Contacts of the helix formed by residues 422 - 448 (chain E) in PDB entry 1MKD


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 422 (chain E).
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    199E  TRP*     4.9     3.4    -      -       +      -
    200E  GLY*     3.8    23.8    -      -       -      +
    420E  THR      4.8     0.2    -      -       -      +
    421E  LYS*     1.3    88.0    -      -       +      +
    423E  LEU*     1.3    68.6    +      -       -      +
    424E  GLN*     3.2     5.6    -      -       +      +
    425E  LEU*     2.8    31.9    +      -       +      +
    426E  TYR      3.1     9.4    +      -       -      -
    495E  THR*     4.6     6.7    -      -       +      -
    509L  GLN*     6.3     3.1    -      -       +      -
----------------------------------------------------------
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Residues in contact with LEU 423 (chain E). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    421E  LYS      3.3     2.6    +      -       -      -
    422E  PRO*     1.3    71.1    -      -       -      +
    424E  GLN*     1.3    62.6    +      -       -      +
    426E  TYR*     4.2    13.5    -      -       +      -
    427E  ARG*     2.9    51.3    +      -       +      +
    495E  THR*     5.4     0.4    -      -       -      +
    499E  ASN*     3.5    31.2    +      -       +      +
    502E  TRP*     3.6    55.0    -      -       +      +
    503E  TYR*     4.6     0.9    -      -       +      -
    505L  SER*     4.3    19.3    -      -       -      +
    506L  THR*     4.7     4.5    -      -       -      -
----------------------------------------------------------
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Residues in contact with GLN 424 (chain E). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    202E  HIS*     3.1    34.7    +      -       -      -
    205E  ARG*     4.5     3.9    +      -       -      +
    422E  PRO*     3.0     5.2    +      -       +      +
    423E  LEU*     1.3    78.6    -      -       -      +
    425E  LEU*     1.3    62.7    +      -       +      +
    427E  ARG*     3.9     8.0    +      -       -      +
    428E  GLN*     3.2    37.2    +      -       +      +
    508L  PRO*     4.3    22.4    -      -       +      +
    509L  GLN      4.7     3.7    +      -       -      +
    510L  SER*     3.7    22.0    +      -       -      -
----------------------------------------------------------
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Residues in contact with LEU 425 (chain E). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    200E  GLY*     3.6    26.7    -      -       -      +
    201E  LEU      3.9    11.4    -      -       -      +
    202E  HIS*     4.0    28.9    -      -       +      +
    203E  VAL*     4.7     5.2    -      -       +      +
    204E  PHE*     3.8    26.5    -      -       +      -
    421E  LYS*     4.2    13.5    -      -       +      +
    422E  PRO*     2.8    31.8    +      -       +      +
    424E  GLN*     1.3    79.6    -      -       +      +
    426E  TYR*     1.3    66.3    +      -       -      +
    428E  GLN*     2.9    18.5    +      -       -      +
    429E  TRP*     3.1    23.1    +      -       +      +
----------------------------------------------------------
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Residues in contact with TYR 426 (chain E). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    418E  ASN*     3.4    19.4    +      -       +      +
    419E  PRO*     3.6    31.1    -      -       +      +
    421E  LYS      4.2     2.5    -      -       -      +
    422E  PRO      3.1     8.0    +      -       -      +
    423E  LEU*     3.7    12.1    -      -       +      +
    425E  LEU*     1.3    77.9    -      -       -      +
    427E  ARG*     1.3    62.8    +      -       -      +
    429E  TRP*     3.0     9.6    +      -       -      +
    430E  THR*     2.9    35.3    +      -       -      -
    466E  GLN*     2.7    30.0    +      -       -      +
    470E  ILE*     3.4    20.6    -      -       +      +
    499E  ASN*     3.7    28.9    -      -       +      -
    503E  TYR*     3.4    26.9    -      +       -      -
   3005E  ZAR      3.5    15.3    -      -       -      -
----------------------------------------------------------
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Residues in contact with ARG 427 (chain E). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    423E  LEU*     2.9    49.1    +      -       +      +
    424E  GLN*     4.1     6.7    -      -       -      +
    426E  TYR*     1.3    76.2    -      -       -      +
    428E  GLN*     1.3    62.3    +      -       +      +
    430E  THR*     3.3     2.3    +      -       -      -
    431E  ASP*     3.0    31.7    +      -       -      +
    502E  TRP*     3.2    29.5    -      -       +      -
