Contacts of the helix formed by residues 102 - 128 (chain C) in PDB entry 2YW7


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 VAL 102 (chain C).
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     42C  VAL*     3.6    15.4    -      -       +      +
     43C  VAL      3.6     2.4    +      -       -      +
     45C  PRO*     3.8    19.2    -      -       +      +
     46C  ASN*     4.0     9.2    -      -       -      +
     47C  PHE*     3.9    12.1    -      -       +      +
     50C  VAL*     3.4    37.5    -      -       +      -
    101C  THR*     1.3    73.0    -      -       -      +
    103C  GLN*     1.3    71.2    +      -       -      +
    105C  HIS*     4.3     5.2    -      -       -      -
    106C  LEU*     2.8    52.9    +      -       +      +
    155C  HIS*     5.0     3.6    -      -       -      +
----------------------------------------------------------
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Residues in contact with GLN 103 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     45A  PRO*     5.4     9.9    -      -       -      +
     45C  PRO*     2.9    35.8    -      -       +      +
     46C  ASN*     5.2     1.0    -      -       -      +
    101C  THR*     3.2    10.5    -      -       +      +
    102C  VAL*     1.3    87.5    -      -       -      +
    104C  ALA*     1.3    58.7    +      -       -      +
    106C  LEU*     6.0     0.2    -      -       -      +
    107C  ALA*     3.5    16.1    -      -       -      +
    155C  HIS      5.4     2.4    +      -       -      -
    156C  LEU*     3.9    28.3    +      -       +      +
----------------------------------------------------------
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Residues in contact with ALA 104 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     97C  VAL*     4.3     8.6    -      -       +      +
    100C  ASP*     3.6    24.9    -      -       +      +
    101C  THR*     2.9    19.0    +      -       -      +
    103C  GLN*     1.3    77.4    -      -       -      +
    105C  HIS*     1.3    61.2    +      -       -      +
    107C  ALA*     3.5     6.4    -      -       -      +
    108C  ALA*     3.0    24.4    +      -       -      +
----------------------------------------------------------
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Residues in contact with HIS 105 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     38C  VAL*     3.3    21.6    -      -       +      +
     41C  ASN*     2.6    36.7    +      -       +      -
     42C  VAL*     3.5    15.7    -      -       +      -
     50C  VAL*     5.9     1.1    -      -       +      -
     95C  TYR*     2.7    32.9    +      +       -      -
     97C  VAL*     3.2    24.7    -      -       +      +
     98C  GLU      3.0    15.9    +      -       -      -
    100C  ASP      3.7     5.3    +      -       -      -
    101C  THR      2.7    28.7    +      -       -      +
    102C  VAL*     3.9     3.1    -      -       -      +
    104C  ALA*     1.3    74.2    -      -       -      +
    106C  LEU*     1.3    56.3    +      -       +      +
    107C  ALA      3.1     1.1    -      -       -      -
    108C  ALA*     2.8     7.4    +      -       -      +
    109C  LEU*     2.8    36.1    +      -       -      +
----------------------------------------------------------
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Residues in contact with LEU 106 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     50C  VAL*     4.2    13.9    -      -       +      -
     53C  MET*     3.8    23.8    -      -       +      -
    102C  VAL*     2.8    34.1    +      -       +      +
    105C  HIS*     1.3    71.6    -      -       -      +
    107C  ALA*     1.3    52.5    +      -       -      +
    109C  LEU*     3.2    12.9    +      -       +      -
    110C  ASP*     2.6    33.0    +      -       -      +
    152C  VAL*     3.2    32.6    -      -       +      +
    155C  HIS*     3.6    41.5    -      -       +      +
    156C  LEU*     3.8    22.4    -      -       +      -
----------------------------------------------------------
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Residues in contact with ALA 107 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    103C  GLN      3.5    17.4    +      -       -      +
    104C  ALA*     3.5    12.1    -      -       -      +
    106C  LEU*     1.3    78.6    -      -       -      +
    108C  ALA*     1.3    63.0    +      -       -      +
    110C  ASP*     3.2    22.0    +      -       -      +
    111C  LEU*     3.3    15.5    +      -       +      +
    156C  LEU*     4.0    12.0    -      -       +      +
----------------------------------------------------------
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Residues in contact with ALA 108 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     95C  TYR*     3.2    30.1    -      -       +      +
     97C  VAL*     3.5    21.3    -      -       +      -
    104C  ALA      3.0     8.4    +      -       -      +
    105C  HIS      2.8    14.0    +      -       -      +
    107C  ALA*     1.3    71.4    -      -       -      +
    109C  LEU*     1.3    61.2    +      -       -      +
    111C  LEU*     3.2    12.2    +      -       -      +
