Contacts of the helix formed by residues 521 - 546 (chain D) in PDB entry 6T8B


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 MET 521 (chain D).
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    617C  GLN*     3.4    26.7    -      -       -      +
    618C  LYS*     5.7     2.7    -      -       -      +
    499D  PRO*     4.1     9.4    -      -       +      -
    520D  ASP*     1.3    76.9    -      -       -      +
    522D  LYS*     1.3    64.9    +      -       -      +
    523D  GLU      3.4     1.1    +      -       -      -
    524D  ALA*     3.6    13.3    +      -       -      +
    525D  ALA*     4.3     2.3    +      -       -      +
    599D  ASP*     3.3    27.4    -      -       +      +
    600D  MET*     3.5    33.0    -      -       -      +
    603D  ILE*     3.6    30.5    -      -       +      -
    604D  VAL*     3.8    20.6    -      -       +      +
----------------------------------------------------------
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Residues in contact with LYS 522 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    520D  ASP*     4.0     7.5    -      -       +      +
    521D  MET*     1.3    80.7    -      -       -      +
    523D  GLU*     1.3    59.9    +      -       -      +
    524D  ALA      3.6     0.2    +      -       -      -
    525D  ALA*     4.1     8.5    +      -       -      +
    526D  ASN*     3.1    22.8    +      -       -      +
    604D  VAL*     5.7     2.0    -      -       -      -
----------------------------------------------------------
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Residues in contact with GLU 523 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    515D  CYS*     6.1     0.2    -      -       -      +
    518D  VAL*     3.1    32.9    -      -       -      +
    520D  ASP*     3.3    20.8    +      -       -      +
    521D  MET      3.4     0.2    -      -       -      -
    522D  LYS*     1.3    78.0    -      -       +      +
    524D  ALA*     1.3    59.7    +      -       -      +
    525D  ALA      3.4     0.7    -      -       -      -
    526D  ASN*     3.2    14.8    +      -       +      +
    527D  ALA*     2.9    35.5    +      -       -      +
    720D  ILE*     5.0     0.7    -      -       -      +
    721D  LEU*     3.1    53.7    +      -       +      +
----------------------------------------------------------
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Residues in contact with ALA 524 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    497D  ILE*     3.8    24.5    -      -       +      +
    499D  PRO*     6.2     0.2    -      -       +      -
    518D  VAL*     4.0     9.0    -      -       -      -
    520D  ASP*     3.9    13.8    +      -       -      +
    521D  MET*     3.6    13.9    +      -       -      +
    522D  LYS      3.4     1.0    -      -       -      -
    523D  GLU*     1.3    78.0    -      -       -      +
    525D  ALA*     1.3    63.5    +      -       -      +
    527D  ALA*     3.3     3.5    +      -       -      +
    528D  LEU*     3.0    28.9    +      -       -      +
    600D  MET*     3.8    22.2    -      -       +      -
----------------------------------------------------------
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Residues in contact with ALA 525 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    521D  MET      4.3     3.9    +      -       -      +
    522D  LYS      4.1     8.3    +      -       -      +
    523D  GLU      3.4     0.2    -      -       -      -
    524D  ALA*     1.3    79.0    -      -       -      +
    526D  ASN*     1.3    56.4    +      -       -      +
    528D  LEU*     4.4     9.2    -      -       -      +
    529D  ARG*     2.9    56.7    +      -       -      +
    600D  MET*     5.8     0.2    -      -       -      +
    604D  VAL*     5.3     8.7    -      -       +      -
    607D  LYS*     5.0    13.2    -      -       +      -
    608D  VAL*     5.1    10.0    -      -       +      +
    611D  LEU*     3.5     7.4    -      -       +      +
----------------------------------------------------------
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Residues in contact with ASN 526 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    522D  LYS*     3.1    30.2    +      -       -      +
    523D  GLU*     3.2    23.7    +      -       +      +
    524D  ALA      3.1     0.8    -      -       -      -
    525D  ALA*     1.3    75.6    -      -       -      +
    527D  ALA*     1.3    59.8    +      -       -      +
    529D  ARG*     3.2    25.6    +      -       -      +
    530D  TRP*     2.9    26.5    +      -       -      +
    720D  ILE      4.0     7.8    -      -       -      +
    721D  LEU      5.0     6.7    +      -       -      +
----------------------------------------------------------
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Residues in contact with ALA 527 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    495D  ILE*     5.0     9.5    -      -       +      +
    497D  ILE*     4.3    16.6    -      -       +      -
