Contacts of the helix formed by residues 338 - 362 (chain C) in PDB entry 1R5K


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 SER 338 (chain C).
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    338A  SER*     5.4     6.7    +      -       -      -
    341A  SER*     4.8     4.0    -      -       -      -
    337C  PHE*     1.3    86.3    -      -       -      +
    339C  GLU*     1.3    59.8    +      -       -      +
    340C  ALA*     3.4     6.4    +      -       -      +
    341C  SER*     3.3    21.3    +      -       -      -
    342C  MET*     2.8    32.2    +      -       -      +
    417C  CYS*     4.1    10.0    -      -       -      -
----------------------------------------------------------
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Residues in contact with GLU 339 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    338C  SER*     1.3    74.6    +      -       -      +
    340C  ALA*     1.3    64.3    +      -       -      +
    342C  MET*     3.7     1.7    -      -       -      +
    343C  MET*     3.0    28.9    +      -       +      +
    417C  CYS      3.4    16.5    +      -       -      +
    418C  VAL*     3.4    26.8    -      -       +      +
    419C  GLU*     3.4    30.9    +      -       -      +
    528C  MET*     4.7    10.8    -      -       -      +
----------------------------------------------------------
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Residues in contact with ALA 340 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    331A  TYR*     5.7    11.6    -      -       +      -
    341A  SER*     3.7    27.4    -      -       -      +
    344A  GLY*     5.7     1.0    -      -       -      -
    345A  LEU*     6.1     4.5    -      -       +      -
    338C  SER*     3.4     4.4    +      -       -      +
    339C  GLU*     1.3    79.7    -      -       -      +
    341C  SER*     1.3    57.7    +      -       -      +
    343C  MET*     3.4     5.8    +      -       -      +
    344C  GLY*     2.9    26.3    +      -       -      -
----------------------------------------------------------
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Residues in contact with SER 341 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    338A  SER*     4.8     4.2    +      -       -      -
    340A  ALA*     3.2    27.5    -      -       -      +
    341A  SER*     4.0    16.4    -      -       -      +
    337C  PHE*     4.4    14.4    -      -       -      -
    338C  SER*     3.3    26.9    +      -       -      -
    340C  ALA*     1.3    80.0    -      -       -      +
    342C  MET*     1.3    61.9    +      -       -      +
    344C  GLY*     3.3     1.4    +      -       -      -
    345C  LEU*     3.2    24.8    +      -       -      +
----------------------------------------------------------
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Residues in contact with MET 342 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    337C  PHE*     4.1    23.7    -      -       +      -
    338C  SER      2.8    21.1    +      -       -      +
    339C  GLU      3.7     4.3    -      -       -      +
    341C  SER*     1.3    71.4    -      -       -      +
    343C  MET*     1.3    63.6    +      -       -      +
    344C  GLY      3.4     0.3    +      -       -      -
    345C  LEU*     3.4    18.4    +      -       +      +
    346C  LEU*     3.1    42.1    +      -       +      +
    410C  LEU*     3.3    38.1    -      -       +      -
    414C  GLN*     4.5    11.2    -      -       -      +
    417C  CYS*     4.6     6.7    -      -       +      -
    418C  VAL*     3.7    10.8    -      -       +      -
    421C  MET*     3.6    27.4    -      -       +      -
----------------------------------------------------------
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Residues in contact with MET 343 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    331A  TYR*     3.4    36.3    -      -       +      +
    339C  GLU*     3.0    23.3    +      -       +      +
    340C  ALA*     3.9     4.5    -      -       -      +
    342C  MET*     1.3    72.6    -      -       -      +
    344C  GLY*     1.3    61.1    +      -       -      +
    346C  LEU*     3.9     5.8    -      -       +      +
    347C  THR*     2.7    39.2    +      -       -      +
    418C  VAL*     4.2    19.7    -      -       +      -
    421C  MET*     4.6     2.5    -      -       -      +
    525C  LEU*     4.1     8.1    -      -       +      -
    528C  MET*     4.0    26.0    -      -       -      +
    602C  GW5      3.8    49.6    -      -       +      -
----------------------------------------------------------
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Residues in contact with GLY 344 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    331A  TYR*     5.5     2.4    -      -       -      -
    340A  ALA      5.3     2.2    -      -       -      -
    344A  GLY*     4.4    22.6    -      -       -      -
    340C  ALA      2.9    16.3    +      -       -      -
    341C  SER*     3.7     2.7    -      -       -      -
    342C  MET      3.2     0.4    -      -       -      -
    343C  MET*     1.3    74.4    -      -       -      +
    345C  LEU*     1.3    67.6    +      -       -      +
    347C  THR*     4.0     2.5    -      -       -      -