    112C  VAL*     3.1    25.4    +      -       -      +
----------------------------------------------------------
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Residues in contact with LEU 109 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     31C  LEU*     5.6     0.2    -      -       +      -
     34C  THR*     4.8     5.6    -      -       +      -
     35C  LEU*     3.8    24.9    -      -       +      -
     38C  VAL*     3.9    38.8    -      -       +      -
     54C  ILE*     4.1    26.0    -      -       +      -
     95C  TYR*     4.7     0.7    -      -       +      +
    105C  HIS      2.8    16.5    +      -       -      +
    106C  LEU*     3.6    19.3    -      -       +      +
    108C  ALA*     1.3    69.7    -      -       -      +
    110C  ASP*     1.3    67.9    +      -       -      +
    112C  VAL*     3.5    15.0    -      -       +      +
    113C  TYR*     3.0    42.8    +      -       +      -
    148C  PHE*     4.9     6.3    -      -       +      -
    152C  VAL*     4.3     7.2    -      -       +      -
----------------------------------------------------------
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Residues in contact with ASP 110 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    106C  LEU      2.6    18.0    +      -       -      +
    107C  ALA*     3.2    15.0    -      -       -      +
    109C  LEU*     1.3    75.2    -      -       -      +
    111C  LEU*     1.3    61.8    +      -       -      +
    113C  TYR*     3.5     4.0    +      -       -      +
    114C  ASN*     3.1    33.7    +      -       -      -
    149C  GLN*     3.3    15.0    +      -       -      +
    152C  VAL*     4.0     9.3    -      -       +      +
    153C  ARG*     3.0    43.5    +      -       -      +
    156C  LEU*     5.4     5.6    -      -       +      -
----------------------------------------------------------
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Residues in contact with LEU 111 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    107C  ALA*     3.3    15.5    +      -       +      +
    108C  ALA*     3.2     8.9    +      -       -      +
    109C  LEU      3.2     0.4    -      -       -      -
    110C  ASP*     1.3    81.1    -      -       -      +
    112C  VAL*     1.3    66.7    +      -       -      +
    113C  TYR      3.2     0.2    -      -       -      -
    114C  ASN*     3.1    37.7    -      -       +      +
    115C  GLY*     3.3     3.5    +      -       -      -
----------------------------------------------------------
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Residues in contact with VAL 112 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     31C  LEU*     4.8    13.9    -      -       +      -
     34C  THR*     4.9     8.5    -      -       +      +
     92C  TRP*     5.4    15.9    +      -       +      +
     95C  TYR*     4.1    21.3    -      -       +      -
    108C  ALA      3.1    19.3    +      -       -      +
    109C  LEU*     3.5    20.0    -      -       +      +
    111C  LEU*     1.3    73.5    -      -       -      +
    113C  TYR*     1.3    68.8    +      -       +      +
    115C  GLY*     3.0    17.3    +      -       -      -
    116C  VAL*     3.1    23.5    +      -       +      +
----------------------------------------------------------
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Residues in contact with TYR 113 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     31C  LEU*     3.5    30.0    -      -       +      +
     35C  LEU*     3.5     7.4    -      -       +      +
     57C  GLN*     2.6    44.1    +      -       -      +
    109C  LEU*     3.0    32.0    +      -       +      +
    112C  VAL*     1.3    79.2    -      -       +      +
    114C  ASN*     1.3    66.6    +      -       -      +
    115C  GLY      2.9     2.2    -      -       -      -
    116C  VAL*     4.2     7.6    -      -       +      +
    117C  ILE*     2.7    47.2    +      -       +      +
    145C  LEU*     3.6    25.6    -      -       +      -
    148C  PHE*     3.2    26.4    -      +       -      -
    149C  GLN*     3.3    26.9    -      -       +      -
    152C  VAL*     5.1     1.6    -      -       +      -
----------------------------------------------------------
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Residues in contact with ASN 114 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    110C  ASP*     3.1    30.4    +      -       -      -
    111C  LEU*     3.1    37.1    -      -       +      +
    113C  TYR*     1.3    74.3    -      -       -      +
    115C  GLY*     1.3    57.3    +      -       -      +
    117C  ILE*     4.2     3.6    -      -       -      +
    118C  GLU*     3.3    22.2    +      -       -      +
    149C  GLN*     4.4    11.2    +      -       -      +
    153C  ARG*     4.2    16.2    +      -       -      +
----------------------------------------------------------
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Residues in contact with GLY 115 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    111C  LEU      3.3     3.0    +      -       -      -
    112C  VAL      3.0     8.2    +      -       -      -
    113C  TYR      2.9     2.0    +      -       -      -
    114C  ASN*     1.3    77.7    -      -       -      +