    503E  TYR*     3.6    18.7    +      -       -      +
    427L  ARG*     5.2     8.7    -      -       -      +
    502L  TRP*     6.2     0.2    -      -       -      -
    506L  THR*     3.9    24.9    -      -       -      +
----------------------------------------------------------
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Residues in contact with GLN 428 (chain E). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    202E  HIS*     3.7    12.0    +      -       -      -
    204E  PHE*     3.3    40.0    -      -       +      +
    424E  GLN*     3.2    46.6    +      -       +      +
    425E  LEU*     2.9     9.6    +      -       -      +
    427E  ARG*     1.3    77.7    -      -       +      +
    429E  TRP*     1.3    63.0    +      -       -      +
    431E  ASP*     3.3    11.1    +      -       -      +
    432E  ARG*     3.1    30.3    +      -       -      +
----------------------------------------------------------
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Residues in contact with TRP 429 (chain E). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    203E  VAL*     4.0    12.0    -      -       +      +
    204E  PHE*     3.5    27.6    -      +       -      -
    255E  ALA      5.6     0.2    -      -       -      -
    256E  TYR*     3.6    29.2    -      +       -      -
    258E  ASN*     5.3     0.7    -      -       -      -
    260E  ILE*     3.8    15.0    -      -       +      -
    261E  HIS*     3.7    37.0    -      -       +      -
    264E  ASP*     3.5    30.3    +      -       +      -
    418E  ASN*     3.5    40.4    -      -       +      +
    421E  LYS*     5.4     4.1    -      -       +      +
    425E  LEU*     3.1    33.7    +      -       +      +
    426E  TYR*     3.0     7.5    +      -       -      +
    428E  GLN*     1.3    78.0    -      -       -      +
    430E  THR*     1.3    58.5    +      -       -      +
    432E  ARG*     3.0    12.8    +      -       -      +
    433E  ILE*     2.8    26.9    +      -       -      +
   3005E  ZAR      3.3    10.6    -      -       -      -
----------------------------------------------------------
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Residues in contact with THR 430 (chain E). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    426E  TYR*     2.9    32.2    +      -       -      -
    427E  ARG      3.6     4.5    -      -       -      -
    428E  GLN      3.3     0.2    -      -       -      -
    429E  TRP*     1.3    75.9    -      -       -      +
    431E  ASP*     1.3    65.0    +      -       -      +
    433E  ILE*     3.0     4.6    -      -       -      +
    434E  MET*     3.0    29.1    +      -       +      +
    462E  VAL*     3.8    21.1    -      -       +      -
    466E  GLN*     3.5    27.7    -      -       +      +
    503E  TYR*     3.2    27.3    +      -       -      +
   3005E  ZAR      3.3    10.7    -      -       -      -
----------------------------------------------------------
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Residues in contact with ASP 431 (chain E). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    427E  ARG*     3.0    22.8    +      -       -      +
    428E  GLN*     3.5    10.9    -      -       -      +
    429E  TRP      3.2     0.2    -      -       -      -
    430E  THR*     1.3    80.2    -      -       -      +
    432E  ARG*     1.3    59.1    +      -       +      +
    434E  MET*     3.8     4.6    -      -       -      +
    435E  GLU*     2.9    30.8    +      -       -      +
    462E  VAL*     5.7     3.1    -      -       -      +
    503E  TYR*     5.5     0.7    +      -       -      -
----------------------------------------------------------
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Residues in contact with ARG 432 (chain E). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    204E  PHE*     3.1    37.3    -      -       -      -
    255E  ALA*     2.8    49.1    +      -       +      +
    256E  TYR*     4.0     7.0    -      -       +      -
    258E  ASN*     4.0     9.1    -      -       -      +
    260E  ILE*     3.7    22.3    -      -       -      +
    428E  GLN*     3.1    20.0    +      -       -      +
    429E  TRP*     3.0    17.1    +      -       -      +
    431E  ASP*     1.3    75.0    -      -       +      +
    433E  ILE*     1.3    60.5    +      -       -      +
    435E  GLU*     3.1    10.9    +      -       -      +
    436E  GLU*     2.9    24.1    +      -       -      +
----------------------------------------------------------
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Residues in contact with ILE 433 (chain E). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    256E  TYR*     3.6    37.4    -      -       +      -
    257E  HIS*     3.9    12.8    -      -       +      -
    429E  TRP      2.8    12.4    +      -       -      +