    518D  VAL*     4.5     9.0    -      -       +      -
    523D  GLU*     2.9    30.6    +      -       -      +
    524D  ALA*     3.7     3.8    -      -       -      +
    526D  ASN*     1.3    75.8    -      -       -      +
    528D  LEU*     1.3    58.8    +      -       -      +
    530D  TRP*     3.3     8.2    +      -       -      +
    531D  SER*     2.9    25.8    +      -       -      -
    720D  ILE*     4.1    19.5    -      -       +      +
----------------------------------------------------------
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Residues in contact with LEU 528 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    497D  ILE*     4.3     9.0    -      -       +      -
    524D  ALA      3.0    22.9    +      -       -      +
    525D  ALA*     3.7     1.1    -      -       -      +
    527D  ALA*     1.3    75.0    -      -       -      +
    529D  ARG*     1.3    59.3    +      -       -      +
    531D  SER*     2.4    32.0    +      -       -      +
    532D  VAL*     2.9    18.2    +      -       -      +
    592D  VAL*     4.0    27.4    -      -       +      -
    594D  VAL*     5.3     1.8    -      -       +      -
    600D  MET*     3.9    16.2    -      -       +      -
    608D  VAL*     3.5    33.2    -      -       +      -
    611D  LEU*     3.6    20.2    -      -       +      -
    612D  ILE*     4.3    17.3    -      -       +      -
    615D  ILE*     5.1     4.9    -      -       +      -
    626D  LEU*     5.0     3.8    -      -       +      -
----------------------------------------------------------
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Residues in contact with ARG 529 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    525D  ALA*     2.9    48.8    +      -       -      +
    526D  ASN*     3.2    25.6    +      -       -      +
    528D  LEU*     1.3    75.4    -      -       -      +
    530D  TRP*     1.3    63.8    +      -       -      +
    532D  VAL*     3.2     8.8    +      -       -      +
    533D  ALA*     2.9    22.0    +      -       -      +
    607D  LYS*     4.0    37.2    -      -       -      +
    611D  LEU*     3.5    24.2    -      -       +      +
----------------------------------------------------------
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Residues in contact with TRP 530 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    495D  ILE*     4.0    22.2    -      -       +      -
    514D  LEU*     4.3    15.7    -      -       +      -
    526D  ASN      2.9     7.9    +      -       -      +
    527D  ALA      3.5     7.4    -      -       -      +
    529D  ARG*     1.3    78.1    -      -       -      +
    531D  SER*     1.3    62.3    +      -       -      +
    533D  ALA*     3.2    11.7    +      -       +      +
    534D  GLU*     2.9    59.2    +      -       +      +
    537D  ARG*     6.1     1.0    -      -       -      +
    590D  ILE*     4.6     5.4    -      -       +      -
    717D  ILE*     5.0     9.4    -      -       +      -
    719D  ASP*     4.0    27.9    +      -       -      +
    720D  ILE*     3.6    61.7    -      -       +      +
----------------------------------------------------------
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Residues in contact with SER 531 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    495D  ILE*     5.1     4.0    -      -       -      -
    527D  ALA      2.9    12.4    +      -       -      -
    528D  LEU*     2.4    37.2    +      -       -      +
    530D  TRP*     1.3    82.4    -      -       -      +
    532D  VAL*     1.3    58.0    +      -       -      +
    534D  GLU*     3.3     4.7    +      -       -      +
    535D  MET      2.9    24.1    +      -       -      -
    590D  ILE*     6.1     0.9    -      -       -      -
    592D  VAL*     4.7    18.8    -      -       -      -
    615D  ILE*     3.2    19.2    -      -       -      +
    624D  ILE*     3.4    18.5    -      -       -      +
----------------------------------------------------------
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Residues in contact with VAL 532 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    528D  LEU      2.9    22.0    +      -       -      +
    529D  ARG*     3.4    10.5    -      -       -      +
    531D  SER*     1.3    76.8    +      -       -      +
    533D  ALA*     1.3    57.0    +      -       -      +
    535D  MET*     3.2    15.7    +      -       +      +
    536D  GLU*     2.9    36.3    +      -       +      +
    611D  LEU*     4.4    15.3    -      -       +      +
    614D  ARG*     3.3    37.5    -      -       -      +
    615D  ILE*     3.5    26.9    -      -       +      +
----------------------------------------------------------
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Residues in contact with ALA 533 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    529D  ARG      2.9    12.5    +      -       -      +
    530D  TRP*     3.2    17.0    +      -       +      +
    532D  VAL*     1.3    77.1    -      -       -      +
    534D  GLU*     1.3    57.5    +      -       -      +