    116C  VAL*     1.3    65.3    +      -       -      +
    118C  GLU*     3.0    17.2    +      -       -      +
    119C  ASP*     3.0    23.5    +      -       -      -
----------------------------------------------------------
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Residues in contact with VAL 116 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     27C  THR*     4.2    29.8    -      -       +      +
     28C  TYR*     4.7     7.9    -      -       +      -
     31C  LEU*     4.1    28.7    -      -       +      -
     92C  TRP*     5.7     5.6    -      -       +      +
    112C  VAL*     3.1    24.2    +      -       +      +
    113C  TYR*     3.9    10.5    -      -       +      +
    115C  GLY*     1.3    72.7    -      -       -      +
    117C  ILE*     1.3    59.5    +      -       -      +
    119C  ASP*     3.6     1.8    +      -       -      +
    120C  THR*     2.4    40.6    +      -       -      +
    145C  LEU*     4.1    24.5    -      -       +      -
----------------------------------------------------------
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Residues in contact with ILE 117 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    113C  TYR*     2.7    59.6    +      -       +      +
    114C  ASN*     4.2     4.0    -      -       -      +
    116C  VAL*     1.3    74.2    -      -       +      +
    118C  GLU*     1.3    67.3    +      -       +      +
    120C  THR*     3.5     6.5    -      -       -      -
    121C  ARG*     3.1    56.1    +      -       -      +
    142C  ALA*     5.9     1.2    -      -       -      +
    145C  LEU*     3.9    15.7    -      -       +      +
    146C  GLU*     3.5    24.9    -      -       +      +
    149C  GLN*     3.6    25.8    -      -       +      +
----------------------------------------------------------
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Residues in contact with GLU 118 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    114C  ASN      3.3    16.5    +      -       -      +
    115C  GLY*     3.0     8.7    +      -       -      +
    117C  ILE*     1.3    78.1    -      -       +      +
    119C  ASP*     1.3    74.8    +      -       -      +
    121C  ARG*     2.7    23.2    +      -       +      +
    122C  LYS*     2.8    19.2    +      -       +      -
----------------------------------------------------------
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Residues in contact with ASP 119 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     24C  GLN*     4.9     7.0    -      -       -      +
     27C  THR*     4.7    12.2    +      -       +      +
     91C  THR*     4.6    16.4    -      -       -      +
     92C  TRP*     4.6    10.9    -      -       -      -
    115C  GLY*     3.0    19.9    +      -       -      +
    116C  VAL*     4.0     3.6    -      -       -      +
    118C  GLU*     1.3    83.3    -      -       -      +
    120C  THR*     1.3    66.9    +      -       -      +
    122C  LYS*     2.8    30.9    +      -       -      +
    123C  SER*     3.1     6.9    +      -       -      -
----------------------------------------------------------
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Residues in contact with THR 120 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     24C  GLN*     3.6    33.0    +      -       -      +
     27C  THR*     6.1     0.2    -      -       -      +
     28C  TYR*     4.8     2.7    -      -       -      +
    116C  VAL*     2.4    34.9    +      -       -      +
    117C  ILE*     3.5     7.0    -      -       -      -
    119C  ASP*     1.3    76.3    -      -       -      +
    121C  ARG*     1.3    57.0    +      -       -      +
    123C  SER*     3.3     2.2    +      -       -      -
    124C  ILE*     2.9    40.6    +      -       +      +
    138C  LEU*     3.5    28.9    -      -       +      +
    141C  HIS*     5.2     0.4    -      -       +      -
    142C  ALA*     3.9    16.4    -      -       +      +
    145C  LEU*     4.9     4.3    -      -       +      +
----------------------------------------------------------
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Residues in contact with ARG 121 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    117C  ILE*     3.1    38.2    +      -       -      +
    118C  GLU*     2.7    17.2    +      -       +      +
    120C  THR*     1.3    68.4    -      -       -      +
    122C  LYS*     1.3    52.9    +      -       -      +
    123C  SER      2.6    16.4    +      -       -      -
    124C  ILE*     3.7    10.1    -      -       +      +
    125C  GLU*     2.7    27.4    +      -       -      +
    142C  ALA*     5.7     3.6    -      -       +      -
    146C  GLU*     2.7    34.4    +      -       -      +
    149C  GLN*     5.8     0.6    +      -       -      -
     75E  LEU*     5.7     5.7    -      -       -      +
    131E  ASP*     5.8     2.3    +      -       -      -
    133E  VAL*     5.9     3.8    -      -       +      -
----------------------------------------------------------
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Residues in contact with LYS 122 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    118C  GLU*     2.8    21.6    +      -       +      +
    119C  ASP*     3.0    13.2    -      -       -      +
