Contacts of the helix formed by residues 76 - 99 (chain A) in PDB entry 3RR1


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 GLY 76 (chain A).
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     75A  GLY*     1.3    73.1    -      -       -      -
     77A  PRO*     1.3    76.9    -      -       -      +
     78A  ILE      3.3     2.6    +      -       -      -
     79A  LEU      3.6     0.2    +      -       -      -
     80A  MET*     3.0    26.4    +      -       -      +
    238A  PHE*     4.0    13.5    -      -       -      -
    405A   CL      3.1    11.1    -      -       -      +
     76B  GLY*     4.4     2.0    -      -       -      -
     77B  PRO*     3.7    10.2    -      -       -      +
----------------------------------------------------------
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Residues in contact with PRO 77 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     76A  GLY*     1.3    83.1    -      -       -      +
     78A  ILE*     1.3    59.0    +      -       -      +
     81A  SER*     2.7    28.6    +      -       -      -
    238A  PHE*     3.7    21.9    -      -       +      -
    261A  HIS*     2.8    23.8    +      -       +      +
     72B  PHE*     3.8    16.2    -      -       +      -
     73B  TYR*     4.0     5.2    -      -       +      -
     74B  ARG      3.6    14.6    -      -       -      +
     75B  GLY      3.4    29.2    -      -       -      +
     76B  GLY*     4.1     0.7    -      -       -      +
     79B  LEU*     4.1    10.1    -      -       +      -
    405B   CL      3.8     6.1    -      -       +      -
----------------------------------------------------------
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Residues in contact with ILE 78 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     37A  ARG*     4.0    12.8    -      -       +      -
     40A  THR*     3.8    36.3    -      -       +      +
     41A  VAL*     4.1    12.6    -      -       +      +
     44A  ALA*     3.9    20.9    -      -       +      -
     76A  GLY      3.3     0.4    -      -       -      -
     77A  PRO*     1.3    74.9    -      -       -      +
     79A  LEU*     1.3    65.8    +      -       -      +
     81A  SER*     3.3     5.2    +      -       -      -
     82A  ALA*     3.1    20.6    +      -       -      +
    405A   CL      3.5     8.2    -      -       +      +
     40B  THR*     4.1     7.6    -      -       +      -
     72B  PHE*     3.6    28.7    -      -       +      -
     78B  ILE*     4.4     4.7    -      -       +      -
     79B  LEU*     3.9    15.5    -      -       +      -
    405B   CL      3.7    16.6    -      -       +      -
----------------------------------------------------------
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Residues in contact with LEU 79 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     44A  ALA*     4.3    19.5    -      -       +      -
     48A  LEU*     4.4    13.1    -      -       +      +
     67A  MET      6.2     0.4    -      -       -      +
     72A  PHE*     3.6    35.4    -      -       +      -
     73A  TYR      4.1     3.8    -      -       -      +
     75A  GLY*     3.7    28.7    -      -       -      +
     78A  ILE*     1.3    78.7    -      -       -      +
     80A  MET*     1.3    58.0    +      -       -      +
     82A  ALA*     3.3     4.4    +      -       -      +
     83A  ILE*     2.9    39.7    +      -       +      +
    405A   CL      3.2    12.9    -      -       +      +
     37B  ARG*     4.0    25.6    -      -       -      +
     77B  PRO*     4.5     1.1    -      -       +      -
     78B  ILE*     4.0    11.7    -      -       +      -
----------------------------------------------------------
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Residues in contact with MET 80 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     64A  TRP*     4.0    27.4    -      -       +      -
     68A  TYR*     3.8    31.9    -      -       +      -
     75A  GLY*     3.6    20.0    -      -       -      +
     76A  GLY      3.0    22.9    +      -       -      +
     79A  LEU*     1.3    73.6    -      -       -      +
     81A  SER*     1.3    59.6    +      -       -      +
     83A  ILE*     4.2     9.9    -      -       +      -
     84A  ALA*     2.8    25.5    +      -       -      +
    238A  PHE*     3.4    34.3    -      -       +      +
    239A  SER*     4.2     8.5    -      -       -      -
    261A  HIS*     3.1    24.4    -      -       +      +
    262A  ALA      4.6     0.7    -      -       -      +
    263A  GLY*     3.6    13.1    +      -       -      -
    267A  GLU*     5.0     0.7    -      -       +      -
----------------------------------------------------------
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Residues in contact with SER 81 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     32A  PRO*     3.4    11.4    -      -       -      +
     33A  VAL*     3.7    23.2    +      -       -      +
     41A  VAL*     4.5     7.4    -      -       -      +
     77A  PRO      2.7    24.2    +      -       -      -
     78A  ILE      3.3     4.6    +      -       -      -
     79A  LEU      3.3     0.4    -      -       -      -