    430E  THR*     3.0    17.7    -      -       -      +
    432E  ARG*     1.3    73.1    -      -       -      +
    434E  MET*     1.3    71.5    +      -       +      +
    436E  GLU*     3.2     3.2    +      -       +      +
    437E  PHE*     2.9    65.5    +      -       +      -
    466E  GLN*     4.6     1.1    -      -       -      +
   3005E  ZAR      3.6    47.1    -      -       +      +
----------------------------------------------------------
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Residues in contact with MET 434 (chain E). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    430E  THR*     3.0    19.8    +      -       +      +
    431E  ASP*     3.9     4.9    -      -       -      +
    433E  ILE*     1.3    86.7    -      -       +      +
    435E  GLU*     1.3    65.0    +      -       -      +
    437E  PHE*     3.8     6.2    -      -       -      +
    438E  PHE*     3.1    59.4    +      -       +      -
    454E  MET*     3.6    52.0    -      -       +      +
    460E  ALA*     4.2     6.7    -      -       +      -
    462E  VAL*     3.9    40.4    -      -       +      +
    465E  SER*     5.2     0.9    -      -       -      +
    466E  GLN*     4.7     4.9    -      -       -      -
----------------------------------------------------------
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Residues in contact with GLU 435 (chain E). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    255E  ALA*     3.7    20.2    -      -       +      +
    431E  ASP      2.9    19.0    +      -       -      +
    432E  ARG*     3.1    12.2    +      -       -      +
    434E  MET*     1.3    78.3    -      -       -      +
    436E  GLU*     1.3    51.0    +      -       -      +
    438E  PHE*     4.4     5.6    -      -       -      +
    439E  PRO*     2.5    34.1    -      -       +      +
----------------------------------------------------------
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Residues in contact with GLU 436 (chain E). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    254E  VAL*     3.2    15.4    -      -       +      +
    255E  ALA*     4.1     9.0    -      -       +      +
    256E  TYR*     2.8    31.3    +      -       -      +
    257E  HIS*     2.8    38.5    +      -       -      -
    301E  HIS*     4.1     0.7    -      -       -      -
    303E  GLY*     3.2    34.9    -      -       -      +
    432E  ARG      2.9    14.0    +      -       -      +
    433E  ILE*     3.6     6.7    -      -       -      +
    435E  GLU*     1.3    78.2    -      -       -      +
    437E  PHE*     1.3    70.4    +      -       +      +
    438E  PHE      3.3     0.4    -      -       -      -
    439E  PRO*     3.1    13.1    -      -       -      +
    440E  GLN*     3.5    11.6    +      -       -      +
----------------------------------------------------------
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Residues in contact with PHE 437 (chain E). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    257E  HIS*     5.3     5.2    -      +       -      -
    303E  GLY      6.1     0.7    -      -       -      -
    433E  ILE*     2.9    51.2    +      -       +      +
    434E  MET*     3.4    12.1    +      -       -      +
    436E  GLU*     1.3    81.8    -      -       +      +
    438E  PHE*     1.3    57.5    +      -       -      +
    440E  GLN*     3.1    12.3    +      -       -      +
    441E  GLY      2.9    22.0    +      -       -      -
    454E  MET*     3.7    48.5    -      -       +      +
    455E  CYS*     3.2    32.9    -      -       -      +
   3005E  ZAR      4.0    28.9    -      +       -      -
----------------------------------------------------------
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Residues in contact with PHE 438 (chain E). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    434E  MET*     3.1    38.0    +      -       +      -
    435E  GLU*     4.4     4.5    -      -       -      +
    437E  PHE*     1.3    74.1    -      -       -      +
    439E  PRO*     1.4    60.1    -      -       +      +
    441E  GLY*     2.9     2.6    +      -       -      -
    442E  ASP*     2.7    43.0    +      -       -      +
    454E  MET      3.4    18.8    -      -       -      -
    455E  CYS      3.5     9.2    -      -       -      +
    457E  LYS*     3.5    48.5    -      -       +      -
    460E  ALA*     3.6    27.8    -      -       +      -
    462E  VAL*     4.9     5.4    -      -       +      -
----------------------------------------------------------
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Residues in contact with PRO 439 (chain E). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    435E  GLU*     2.5    31.6    -      -       +      +
    436E  GLU*     3.1    11.9    -      -       -      +
    438E  PHE*     1.4    87.8    -      -       +      +