    121C  ARG*     1.3    67.9    -      -       -      +
    123C  SER*     1.3    56.1    +      -       -      +
    125C  GLU*     3.1    37.1    -      -       -      +
    126C  LYS*     4.1    13.4    -      -       +      +
----------------------------------------------------------
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Residues in contact with SER 123 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     20C  LEU*     3.7    29.6    +      -       -      +
     24C  GLN*     4.7     5.6    +      -       -      -
    119C  ASP      3.2    17.0    -      -       -      -
    120C  THR*     3.4     7.4    -      -       -      -
    121C  ARG      2.6     8.3    +      -       -      -
    122C  LYS*     1.3    73.5    -      -       -      +
    124C  ILE*     1.3    59.5    +      -       -      -
    125C  GLU      3.0     1.5    -      -       -      +
    126C  LYS*     2.9    20.7    +      -       -      +
    127C  LEU*     3.1    23.5    +      -       -      +
    138C  LEU*     4.1    12.1    -      -       -      +
----------------------------------------------------------
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Residues in contact with ILE 124 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    120C  THR*     2.9    24.8    +      -       +      +
    121C  ARG*     3.8     8.1    -      -       +      +
    123C  SER*     1.3    74.8    -      -       -      +
    125C  GLU*     1.3    61.0    -      -       -      +
    127C  LEU*     3.4     7.4    +      -       -      -
    128C  GLU*     4.9     0.2    -      -       -      +
    135C  GLN*     2.4    47.0    +      -       +      +
    138C  LEU*     3.3    45.2    -      -       +      +
    139C  ILE*     3.4    31.9    -      -       +      -
    142C  ALA*     3.8    15.3    -      -       +      -
    132E  LEU*     4.4    11.3    -      -       +      +
    133E  VAL*     5.1     4.5    -      -       +      -
----------------------------------------------------------
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Residues in contact with GLU 125 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    121C  ARG      2.7    17.3    +      -       -      +
    122C  LYS*     3.1    46.5    -      -       -      +
    124C  ILE*     1.3    79.9    -      -       -      +
    126C  LYS*     1.3    66.2    +      -       -      +
    127C  LEU      3.4     0.6    +      -       -      -
    128C  GLU*     4.8     7.6    +      -       -      +
    129C  ASP*     5.5     1.9    -      -       -      +
    132E  LEU*     6.5     0.2    -      -       -      -
----------------------------------------------------------
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Residues in contact with LYS 126 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     20C  LEU*     3.9    26.4    -      -       +      +
    122C  LYS*     4.1    17.9    -      -       +      +
    123C  SER*     2.9    13.6    +      -       -      +
    125C  GLU*     1.3    92.7    -      -       -      +
    127C  LEU*     1.3    56.3    +      -       -      +
    128C  GLU      3.8     0.7    -      -       -      -
    129C  ASP*     4.2     6.3    -      -       -      +
    130C  LEU*     3.5    23.5    -      -       -      +
----------------------------------------------------------
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Residues in contact with LEU 127 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     17C  VAL*     3.9    29.6    -      -       +      +
     20C  LEU*     3.8    21.5    -      -       +      -
     21C  LEU*     4.8     3.4    -      -       +      -
    123C  SER      3.1    16.3    +      -       -      +
    124C  ILE*     3.4     5.3    +      -       -      +
    125C  GLU      3.4     1.4    -      -       -      -
    126C  LYS*     1.3    77.8    -      -       -      +
    128C  GLU*     1.3    59.1    +      -       -      +
    129C  ASP      3.2     2.7    -      -       -      -
    130C  LEU*     2.7    40.5    +      -       +      -
    131C  ASP      3.2    16.0    +      -       -      +
    134C  SER*     4.1     6.7    -      -       -      -
    135C  GLN*     3.9    32.3    -      -       +      +
    138C  LEU*     3.8    26.0    -      -       +      -
----------------------------------------------------------
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Residues in contact with GLU 128 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    124C  ILE      4.9     1.3    -      -       -      +
    125C  GLU*     4.8     6.8    +      -       -      +
    126C  LYS      3.8     1.2    -      -       -      -
    127C  LEU*     1.3    76.0    -      -       -      +
    129C  ASP*     1.3    71.2    +      -       -      +
    130C  LEU      3.3     0.9    +      -       -      +
    132C  LEU*     3.1    36.1    -      -       +      +
    135C  GLN*     3.1    30.8    +      -       -      +
    128E  GLU*     5.9     2.9    -      -       -      +
    132E  LEU*     4.1    18.3    -      -       -      +
    128J  GLU*     3.2    22.6    -      -       -      +
----------------------------------------------------------
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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