    348C  ASN*     3.1    24.5    +      -       -      +
----------------------------------------------------------
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Residues in contact with LEU 345 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    340A  ALA*     6.3     4.3    -      -       +      -
    329C  SER*     3.8    10.0    +      -       -      +
    330C  GLU*     3.4    34.5    -      -       +      +
    331C  TYR      4.9     1.1    -      -       -      +
    332C  ASP*     3.9    10.1    -      -       +      +
    337C  PHE*     4.1    20.4    -      -       +      -
    341C  SER*     3.2    14.0    +      -       -      +
    342C  MET*     3.5    14.4    -      -       +      +
    344C  GLY*     1.3    76.4    -      -       -      +
    346C  LEU*     1.3    66.6    +      -       +      +
    348C  ASN*     3.3     4.6    +      -       -      +
    349C  LEU*     3.2    21.1    +      -       -      +
    408C  LEU*     3.5    39.7    -      -       +      -
----------------------------------------------------------
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Residues in contact with LEU 346 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    342C  MET*     3.1    42.1    +      -       +      +
    343C  MET*     4.4     5.4    -      -       -      +
    345C  LEU*     1.3    80.0    -      -       -      +
    347C  THR*     1.3    57.1    +      -       -      +
    349C  LEU*     3.4     5.4    +      -       +      +
    350C  ALA*     2.9    29.8    +      -       -      +
    404C  PHE*     3.7    41.7    -      -       +      -
    408C  LEU*     4.3     9.9    -      -       +      -
    410C  LEU*     4.3     1.6    -      -       +      -
    421C  MET*     4.1    26.9    -      -       +      -
    425C  PHE*     4.9     0.4    -      -       +      -
    602C  GW5      3.6    37.7    -      -       +      -
----------------------------------------------------------
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Residues in contact with THR 347 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    330A  GLU*     4.4     4.3    -      -       -      +
    331A  TYR*     4.0    14.5    +      -       +      -
    348A  ASN*     3.8    16.8    -      -       +      +
    343C  MET*     2.7    26.2    +      -       -      +
    344C  GLY*     4.0     3.1    -      -       -      -
    346C  LEU*     1.3    75.0    -      -       -      +
    348C  ASN*     1.3    60.7    +      -       -      +
    350C  ALA*     3.4     0.5    +      -       -      +
    351C  ASP*     2.9    48.3    +      -       -      +
    602C  GW5      3.2    47.9    -      -       -      +
----------------------------------------------------------
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Residues in contact with ASN 348 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    347A  THR*     4.3    23.0    -      -       +      +
    351A  ASP*     4.4     9.5    +      -       -      -
    533A  VAL*     5.7     0.7    -      -       -      +
    536A  LEU*     4.9     3.4    -      -       -      +
    600A  GW5      5.0     2.8    +      -       -      -
    330C  GLU*     4.4    18.4    +      -       -      +
    344C  GLY      3.1    17.8    +      -       -      +
    345C  LEU*     3.5     5.2    -      -       -      +
    347C  THR*     1.3    77.7    -      -       -      +
    349C  LEU*     1.3    57.4    +      -       -      +
    351C  ASP*     3.8     4.9    -      -       -      +
    352C  ARG*     3.0    56.5    +      -       -      +
----------------------------------------------------------
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Residues in contact with LEU 349 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    327C  LEU*     4.3    15.7    -      -       +      +
    328C  TYR      3.4    31.4    -      -       -      +
    329C  SER*     4.3     5.4    -      -       -      -
    345C  LEU      3.2    13.0    +      -       -      +
    346C  LEU*     3.7     5.4    -      -       +      +
    348C  ASN*     1.3    76.7    -      -       -      +
    350C  ALA*     1.3    61.4    +      -       -      +
    352C  ARG*     3.4    13.1    +      -       -      +
    353C  GLU*     2.9    43.2    +      -       -      +
    404C  PHE*     3.6    48.2    -      -       +      +
    405C  ALA*     4.7     1.3    -      -       +      -
    408C  LEU*     4.5    11.0    -      -       +      -
    602C  GW5      4.5     4.0    -      -       +      -
----------------------------------------------------------
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Residues in contact with ALA 350 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    346C  LEU      2.9    12.7    +      -       -      +
    347C  THR      3.8     2.7    -      -       -      +
    349C  LEU*     1.3    78.4    -      -       -      +
    351C  ASP*     1.3    57.1    +      -       -      +
    353C  GLU*     3.2     5.5    +      -       -      +
    354C  LEU*     2.8    31.4    +      -       -      +
    383C  TRP*     5.0     1.6    -      -       +      -
    387C  LEU*     3.8    17.9    -      -       +      +
    602C  GW5      3.1    51.3    -      -       +      -
----------------------------------------------------------