    440E  GLN*     1.3    55.4    +      -       -      +
    442E  ASP*     3.5    14.8    -      -       +      +
    443E  ARG*     2.8    35.4    +      -       +      +
----------------------------------------------------------
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Residues in contact with GLN 440 (chain E). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    303E  GLY      4.0     3.9    +      -       -      +
    304E  VAL*     3.2    17.3    -      -       +      -
    305E  SER*     2.9    45.7    +      -       -      -
    308E  PHE*     3.8    20.7    -      -       +      +
    436E  GLU      3.5     8.7    +      -       -      +
    437E  PHE*     3.1    16.3    +      -       -      +
    438E  PHE      3.0     0.4    -      -       -      -
    439E  PRO*     1.3    78.4    -      -       -      +
    441E  GLY*     1.3    60.4    +      -       -      +
    443E  ARG*     3.1     8.4    +      -       -      +
    444E  GLU*     2.8    52.6    +      -       -      +
    452E  SER*     3.8     9.1    +      -       -      -
    455E  CYS*     4.1    15.4    -      -       +      -
----------------------------------------------------------
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Residues in contact with GLY 441 (chain E). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    437E  PHE      2.9     7.9    +      -       -      -
    438E  PHE      2.9     3.8    +      -       -      -
    440E  GLN*     1.3    78.0    -      -       -      +
    442E  ASP*     1.3    56.9    +      -       -      +
    444E  GLU*     3.3    14.5    +      -       -      -
    445E  ARG*     2.9    28.1    +      -       -      +
    451E  ILE*     3.0    16.2    -      -       -      +
    455E  CYS*     3.2    25.7    -      -       -      +
----------------------------------------------------------
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Residues in contact with ASP 442 (chain E). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    438E  PHE*     2.7    21.6    +      -       -      +
    439E  PRO*     3.5    17.3    -      -       +      +
    441E  GLY*     1.3    70.8    -      -       -      +
    443E  ARG*     1.3    65.8    +      -       -      +
    445E  ARG*     2.9    39.1    +      -       -      +
    446E  GLU*     2.9    26.0    +      -       +      +
    457E  LYS*     3.0    37.0    +      -       -      +
----------------------------------------------------------
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Residues in contact with ARG 443 (chain E). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    302E  PRO      5.3     3.8    +      -       -      -
    304E  VAL*     3.8    18.6    -      -       -      +
    308E  PHE*     3.4    35.0    -      -       +      -
    439E  PRO*     2.8    26.1    +      -       +      +
    440E  GLN*     3.2    11.4    -      -       -      +
    442E  ASP*     1.3    76.6    -      -       -      +
    444E  GLU*     1.3    56.9    +      -       -      +
    446E  GLU*     3.4    18.8    +      -       -      +
    447E  ARG*     3.0    62.2    +      -       -      +
----------------------------------------------------------
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Residues in contact with GLU 444 (chain E). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    308E  PHE*     3.6    23.3    -      -       +      +
    311E  ASN*     5.7     1.4    +      -       -      -
    440E  GLN*     2.8    33.1    +      -       -      +
    441E  GLY*     3.6    14.6    +      -       -      +
    443E  ARG*     1.3    75.5    -      -       -      +
    445E  ARG*     1.3    62.4    +      -       -      +
    447E  ARG      3.4     0.5    +      -       -      -
    448E  GLY      3.0     3.1    +      -       -      -
    449E  MET*     2.8    56.2    +      -       +      +
    450E  GLU      4.1     5.6    -      -       -      +
    451E  ILE*     3.6     9.1    -      -       +      -
    452E  SER*     2.6    51.5    +      -       -      -
    455E  CYS*     4.2     0.3    -      -       -      +
----------------------------------------------------------
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Residues in contact with ARG 445 (chain E). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    441E  GLY      2.9    15.0    +      -       -      +
    442E  ASP*     2.9    39.8    +      -       -      +
    444E  GLU*     1.3    76.0    -      -       -      +
    446E  GLU*     1.3    63.0    +      -       +      +
    448E  GLY*     3.1    12.4    +      -       -      -
    449E  MET      4.6     1.6    -      -       -      -
    451E  ILE*     3.2    18.4    -      -       +      +
    456E  ASP*     3.0    29.1    +      -       -      +
    457E  LYS*     3.9    15.2    -      -       -      +
    458E  HIS*     3.8    27.2    +      -       -      -