    536D  GLU*     3.2     9.3    +      -       -      +
    537D  ARG*     2.9    32.1    +      -       -      +
    540D  ARG*     5.0     0.3    +      -       -      -
----------------------------------------------------------
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Residues in contact with GLU 534 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    530D  TRP*     2.9    44.6    +      -       +      +
    531D  SER*     3.6     8.7    -      -       -      +
    533D  ALA*     1.3    73.6    -      -       -      +
    535D  MET*     1.3    60.6    +      -       -      +
    537D  ARG*     2.6    45.3    +      -       -      +
    538D  ARG*     2.8    59.5    +      -       -      +
    587D  LEU*     5.6     0.5    -      -       -      +
    590D  ILE*     3.8    25.1    -      -       +      -
    624D  ILE*     4.6     2.0    -      -       +      -
----------------------------------------------------------
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Residues in contact with MET 535 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    531D  SER      2.9     6.8    +      -       -      +
    532D  VAL*     3.3    21.5    -      -       +      +
    534D  GLU*     1.3    76.6    -      -       -      +
    536D  GLU*     1.3    78.9    +      -       -      +
    538D  ARG*     3.2     7.5    +      -       -      +
    539D  TYR*     2.9    52.0    +      -       +      -
    614D  ARG*     3.2    32.8    -      -       +      +
    615D  ILE*     4.3     3.6    -      -       -      +
    618D  LYS*     3.7    13.7    -      -       -      -
    619D  ALA*     3.6    33.4    -      -       +      -
    622D  ALA*     4.2     2.7    -      -       +      -
    624D  ILE*     3.5    23.2    -      -       +      +
----------------------------------------------------------
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Residues in contact with GLU 536 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    532D  VAL*     2.9    25.7    +      -       +      +
    533D  ALA*     3.2    10.1    +      -       -      +
    535D  MET*     1.3    89.6    -      -       -      +
    537D  ARG*     1.3    58.5    +      -       -      +
    539D  TYR*     3.2     8.7    +      -       -      +
    540D  ARG*     2.9    58.0    +      -       -      +
    614D  ARG*     4.0    14.9    +      -       -      +
    618D  LYS*     3.2    28.6    +      -       -      -
----------------------------------------------------------
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Residues in contact with ARG 537 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    530D  TRP*     6.1     1.1    -      -       -      +
    533D  ALA      2.9    14.4    +      -       -      +
    534D  GLU*     2.6    62.7    +      -       -      +
    536D  GLU*     1.3    76.7    -      -       -      +
    538D  ARG*     1.3    57.5    +      -       -      +
    540D  ARG*     3.7    16.3    -      -       -      +
    541D  LEU*     2.9    40.4    +      -       -      +
    587D  LEU*     5.3    10.3    -      -       -      +
----------------------------------------------------------
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Residues in contact with ARG 538 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    534D  GLU*     2.8    49.0    +      -       -      +
    535D  MET      3.5     4.9    -      -       -      +
    537D  ARG*     1.3    76.0    -      -       -      +
    539D  TYR*     1.3    62.3    +      -       -      +
    541D  LEU*     4.4     5.6    -      -       -      +
    542D  MET*     3.1    35.8    +      -       +      +
    550D  LEU*     3.6    11.9    -      -       -      +
    587D  LEU*     3.2    47.6    -      -       +      +
    588D  PRO*     3.7    18.4    +      -       -      +
    590D  ILE*     3.6    23.7    -      -       -      +
    622D  ALA*     3.1    38.1    -      -       +      +
    623D  GLY*     4.0     4.5    -      -       -      +
    624D  ILE*     4.2     9.3    -      -       -      +
----------------------------------------------------------
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Residues in contact with TYR 539 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    535D  MET*     2.9    41.3    +      -       +      -
    536D  GLU*     3.6     9.0    -      -       -      +
    538D  ARG*     1.3    77.8    -      -       -      +
    540D  ARG*     1.3    62.1    +      -       +      +
    541D  LEU      3.3     0.2    -      -       -      -
    542D  MET*     3.3    14.3    +      -       +      +
    543D  ALA*     2.9    29.4    +      -       -      +
    548D  ARG      5.7     2.2    -      -       -      -
    618D  LYS*     3.1    29.1    -      -       +      +
    619D  ALA*     2.8    26.3    +      -       -      -
    620D  ARG*     3.8     3.1    +      -       -      +
    621D  ALA*     4.0     8.2    +      -       +      +
    622D  ALA*     3.4    29.7    +      -       +      -
    501E  MET*     3.9    33.3    -      -       +      +
----------------------------------------------------------