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Residues in contact with ASP 351 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    348A  ASN*     3.7    10.9    -      -       -      +
    351A  ASP*     5.0     4.0    -      -       -      +
    536A  LEU*     3.4    21.8    -      -       +      +
    347C  THR*     2.9    38.7    +      -       -      +
    348C  ASN*     3.8     5.4    +      -       -      +
    350C  ALA*     1.3    76.9    -      -       -      +
    352C  ARG*     1.3    61.7    +      -       -      +
    354C  LEU*     3.3    11.3    +      -       -      +
    355C  VAL*     3.2    27.2    +      -       -      +
    536C  LEU*     3.5    20.7    -      -       +      +
    537C  TYR      4.6     1.4    +      -       -      -
    540C  LEU*     4.8     0.9    -      -       -      +
    602C  GW5      2.9    27.5    -      -       -      +
----------------------------------------------------------
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Residues in contact with ARG 352 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    533A  VAL*     3.3    22.3    -      -       -      +
    534A  VAL      3.5    13.4    +      -       -      -
    535A  PRO*     4.3     2.0    -      -       -      -
    536A  LEU*     3.8    31.4    -      -       +      +
    539A  LEU*     3.7    20.3    -      -       +      +
    327C  LEU*     3.8    19.3    -      -       +      +
    328C  TYR      2.3    39.8    +      -       -      +
    329C  SER*     4.7     2.4    -      -       -      +
    330C  GLU*     4.7     2.6    +      -       -      -
    348C  ASN*     3.0    54.5    +      -       -      +
    349C  LEU*     3.8    17.3    -      -       -      +
    351C  ASP*     1.3    72.3    -      -       -      +
    353C  GLU*     1.3    67.1    +      -       -      +
    355C  VAL*     3.3    11.9    +      -       -      +
    356C  HIS*     3.3    17.8    +      -       -      -
----------------------------------------------------------
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Residues in contact with GLU 353 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    325C  PRO      5.7     0.2    -      -       -      +
    327C  LEU*     3.7    33.9    +      -       +      +
    349C  LEU*     2.9    35.0    +      -       -      +
    350C  ALA*     3.3     5.6    -      -       -      +
    352C  ARG*     1.3    77.3    -      -       -      +
    354C  LEU*     1.3    56.8    +      -       -      +
    356C  HIS*     3.0     8.8    +      -       +      +
    357C  MET*     2.9    28.0    +      -       +      +
    387C  LEU*     3.6    21.9    -      -       +      +
    394C  ARG*     4.4    20.4    +      -       -      +
    404C  PHE      5.1     2.6    -      -       -      +
    602C  GW5      4.1    17.5    -      -       -      -
----------------------------------------------------------
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Residues in contact with LEU 354 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    350C  ALA      2.8    19.8    +      -       -      +
    351C  ASP*     3.5    13.7    -      -       -      +
    352C  ARG      3.2     0.4    -      -       -      -
    353C  GLU*     1.3    73.4    -      -       -      +
    355C  VAL*     1.3    62.0    +      -       -      +
    357C  MET*     3.0    31.5    +      -       +      +
    358C  ILE*     3.2    14.1    +      -       +      +
    379C  LEU*     5.7     2.9    -      -       +      -
    383C  TRP*     3.8    38.4    -      -       +      -
    387C  LEU*     4.6     0.9    -      -       +      +
    536C  LEU*     5.3     0.4    -      -       +      -
    537C  TYR*     3.5    41.3    -      -       +      +
    540C  LEU*     4.5    17.5    -      -       +      -
    541C  LEU*     5.1    13.2    -      -       +      -
----------------------------------------------------------
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Residues in contact with VAL 355 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    536A  LEU*     4.7    15.0    -      -       +      -
    539A  LEU*     3.8    39.5    -      -       +      +
    540A  LEU*     4.8     6.1    -      -       +      -
    543A  MET*     4.2    22.2    -      -       +      +
    351C  ASP      3.2    15.1    +      -       -      +
    352C  ARG*     3.7     6.7    -      -       -      +
    353C  GLU      3.3     0.2    -      -       -      -
    354C  LEU*     1.3    77.6    -      -       -      +
    356C  HIS*     1.3    61.4    +      -       -      +
    357C  MET      3.5     0.3    +      -       -      -
    358C  ILE*     3.6    20.6    +      -       -      +
    359C  ASN*     4.0     6.1    +      -       -      +
    540C  LEU*     3.6    26.2    -      -       +      -
----------------------------------------------------------
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Residues in contact with HIS 356 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    534A  VAL*     5.9     1.8    -      -       +      +
    539A  LEU*     3.6    33.5    -      -       +      +
    324C  PRO*     4.2    19.7    -      -       +      +
    325C  PRO*     3.9    28.3    -      -       +      +
    327C  LEU*     3.5    33.4    -      -       +      +
    352C  ARG      3.3    19.4    +      -       -      -
    353C  GLU*     3.0     9.7    +      -       +      +