----------------------------------------------------------
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Residues in contact with GLU 446 (chain E). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    442E  ASP*     2.9    28.6    +      -       +      +
    443E  ARG*     3.4    26.0    +      -       -      +
    445E  ARG*     1.3    74.5    -      -       +      +
    447E  ARG*     1.3    66.6    +      -       -      +
    448E  GLY*     2.9    11.0    +      -       -      -
----------------------------------------------------------
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Residues in contact with ARG 447 (chain E). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    308E  PHE*     4.0     8.8    -      -       +      -
    312E  THR*     4.1    17.2    -      -       +      +
    443E  ARG*     3.0    62.3    +      -       -      +
    444E  GLU      3.4     1.3    +      -       -      +
    446E  GLU*     1.3    84.6    +      -       -      +
    448E  GLY*     1.3    58.7    +      -       -      +
    449E  MET*     3.1    37.9    +      -       +      +
----------------------------------------------------------
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Residues in contact with GLY 448 (chain E). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    444E  GLU      3.0     2.6    +      -       -      -
    445E  ARG*     3.1    11.2    +      -       -      -
    446E  GLU      2.9     6.9    -      -       -      -
    447E  ARG*     1.3    79.6    -      -       -      +
    449E  MET*     1.3    64.9    +      -       -      +
    450E  GLU      4.1     0.3    +      -       -      -
----------------------------------------------------------
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A short description of the analytical approach
The contact analysis used in this page is based upon the approach developed in: Sobolev V., Wade R.C., Vriend G. and Edelman M. PROTEINS (1996) 25, 120-129. Contact legitimacy depends on the hydrophobic-hydrophilic properties of the contacting atoms. In order to define it, for each inter-atomic contact, eight atom classes have been introduced:


   I  Hydrophilic      - N and O that can donate and accept hydrogen bonds
                         (e.g., oxygen of hydroxyl group of Ser. or Thr)
  II  Acceptor         - N or O that can only accept a hydrogen bond
 III  Donor            - N that can only donate a hydrogen bond
  IV  Hydrophobic      - Cl, Br, I and all C atoms that are not in
                         aromatic rings and do not have a covalent bond to
                         a N or O atom
   V  Aromatic         - C in aromatic rings irrespective of any other 
                         bonds formed by the atom
  VI  Neutral          - C atoms that have a covalent bond to at least one
                         atom of class I or two or more atoms from class II
                         or III; atoms; S, F, P, and metal atoms in all cases
 VII  Neutral-donor    - C atoms that have a covalent bond with only one
                         atom of class III
VIII  Neutral-acceptor - C atoms that have a covalent bond with only 
                         one atom of class II
For each pair of contacts the state of legitimacy is shown below:

Legend:
+, legitimate
-, illegitimate
------------------------------------------------------------
  Atomic class           I  II  III   IV   V   VI  VII  VIII
------------------------------------------------------------
   I  (Hydrophilic)      +   +    +    -   +   +    +    +
  II  (Acceptor)         +   -    +    -   +   +    +    -
 III  (Donor)            +   +    -    -   +   +    -    +
  IV  (Hydrophobic)      -   -    -    +   +   +    +    +
   V  (Aromatic)         +   +    +    +   +   +    +    +
  VI  (Neutral)          +   +    +    +   +   +    +    +
 VII  (Neutral-donor)    +   +    -    +   +   +    -    +
VIII  (Neutral-acceptor) +   -    +    +   +   +    +    -
------------------------------------------------------------
Warning!
Atom classes for heterogroups are automatically assigned based on the atomic coordinates. However, in three cases (see below) the automatic assignment is currently ambiguous. In these cases, the user is advised to manually analyse the full list of contacts using LPC software.
1. Carbon atoms belonging to a 4-, 5- or 6-member ring are 
   considered "aromatic" (Class V) if the ring is approximately
   planar, and "hydrophobic" (Class IV) or "neutral" (Classes
   VI, VII, VIII) if the ring is non-planar.
2. The oxygen atom of a carbonyl or hydroxy group is considered
   "hydroxy" (Class I) if the CO bond is longer than 1.29 Å, and
   "carbonyl" (Class II) if shorter.
3. All nitrogen atoms are considered "hydrophilic" (Class I).

Please E-mail any questions and/or suggestions concerning this page to Vladimir.Sobolev@weizmann.ac.il