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Residues in contact with ARG 540 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    533D  ALA      5.0     0.2    +      -       -      -
    536D  GLU*     2.9    62.8    +      -       -      +
    537D  ARG*     3.3    12.9    +      -       -      +
    539D  TYR*     1.3    76.6    -      -       +      +
    541D  LEU*     1.3    58.5    +      -       -      +
    543D  ALA*     3.3     6.1    +      -       -      +
    544D  ALA*     2.9    30.9    +      -       -      +
    570D  PRO      6.0     0.4    -      -       -      -
----------------------------------------------------------
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Residues in contact with LEU 541 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    537D  ARG*     2.9    27.7    +      -       -      +
    538D  ARG*     4.4     4.9    -      -       -      +
    539D  TYR      3.3     0.2    -      -       -      -
    540D  ARG*     1.3    74.5    -      -       -      +
    542D  MET*     1.3    59.7    +      -       -      +
    544D  ALA*     3.4     2.3    +      -       -      -
    545D  MET*     2.9    48.0    +      -       +      +
    553D  PHE*     3.5    31.4    -      -       +      -
    568D  THR      5.7     0.4    -      -       -      +
    569D  ASP*     5.0     8.3    -      -       +      -
    570D  PRO*     4.3    28.7    -      -       +      +
    587D  LEU*     4.1    20.0    -      -       +      -
----------------------------------------------------------
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Residues in contact with MET 542 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    538D  ARG*     3.1    21.9    +      -       +      +
    539D  TYR*     3.3    17.6    +      -       +      +
    541D  LEU*     1.3    77.4    -      -       +      +
    543D  ALA*     1.3    52.9    +      -       -      +
    545D  MET      3.2     0.3    +      -       -      -
    546D  GLY      2.6    31.2    +      -       -      -
    547D  VAL*     2.9    24.6    +      -       +      +
    548D  ARG*     4.0     6.7    -      -       -      +
    549D  ASN*     3.9    17.0    -      -       -      -
    550D  LEU*     3.5    34.3    -      -       +      +
    553D  PHE*     4.4    24.5    -      -       +      -
    587D  LEU*     5.4     1.1    -      -       +      -
    621D  ALA      3.5     5.8    -      -       -      +
    622D  ALA*     3.3    32.8    -      -       -      +
----------------------------------------------------------
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Residues in contact with ALA 543 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    539D  TYR      2.9    17.1    +      -       -      +
    540D  ARG*     3.6     7.9    -      -       -      +
    541D  LEU      3.2     0.2    -      -       -      -
    542D  MET*     1.3    76.4    -      -       -      +
    544D  ALA*     1.3    62.9    +      -       -      +
    546D  GLY*     3.2    14.2    +      -       -      -
    547D  VAL      4.6     1.8    -      -       -      -
----------------------------------------------------------
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Residues in contact with ALA 544 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    540D  ARG      2.9    17.6    +      -       -      +
    541D  LEU*     3.9     4.9    -      -       -      +
    543D  ALA*     1.3    76.5    -      -       -      +
    545D  MET*     1.3    63.4    +      -       -      +
    570D  PRO*     3.7    36.4    -      -       +      +
----------------------------------------------------------
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Residues in contact with MET 545 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    541D  LEU*     2.9    29.5    +      -       +      +
    542D  MET      3.8     2.0    -      -       -      +
    544D  ALA*     1.3    83.0    -      -       +      +
    546D  GLY*     1.3    56.2    +      -       -      +
    547D  VAL*     3.6     7.3    +      -       +      +
    553D  PHE*     3.4    31.6    -      -       +      -
    556D  LYS*     3.5    45.7    -      -       +      -
    557D  VAL*     5.2     3.1    -      -       +      -
    567D  LEU*     3.6    37.2    -      -       +      -
    568D  THR      4.7     2.7    -      -       -      +
    570D  PRO*     4.6    17.5    -      -       -      -
----------------------------------------------------------
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Residues in contact with GLY 546 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    542D  MET      2.6    12.1    +      -       -      -
    543D  ALA*     3.2    11.8    +      -       -      -
    545D  MET*     1.3    73.8    -      -       -      +
    547D  VAL*     1.3    65.7    +      -       -      +
    548D  ARG*     5.0     1.9    -      -       -      +
----------------------------------------------------------
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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