Contacts of the helix formed by residues 266 - 292 (chain A) in PDB entry 3RFM


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 PRO 266 (chain A).
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    263A  SER*     5.3     0.9    -      -       -      +
    264A  HIS      3.3     7.3    -      -       -      +
    265A  ALA*     1.3    93.0    -      -       +      +
    267A  LEU*     1.3    60.0    +      -       -      +
    268A  TRP*     3.3    37.0    -      -       +      +
    269A  LEU*     3.5    20.4    +      -       +      -
    270A  MET*     2.9    23.8    +      -       -      +
----------------------------------------------------------
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Residues in contact with LEU 267 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    265A  ALA      5.4     2.0    -      -       -      +
    266A  PRO*     1.3    71.3    -      -       -      +
    268A  TRP*     1.3    67.3    +      -       -      +
    269A  LEU      3.1     0.4    -      -       -      -
    270A  MET*     3.0    24.7    +      -       +      +
    271A  TYR*     3.0    17.5    +      -       -      +
----------------------------------------------------------
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Residues in contact with TRP 268 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    266A  PRO*     3.3    34.7    -      -       +      +
    267A  LEU*     1.3    79.3    -      -       -      +
    269A  LEU*     1.3    89.4    +      -       +      +
    271A  TYR*     2.8    39.6    -      +       +      -
    272A  LEU*     3.8    17.6    +      -       +      +
----------------------------------------------------------
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Residues in contact with LEU 269 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    252A  ILE*     4.1    21.1    -      -       +      +
    265A  ALA*     4.6     4.0    -      -       +      -
    266A  PRO*     3.5    33.5    +      -       +      +
    267A  LEU      3.1     0.2    -      -       -      -
    268A  TRP*     1.3   108.9    -      -       +      +
    270A  MET*     1.3    65.6    +      -       -      +
    271A  TYR      3.4     0.2    -      -       -      -
    272A  LEU*     3.4    18.3    +      -       +      +
    273A  ALA*     3.3    20.1    +      -       -      +
----------------------------------------------------------
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Residues in contact with MET 270 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    249A  LEU*     4.5    11.9    -      -       -      -
    252A  ILE*     3.7    32.5    -      -       +      +
    253A  ASN*     4.8     2.0    -      -       -      +
    256A  THR*     5.6     2.2    -      -       -      +
    265A  ALA*     3.9    20.0    -      -       +      +
    266A  PRO      2.9    15.7    +      -       -      +
    267A  LEU*     3.0    20.6    +      -       +      +
    269A  LEU*     1.3    77.8    -      -       -      +
    271A  TYR*     1.3    62.8    +      -       -      +
    273A  ALA*     3.3     6.1    +      -       -      +
    274A  ILE*     3.0    36.1    +      -       +      +
    330A  CFF      3.6    35.9    -      -       +      -
----------------------------------------------------------
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Residues in contact with TYR 271 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
      9A  TYR*     3.4    42.8    -      +       +      -
     12A  VAL*     6.5     0.4    -      -       +      -
    267A  LEU      3.0     9.3    +      -       -      +
    268A  TRP*     2.8    44.9    -      +       +      -
    270A  MET*     1.3    73.9    -      -       -      +
    272A  LEU*     1.3    68.6    +      -       +      +
    274A  ILE*     2.9    13.3    +      -       +      +
    275A  VAL*     2.6    51.4    +      -       +      +
----------------------------------------------------------
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Residues in contact with LEU 272 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    248A  PRO*     6.3     0.9    -      -       +      -
    268A  TRP*     4.0    26.9    -      -       +      +
    269A  LEU*     3.4    19.9    +      -       +      +
    270A  MET      3.2     0.4    -      -       -      -
    271A  TYR*     1.3    97.9    -      -       +      +
    273A  ALA*     1.3    62.1    +      -       +      +
    275A  VAL*     3.9     4.3    -      -       -      +
    276A  LEU*     2.9    36.6    +      -       +      +
----------------------------------------------------------
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Residues in contact with ALA 273 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    245A  CYS      4.5     1.2    -      -       -      +
    248A  PRO*     4.5     4.0    -      -       +      -
    249A  LEU*     3.6    49.7    +      -       +      +
    252A  ILE*     3.9    20.2    -      -       +      -
    269A  LEU      3.3     2.5    +      -       -      +
    270A  MET      3.3     6.8    +      -       -      +
    271A  TYR      3.2     0.4    -      -       -      -
    272A  LEU*     1.3    83.6    -      -       +      +
    274A  ILE*     1.3    61.4    +      -       -      +