     80A  MET*     1.3    75.9    -      -       -      +
     82A  ALA*     1.3    64.5    +      -       -      +
     84A  ALA*     3.2     2.8    +      -       -      +
     85A  GLY      3.1    18.5    +      -       -      -
    260A  SER      3.6    13.9    +      -       -      -
    261A  HIS*     2.9    23.1    +      -       -      -
     72B  PHE*     5.5     0.5    -      -       -      -
----------------------------------------------------------
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Residues in contact with ALA 82 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     32A  PRO*     4.7     0.4    -      -       -      -
     41A  VAL*     4.3     4.4    -      -       +      +
     44A  ALA*     3.8    16.4    -      -       +      -
     45A  VAL*     3.7    40.8    -      -       +      +
     48A  LEU*     3.8    13.5    -      -       +      -
     78A  ILE      3.1     8.1    +      -       -      +
     79A  LEU      3.3     6.9    +      -       -      +
     81A  SER*     1.3    74.8    -      -       -      +
     83A  ILE*     1.3    63.6    +      -       -      +
     85A  GLY*     3.3     2.8    +      -       -      -
     86A  ILE*     3.1    27.7    +      -       -      +
----------------------------------------------------------
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Residues in contact with ILE 83 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     48A  LEU*     3.7    18.8    -      -       +      -
     64A  TRP*     3.3    38.4    -      -       +      +
     67A  MET*     3.8    22.8    -      -       +      +
     68A  TYR*     3.7    37.5    -      -       +      +
     75A  GLY*     6.1     0.2    -      -       -      -
     79A  LEU*     2.9    25.5    +      -       +      +
     80A  MET*     3.8    19.3    -      -       +      +
     82A  ALA*     1.3    74.1    -      -       -      +
     84A  ALA*     1.3    59.6    +      -       -      +
     86A  ILE*     3.2     2.1    +      -       -      +
     87A  ASP*     2.9    28.2    +      -       -      +
    263A  GLY*     4.1     5.6    -      -       -      +
----------------------------------------------------------
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Residues in contact with ALA 84 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     80A  MET      2.8    22.5    +      -       -      +
     81A  SER      3.2     1.8    +      -       -      +
     83A  ILE*     1.3    75.0    -      -       -      +
     85A  GLY*     1.3    61.4    +      -       -      +
     87A  ASP*     3.7     1.4    -      -       -      +
     88A  GLN*     3.1    30.6    +      -       -      +
    259A  LEU      3.3    23.1    -      -       -      +
    260A  SER*     3.5    21.3    -      -       -      -
    263A  GLY      3.7     2.5    -      -       -      +
    264A  GLY*     3.3    19.3    -      -       -      +
----------------------------------------------------------
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Residues in contact with GLY 85 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     18A  LEU*     3.7    18.6    -      -       -      +
     30A  GLY*     3.3    13.0    -      -       -      -
     31A  GLU      4.0     7.6    -      -       -      -
     32A  PRO*     4.0    18.1    -      -       -      +
     81A  SER      3.1    13.2    +      -       -      -
     82A  ALA      3.3     3.3    +      -       -      -
     84A  ALA*     1.3    73.8    -      -       -      +
     86A  ILE*     1.3    65.6    +      -       -      +
     88A  GLN*     4.4     0.7    -      -       -      -
     89A  ALA      3.3    15.9    +      -       -      -
----------------------------------------------------------
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Residues in contact with ILE 86 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
      6A  LEU*     4.1    16.2    -      -       +      -
     18A  LEU*     4.1    13.2    -      -       +      -
     20A  VAL*     5.3     2.7    -      -       +      -
     45A  VAL*     4.1    13.5    -      -       +      +
     48A  LEU*     3.7    22.7    -      -       +      -
     52A  LEU*     3.6    27.4    -      -       +      -
     67A  MET*     3.6    34.5    -      -       +      -
     82A  ALA      3.1    17.9    +      -       -      +
     83A  ILE      3.9     3.1    -      -       -      +
     85A  GLY*     1.3    75.6    -      -       -      +
     87A  ASP*     1.3    64.4    +      -       -      +
     89A  ALA*     3.1     5.9    +      -       -      +
     90A  LEU*     2.9    36.0    +      -       +      +
----------------------------------------------------------
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Residues in contact with ASP 87 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     60A  ILE*     3.4    12.1    -      -       -      +
     64A  TRP*     3.4    12.0    -      -       +      +
     67A  MET*     4.9     2.2    -      -       +      +
     83A  ILE      2.9    17.1    +      -       -      +
     84A  ALA      3.7     4.5    -      -       -      +
     86A  ILE*     1.3    78.2    -      -       -      +
     88A  GLN*     1.3    61.0    +      -       -      +