    355C  VAL*     1.3    77.7    -      -       +      +
    357C  MET*     1.3    64.1    +      -       -      +
    358C  ILE      3.3     0.2    -      -       -      -
    359C  ASN*     3.3     8.0    +      -       -      +
    360C  TRP*     3.1    22.1    +      -       -      +
----------------------------------------------------------
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Residues in contact with MET 357 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    324C  PRO*     6.1     1.1    -      -       -      -
    353C  GLU      2.9     9.0    +      -       -      +
    354C  LEU*     3.0    18.3    +      -       +      +
    356C  HIS*     1.3    75.3    -      -       -      +
    358C  ILE*     1.3    66.4    +      -       -      +
    360C  TRP*     3.4    25.7    -      -       +      -
    361C  ALA*     2.8    23.3    +      -       -      +
    379C  LEU*     4.1    16.2    -      -       +      -
    383C  TRP*     3.5    39.9    -      -       +      +
    386C  ILE*     3.7    22.2    -      -       +      -
    387C  LEU*     3.4    33.4    -      -       +      -
    449C  LYS*     5.8     0.7    -      -       -      +
----------------------------------------------------------
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Residues in contact with ILE 358 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    543A  MET*     4.0    27.4    -      -       +      -
    354C  LEU*     3.2    21.4    +      -       +      +
    355C  VAL*     3.8    12.1    -      -       -      +
    356C  HIS      3.3     0.6    -      -       -      -
    357C  MET*     1.3    80.5    -      -       -      +
    359C  ASN*     1.3    73.0    +      -       -      +
    361C  ALA*     3.2     6.4    +      -       -      +
    362C  LYS*     3.1    40.3    +      -       -      +
    367C  PHE*     5.5     0.2    -      -       -      -
    379C  LEU*     4.5    21.1    -      -       +      -
    540C  LEU*     4.8    20.2    -      -       +      +
    541C  LEU*     5.2     9.6    -      -       +      -
----------------------------------------------------------
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Residues in contact with ASN 359 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    543A  MET*     3.8    28.7    -      -       -      +
    355C  VAL      4.0     3.5    +      -       -      +
    356C  HIS*     3.3    11.5    +      -       -      +
    357C  MET      3.2     0.4    -      -       -      -
    358C  ILE*     1.3    86.5    -      -       -      +
    360C  TRP*     1.3    65.7    +      -       -      +
    362C  LYS*     3.7    21.0    +      -       -      +
    363C  ARG*     3.2    24.4    -      -       -      +
----------------------------------------------------------
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Residues in contact with TRP 360 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    319C  LEU*     5.2     2.4    +      -       -      +
    322C  ALA*     3.5    37.6    -      -       +      +
    323C  GLU*     4.1     3.4    +      -       -      -
    324C  PRO*     4.1    14.1    -      -       +      -
    356C  HIS      3.1    13.8    +      -       -      +
    357C  MET*     3.4    28.7    -      -       +      +
    359C  ASN*     1.3    78.4    -      -       -      +
    361C  ALA*     1.3    68.1    +      -       +      +
    363C  ARG*     2.8    28.3    +      -       -      +
    364C  VAL*     3.4    25.9    +      -       +      +
    386C  ILE*     3.7    25.1    -      -       +      -
    446C  VAL*     5.6     0.6    -      -       -      +
    449C  LYS*     3.3    64.4    -      -       +      +
    450C  SER*     4.2     6.4    +      -       -      -
    453C  LEU*     3.8    24.7    -      -       +      -
----------------------------------------------------------
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Residues in contact with ALA 361 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    357C  MET      2.8    17.5    +      -       -      +
    358C  ILE*     3.2     5.4    +      -       -      +
    360C  TRP*     1.3    91.3    -      -       +      +
    362C  LYS*     1.3    62.5    +      -       -      +
    364C  VAL*     3.0    14.6    +      -       -      +
    367C  PHE*     3.3    37.3    -      -       +      +
    379C  LEU*     3.9    15.3    -      -       +      -
    453C  LEU*     3.9    15.0    -      -       +      -
----------------------------------------------------------
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Residues in contact with LYS 362 (chain C). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    358C  ILE*     3.1    32.5    +      -       -      +
    359C  ASN*     3.7    22.2    -      -       -      +
    361C  ALA*     1.3    77.8    -      -       -      +
    363C  ARG*     1.3    61.0    +      -       +      +
    364C  VAL      3.8     3.4    +      -       -      +
    367C  PHE*     4.0    11.0    -      -       +      -
    368C  VAL*     4.2    30.8    -      -       +      +
    372C  LEU*     5.8     5.1    -      -       -      +
    375C  GLN*     4.2    16.0    +      -       -      +
----------------------------------------------------------
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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