    276A  LEU*     3.6    10.1    +      -       -      +
    277A  ALA*     3.4    14.4    +      -       -      +
----------------------------------------------------------
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Residues in contact with ILE 274 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
      9A  TYR*     4.3    14.4    -      -       -      +
     63A  ALA*     5.0     0.2    -      -       +      -
    249A  LEU*     4.2    15.7    -      -       +      -
    270A  MET*     3.0    23.1    -      -       +      +
    271A  TYR*     2.9    13.9    +      -       +      +
    273A  ALA*     1.3    76.5    -      -       -      +
    275A  VAL*     1.3    63.1    +      -       -      +
    277A  ALA*     3.2    12.1    +      -       +      +
    278A  HIS*     2.9    45.0    +      -       +      +
    330A  CFF      3.3    61.0    -      -       +      +
----------------------------------------------------------
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Residues in contact with VAL 275 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
      9A  TYR*     3.6     7.9    -      -       +      -
     12A  VAL*     4.4    16.4    -      -       +      -
     13A  GLU*     3.1    24.9    -      -       +      +
     16A  ILE*     3.8    21.7    -      -       +      +
    271A  TYR*     2.6    47.8    +      -       +      +
    272A  LEU*     3.9     5.8    -      -       -      +
    274A  ILE*     1.3    72.3    -      -       -      +
    276A  LEU*     1.3    61.4    +      -       -      +
    278A  HIS*     3.2     4.6    +      -       -      +
    279A  THR*     2.8    30.5    +      -       -      +
----------------------------------------------------------
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Residues in contact with LEU 276 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    244A  LEU      4.0     8.5    -      -       -      +
    245A  CYS*     3.4    36.8    -      -       -      +
    248A  PRO*     3.6    35.0    -      -       +      -
    272A  LEU*     2.9    29.1    +      -       +      +
    273A  ALA*     3.7     7.6    -      -       -      +
    275A  VAL*     1.3    78.6    -      -       -      +
    277A  ALA*     1.3    59.3    +      -       -      +
    279A  THR*     3.5    20.9    +      -       +      -
    280A  ASN      3.7     0.9    +      -       -      -
----------------------------------------------------------
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Residues in contact with ALA 277 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    245A  CYS*     3.5    13.2    +      -       -      +
    246A  TRP*     3.8    46.5    -      -       +      +
    249A  LEU*     4.3     7.9    -      -       +      -
    273A  ALA      3.4     7.9    +      -       -      +
    274A  ILE      3.2     9.3    +      -       -      +
    275A  VAL      3.1     0.6    -      -       -      -
    276A  LEU*     1.3    77.7    -      -       -      +
    278A  HIS*     1.3    67.8    +      -       +      +
    279A  THR      3.1     1.8    -      -       -      -
    280A  ASN*     3.3    19.2    +      -       -      +
    281A  SER*     4.4     1.4    +      -       -      -
----------------------------------------------------------
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Residues in contact with HIS 278 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
      9A  TYR*     5.0     0.2    +      -       -      -
     13A  GLU*     3.6    27.7    +      -       -      +
     16A  ILE*     3.4    16.3    -      -       +      +
     55A  VAL*     4.2    13.5    -      -       +      +
     59A  ALA*     4.7     8.5    -      -       -      +
     60A  ILE*     4.1    27.1    +      -       +      +
     63A  ALA*     3.8    24.5    -      -       +      +
     84A  VAL*     4.8    19.0    -      -       +      +
    246A  TRP*     6.1     0.8    -      -       -      -
    274A  ILE*     2.9    41.7    +      -       +      +
    275A  VAL      3.2     5.7    +      -       -      +
    277A  ALA*     1.3    78.9    -      -       +      +
    279A  THR*     1.3    59.1    +      -       -      +
    281A  SER*     2.8    25.4    +      -       -      -
    330A  CFF      4.9     3.8    -      -       -      -
----------------------------------------------------------
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Residues in contact with THR 279 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     16A  ILE*     3.5    20.7    -      -       +      +
    245A  CYS*     5.5     2.7    -      -       -      -
    275A  VAL*     2.8    22.1    +      -       -      +
    276A  LEU*     3.6    20.5    -      -       +      +
    277A  ALA      3.1     0.6    -      -       -      -
    278A  HIS*     1.3    76.1    -      -       -      +
    280A  ASN*     1.3    64.0    +      -       -      +
    281A  SER      3.1     2.7    -      -       -      -
    282A  VAL*     2.9    22.1    +      -       +      +
    283A  VAL*     3.5    17.9    +      -       +      +
----------------------------------------------------------
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Residues in contact with ASN 280 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     52A  ASP*     4.6     2.2    -      -       -      -
