.3    58.9    +      -       -      +
     46A  GLU*     2.9    31.3    +      -       +      +
     47A  LEU*     3.1    24.9    -      -       +      +
     63A  ILE*     3.7    26.5    -      -       +      -
     66A  MET*     4.1    17.9    -      -       +      -
    111A  TYR*     5.3     7.6    -      -       +      -
    116A  ILE*     3.7    37.7    -      -       +      -
    119A  ILE*     4.6    15.9    -      -       -      +
----------------------------------------------------------
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Residues in contact with CYS 44 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     40A  TYR*     2.8    56.0    +      -       -      -
     41A  ILE*     2.8    15.1    +      -       +      +
     43A  MET*     1.3    76.5    -      -       -      +
     45A  THR*     1.3    61.3    +      -       +      +
     47A  LEU*     3.8     6.8    +      -       -      -
     48A  LYS*     3.5     1.6    +      -       -      -
     49A  LEU*     3.3    47.4    +      -       +      +
     54A  GLY*     4.4     8.1    -      -       -      -
     63A  ILE*     4.6     2.0    -      -       -      -
----------------------------------------------------------
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Residues in contact with THR 45 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     41A  ILE*     3.6     8.5    +      -       +      +
     42A  GLN*     3.2    14.2    +      -       -      -
     44A  CYS*     1.3    77.1    -      -       +      +
     46A  GLU*     1.3    57.7    +      -       -      +
     47A  LEU      2.9     4.9    -      -       -      -
     48A  LYS*     2.7    39.1    +      -       +      +
     49A  LEU      6.1     0.2    -      -       -      +
    319B  ASN*     3.4    34.4    +      -       -      +
    359B  SER*     5.5     7.6    -      -       -      +
----------------------------------------------------------
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Residues in contact with GLU 46 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     42A  GLN*     3.5    19.1    -      -       +      +
     43A  MET*     2.9    21.5    +      -       +      +
     45A  THR*     1.3    77.2    +      -       -      +
     47A  LEU*     1.3    59.6    +      -       +      +
     48A  LYS*     6.0     0.2    -      -       -      -
    111A  TYR*     2.9    36.8    +      -       +      +
    115A  GLU*     3.9    17.8    -      -       -      +
    118A  ARG*     5.5     1.0    +      -       -      -
    119A  ILE*     4.3    17.1    -      -       +      +
    319B  ASN*     3.9    14.6    -      -       -      +
----------------------------------------------------------
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Residues in contact with LEU 47 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     43A  MET*     3.1    38.0    +      -       +      +
     44A  CYS      4.3     0.2    -      -       -      +
     45A  THR      2.9     0.6    -      -       -      -
     46A  GLU*     1.3    79.7    -      -       +      +
     48A  LYS*     1.3    58.2    +      -       -      +
     49A  LEU*     2.7    40.7    +      -       +      -
     63A  ILE*     4.3    10.1    -      -       +      -
     66A  MET*     5.9     2.0    -      -       -      -
     96A  ILE*     4.0    20.4    -      -       +      -
     98A  ARG*     2.3    39.3    +      -       -      +
    109A  ILE*     4.8    14.4    -      -       +      -
    111A  TYR*     3.8    28.3    -      -       +      -
----------------------------------------------------------
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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