     90A  LEU*     3.3     9.9    +      -       -      +
     91A  TRP*     3.0    30.2    +      -       -      -
    263A  GLY      3.9    12.8    -      -       -      +
    264A  GLY*     4.2     0.4    -      -       -      -
    265A  ILE      2.8    27.0    +      -       -      -
    266A  THR*     2.6    35.8    +      -       -      -
----------------------------------------------------------
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Residues in contact with GLN 88 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     29A  TRP      3.7     4.3    -      -       -      +
     30A  GLY*     3.9     4.9    -      -       -      -
     31A  GLU*     2.7    37.4    +      -       -      +
     84A  ALA      3.1    17.7    +      -       -      +
     85A  GLY      3.7     3.6    -      -       -      +
     86A  ILE      3.3     0.2    -      -       -      -
     87A  ASP*     1.3    76.9    +      -       -      +
     89A  ALA*     1.3    58.6    +      -       -      +
     91A  TRP*     3.3     6.4    +      -       -      +
     92A  ASP*     2.9    27.2    +      -       -      +
    259A  LEU      3.1    27.9    +      -       -      +
    260A  SER*     3.1    20.8    +      -       -      +
    264A  GLY*     4.8     5.8    -      -       -      -
    265A  ILE*     4.7     5.8    -      -       +      -
    291A  ILE*     3.6     9.3    -      -       -      +
    292A  ALA*     4.4     2.1    +      -       -      +
    295A  ALA*     3.9    26.1    -      -       +      +
    348A  LEU*     3.7    10.4    -      -       +      +
----------------------------------------------------------
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Residues in contact with ALA 89 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     18A  LEU*     3.8    10.1    -      -       +      -
     20A  VAL*     3.5    27.8    -      -       +      -
     28A  GLY*     3.5     7.0    -      -       -      +
     29A  TRP      3.3    28.4    +      -       -      +
     85A  GLY      3.3     1.8    +      -       -      -
     86A  ILE      3.1     9.2    +      -       -      +
     88A  GLN*     1.3    80.0    -      -       -      +
     90A  LEU*     1.3    57.6    +      -       -      +
     92A  ASP*     3.2     3.7    +      -       -      +
     93A  ILE*     2.9    34.0    +      -       -      +
----------------------------------------------------------
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Residues in contact with LEU 90 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
      3A  ILE*     4.0    15.3    -      -       +      -
     20A  VAL*     4.6     6.3    -      -       +      -
     52A  LEU*     4.7     1.1    -      -       +      -
     57A  PRO*     3.9    28.8    -      -       +      +
     60A  ILE*     3.6    35.8    -      -       +      +
     63A  LEU*     3.8    33.0    -      -       +      -
     64A  TRP      5.5     0.2    -      -       -      +
     67A  MET*     4.9     3.1    -      -       +      -
     86A  ILE*     2.9    37.3    +      -       +      +
     87A  ASP*     3.3     9.6    +      -       -      +
     89A  ALA*     1.3    72.5    -      -       -      +
     91A  TRP*     1.3    60.6    +      -       -      +
     93A  ILE*     3.2    14.1    +      -       +      +
     94A  LYS*     3.0    23.9    +      -       -      +
----------------------------------------------------------
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Residues in contact with TRP 91 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     60A  ILE*     3.6    20.6    -      -       +      +
     61A  ASN*     6.0     3.4    -      -       -      -
     87A  ASP*     3.0    38.2    +      -       -      -
     88A  GLN      3.6     6.7    -      -       -      +
     90A  LEU*     1.3    72.9    -      -       -      +
     92A  ASP*     1.3    66.1    +      -       -      +
     94A  LYS*     3.3    15.1    +      -       +      +
     95A  GLY      3.0    19.6    +      -       -      -
    102A  VAL*     3.5    29.4    -      -       +      +
    105A  LEU*     3.8    36.1    -      -       +      -
    106A  LEU*     3.7    29.8    -      -       +      -
    265A  ILE*     3.6    33.7    -      -       +      +
    266A  THR*     3.0    26.6    +      -       +      +
    348A  LEU*     4.9     0.2    -      -       +      -
----------------------------------------------------------
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Residues in contact with ASP 92 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     28A  GLY*     3.4     1.4    -      -       -      -
     29A  TRP*     2.9    34.1    +      -       -      +
     88A  GLN      2.9    13.8    +      -       -      +
     89A  ALA      3.2     9.2    +      -       -      +
     91A  TRP*     1.3    77.2    -      -       -      +
     93A  ILE*     1.3    61.6    +      -       -      +
     96A  LYS*     3.1    57.4    +      -       -      +
    346A  PRO      4.2     0.3    -      -       -      +
    347A  GLY*     3.4     3.1    -      -       -      -
    348A  LEU*     2.9    43.2    +      -       +      +
    349A  GLY      4.4     1.2    +      -       -      -
    350A  VAL*     5.0     6.1    -      -       -      +