    238A  ILE      4.9     2.0    +      -       -      -
    241A  LEU*     4.0    12.6    +      -       -      +
    242A  PHE*     2.9    49.7    -      -       -      +
    245A  CYS*     4.1    13.4    -      -       +      -
    246A  TRP*     3.2    13.2    +      -       -      +
    276A  LEU      3.7     2.6    +      -       -      -
    277A  ALA      3.3    14.5    +      -       -      +
    278A  HIS      3.2     0.2    -      -       -      -
    279A  THR*     1.3    79.6    -      -       -      +
    281A  SER*     1.3    57.2    +      -       -      +
    282A  VAL      3.1     0.2    -      -       -      -
    283A  VAL*     3.1    31.0    -      -       -      +
    284A  ASN*     3.8    13.2    +      -       -      +
----------------------------------------------------------
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Residues in contact with SER 281 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     20A  ALA*     3.6    15.7    -      -       -      +
     24A  ASN*     2.9    26.7    +      -       -      +
     52A  ASP*     3.4    45.2    -      -       -      +
     55A  VAL*     3.7    15.2    -      -       -      +
    277A  ALA      4.4     0.8    +      -       -      -
    278A  HIS      2.8    23.1    +      -       -      -
    280A  ASN*     1.3    78.4    -      -       -      +
    282A  VAL*     1.3    59.6    +      -       -      +
    284A  ASN*     4.5     0.6    +      -       -      -
    285A  PRO*     3.7     6.6    -      -       -      +
----------------------------------------------------------
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Residues in contact with VAL 282 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     16A  ILE*     3.8    27.8    -      -       +      +
     19A  LEU*     3.9    24.7    -      -       +      -
     20A  ALA*     3.6    30.7    -      -       +      +
    279A  THR*     2.9    15.8    +      -       +      +
    281A  SER*     1.3    78.1    -      -       -      +
    283A  VAL*     1.3    62.4    +      -       +      +
    284A  ASN      3.2     2.9    -      -       -      -
    285A  PRO*     3.0    18.6    -      -       +      +
    286A  PHE*     3.1    31.6    -      -       +      -
----------------------------------------------------------
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Residues in contact with VAL 283 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    238A  ILE      6.0     0.2    -      -       -      +
    241A  LEU*     4.1    30.3    -      -       +      -
    245A  CYS*     5.6     5.2    -      -       -      -
    279A  THR*     3.7    24.5    -      -       +      +
    280A  ASN*     3.1    31.6    -      -       -      +
    282A  VAL*     1.3    78.2    -      -       +      +
    284A  ASN*     1.3    67.5    +      -       -      +
    286A  PHE*     3.3     9.1    +      -       -      +
    287A  ILE*     2.9    29.8    +      -       -      +
----------------------------------------------------------
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Residues in contact with ASN 284 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     24A  ASN*     4.3     6.1    +      -       -      +
     48A  LEU*     3.3    29.2    -      -       +      +
     52A  ASP*     2.8    29.1    +      -       -      -
    238A  ILE*     3.6    18.0    -      -       -      +
    280A  ASN*     3.8    12.3    +      -       -      +
    281A  SER      4.5     1.2    +      -       -      +
    283A  VAL*     1.3    86.8    -      -       -      +
    285A  PRO*     1.3    73.8    -      -       +      +
    287A  ILE*     2.9    20.7    +      -       -      +
    288A  TYR*     2.8    33.1    -      -       +      +
----------------------------------------------------------
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Residues in contact with PRO 285 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     19A  LEU      5.2     1.3    -      -       -      +
     23A  GLY*     3.4    44.9    -      -       -      +
     24A  ASN*     3.5    13.7    -      -       -      +
     26A  LEU*     6.4     0.9    -      -       +      -
     27A  VAL*     4.0     6.7    -      -       +      -
    281A  SER      3.7     7.0    -      -       -      +
    282A  VAL*     3.0    19.7    -      -       -      +
    284A  ASN*     1.3    96.4    -      -       +      +
    286A  PHE*     1.3    65.5    +      -       +      +
    288A  TYR*     3.7    11.5    +      -       +      +
    289A  ALA*     3.5    20.3    +      -       -      +
    299A  PHE*     4.5     6.1    -      -       -      -
----------------------------------------------------------
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Residues in contact with PHE 286 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     19A  LEU*     4.9    15.7    -      -       +      -
     23A  GLY*     5.9     2.5    -      -       -      -
    282A  VAL*     3.1    43.7    -      -       +      -
    283A  VAL*     3.3     8.9    +      -       -      +
    284A  ASN      3.1     0.6    -      -       -      -
    285A  PRO*     1.3    81.3    -      -       +      +
    287A  ILE*     1.3    63.5    +      -       -      +
    288A  TYR      3.2     0.7    -      -       -      -
    289A  ALA*     3.6     8.1    +      -       +      +
    290A  TYR*     3.3    23.2    +      -       -      +
----------------------------------------------------------
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Residues in contact with ILE 287 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    234A  SER      4.3     2.2    -      -       -      +
    237A  ILE*     3.5    35.0    -      -       +      -
    238A  ILE*     3.7    36.8    -      -       +      +
    241A  LEU*     4.2    12.3    -      -       +      -
    283A  VAL      2.9    10.8    +      -       -      +
    284A  ASN*     2.9    32.1    +      -       -      +
    286A  PHE*     1.3    77.3    -      -       -      +
    288A  TYR*     1.3    67.6    +      -       +      +
    290A  TYR*     4.0     4.7    -      -       +      +
    291A  ARG*     3.1    43.9    +      -       +      +
----------------------------------------------------------
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Residues in contact with TYR 288 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     24A  ASN*     5.5     1.6    -      -       -      -
     27A  VAL*     4.3    17.0    -      -       +      -
     45A  VAL*     3.4    32.7    -      -       +      +
     48A  LEU*     3.3    27.5    -      -       +      +
     98A  ILE*     5.4     0.3    -      -       -      +
    234A  SER*     6.5     0.4    -      -       -      -
    238A  ILE*     3.5    29.1    -      -       +      +
    284A  ASN*     2.8    38.5    +      -       +      +
    285A  PRO*     3.9    10.1    -      -       +      +
    286A  PHE      3.2     0.2    -      -       -      -
    287A  ILE*     1.3    79.6    -      -       +      +
    289A  ALA*     1.3    59.6    +      -       -      +
    290A  TYR      3.1     1.8    -      -       -      -
    291A  ARG*     6.3     0.2    -      -       +      -
    292A  ILE*     2.9    56.8    +      -       +      +
    295A  PHE*     3.5    28.1    -      +       +      +
    299A  PHE*     4.6     2.0    -      -       +      -
----------------------------------------------------------
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Residues in contact with ALA 289 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    285A  PRO      3.5    15.3    +      -       -      +
    286A  PHE*     3.6     9.2    +      -       +      +
    287A  ILE      3.5     0.2    -      -       -      -
    288A  TYR*     1.3    79.1    -      -       -      +
    290A  TYR*     1.3    57.2    +      -       -      +
    292A  ILE      4.2     0.2    -      -       -      -
    296A  ARG*     2.9    46.4    +      -       +      +
    299A  PHE*     4.1    16.9    -      -       +      -
----------------------------------------------------------
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Residues in contact with TYR 290 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    286A  PHE      3.3    16.0    +      -       -      +
    287A  ILE*     4.3     4.0    -      -       +      +
    288A  TYR      3.1     0.6    -      -       -      -
    289A  ALA*     1.3    80.9    -      -       -      +
    291A  ARG*     1.3    92.2    +      -       +      +
    292A  ILE      3.5     2.5    +      -       -      -
    293A  ARG*     4.9     3.1    +      -       -      +
    296A  ARG*     5.0     9.9    +      -       -      +
----------------------------------------------------------
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Residues in contact with ARG 291 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    230A  HIS*     2.9    61.1    +      -       -      -
    233A  LYS*     3.5    35.2    -      -       -      +
    234A  SER*     2.9    40.6    +      -       -      +
    237A  ILE*     3.8    24.9    -      -       +      +
    287A  ILE*     3.1    33.3    +      -       +      +
    288A  TYR*     6.3     0.2    -      -       +      -
    290A  TYR*     1.3   102.0    -      -       +      +
    292A  ILE*     1.3    62.9    +      -       +      +
    293A  ARG*     3.6     6.6    +      -       -      +
----------------------------------------------------------
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Residues in contact with ILE 292 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     37A  LEU*     5.1     1.1    -      -       +      -
     42A  ASN*     5.9     1.3    -      -       -      +
    230A  HIS*     5.0     5.2    -      -       +      -
    231A  ALA*     6.3     4.5    -      -       +      -
    234A  SER*     4.8    11.9    -      -       -      +
    288A  TYR*     2.9    39.6    +      -       +      +
    289A  ALA      4.1     0.5    -      -       -      +
    290A  TYR      4.6     1.3    -      -       -      -
    291A  ARG*     1.3    81.9    -      -       +      +
    293A  ARG*     1.3    61.1    +      -       -      +
    294A  GLU*     3.3    22.7    +      -       +      +
    295A  PHE*     3.3    46.7    +      -       +      +
    296A  ARG*     3.4     9.9    +      -       -      +
----------------------------------------------------------
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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