----------------------------------------------------------
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Residues in contact with ILE 93 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
      1A  VAL*     5.5     1.1    -      -       +      -
     20A  VAL*     3.7    33.0    -      -       +      +
     22A  THR*     3.9    14.8    -      -       +      -
     26A  VAL*     4.1    15.9    -      -       +      +
     27A  THR      4.0     3.8    -      -       -      -
     28A  GLY*     3.5    22.4    -      -       -      +
     57A  PRO*     4.0    26.2    -      -       +      -
     58A  SER*     6.4     0.2    -      -       -      -
     89A  ALA      2.9    20.0    +      -       -      +
     90A  LEU*     3.5    15.9    -      -       +      +
     91A  TRP      3.2     0.2    -      -       -      -
     92A  ASP*     1.3    74.7    -      -       -      +
     94A  LYS*     1.3    55.9    +      -       -      +
     96A  LYS*     3.1     4.5    +      -       -      +
     97A  VAL*     2.8    47.6    +      -       +      +
----------------------------------------------------------
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Residues in contact with LYS 94 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     57A  PRO      5.6     0.7    -      -       -      +
     58A  SER*     2.9    45.1    +      -       -      +
     60A  ILE*     3.7    19.1    -      -       +      -
     90A  LEU      3.0    15.6    +      -       -      +
     91A  TRP*     3.8    28.9    -      -       +      +
     93A  ILE*     1.3    77.1    -      -       -      +
     95A  GLY*     1.3    58.1    +      -       -      +
     97A  VAL*     3.4     5.1    +      -       -      +
     98A  LEU*     2.9    48.6    +      -       +      +
    105A  LEU*     3.8    12.8    -      -       +      -
----------------------------------------------------------
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Residues in contact with GLY 95 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     91A  TRP      3.0    12.0    +      -       -      -
     94A  LYS*     1.3    77.1    -      -       -      +
     96A  LYS*     1.3    55.8    +      -       -      +
     98A  LEU      3.4     0.2    +      -       -      -
     99A  GLY*     2.8    24.3    +      -       -      -
    100A  VAL*     2.9    32.2    +      -       -      -
    102A  VAL*     4.8     0.7    -      -       -      -
    105A  LEU*     3.9    13.8    -      -       -      +
    346A  PRO*     3.6     0.3    -      -       -      +
    347A  GLY*     3.6    13.9    -      -       -      -
----------------------------------------------------------
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Residues in contact with LYS 96 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     26A  VAL*     3.7    19.0    -      -       +      +
     27A  THR*     2.7    31.5    +      -       -      +
     29A  TRP*     4.5     8.3    -      -       -      -
     92A  ASP*     3.1    36.0    +      -       -      +
     93A  ILE      3.1     7.9    +      -       -      +
     95A  GLY*     1.3    73.7    -      -       -      +
     97A  VAL*     1.3    64.6    +      -       -      +
     99A  GLY*     3.3    10.9    +      -       -      -
    346A  PRO*     3.8    28.0    -      -       +      +
    350A  VAL      4.8     9.9    +      -       -      -
----------------------------------------------------------
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Residues in contact with VAL 97 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
      1A  VAL*     5.1    20.6    -      -       +      -
     26A  VAL*     4.2    20.0    -      -       +      -
     93A  ILE*     2.8    37.4    +      -       +      +
     94A  LYS*     3.7     7.4    -      -       +      +
     96A  LYS*     1.3    74.2    -      -       -      +
     98A  LEU*     1.3    73.7    +      -       +      +
     99A  GLY      3.5     0.3    +      -       -      -
----------------------------------------------------------
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Residues in contact with LEU 98 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     94A  LYS*     2.9    36.0    +      -       +      +
     97A  VAL*     1.3    88.1    -      -       +      +
     99A  GLY*     1.3    61.9    +      -       -      +
    100A  VAL*     3.4    12.0    +      -       +      +
    105A  LEU*     3.7    32.3    -      -       +      -
----------------------------------------------------------
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Residues in contact with GLY 99 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     95A  GLY      2.8     8.9    +      -       -      -
     96A  LYS      3.3     7.5    +      -       -      -
     97A  VAL      3.3     5.1    +      -       -      -
     98A  LEU*     1.3    77.7    -      -       -      +
    100A  VAL*     1.3    62.4    +      -       -      +
    101A  PRO*     4.9     0.3    -      -       -      +
    346A  PRO*     3.8    21.1    -      -       -      +
----------------------------------------------------------
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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