Contacts of the helix formed by residues 27 - 56 (chain B) in PDB entry 5XBY


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 ASP 27 (chain B).
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     25B  PRO*     4.2     3.9    -      -       -      +
     26B  PRO*     1.3    81.8    -      -       +      +
     28B  LEU*     1.3    61.9    +      -       -      +
     29B  VAL*     2.9    24.0    +      -       -      +
     30B  GLU*     3.3    23.5    +      -       +      +
     31B  PHE*     3.1    23.7    +      -       -      +
----------------------------------------------------------
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Residues in contact with LEU 28 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
      6A  PRO*     4.6    10.3    -      -       +      -
      7A  PRO      3.6    14.6    -      -       -      +
      8A  GLY*     3.8     5.8    -      -       -      +
      9A  LEU*     3.6    37.5    -      -       +      +
     12A  LEU*     3.7    15.9    -      -       +      +
     16B  TYR*     2.8    25.4    +      -       -      +
     20B  VAL*     3.9    30.7    -      -       +      -
     25B  PRO*     4.5    13.9    -      -       +      +
     26B  PRO      4.1     1.3    -      -       -      +
     27B  ASP*     1.3    73.4    +      -       -      +
     29B  VAL*     1.3    59.4    +      -       +      +
     31B  PHE*     3.6     3.0    +      -       -      +
     32B  ALA*     3.0    18.2    +      -       -      +
----------------------------------------------------------
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Residues in contact with VAL 29 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     12A  LEU*     3.7    27.1    -      -       +      -
     36A  PHE*     3.8    15.0    -      -       +      +
     39A  LEU*     4.3    14.1    -      -       +      +
     40A  ARG*     3.8    35.4    -      -       +      +
     27B  ASP*     2.9    11.4    +      -       -      +
     28B  LEU*     1.3    73.6    -      -       +      +
     30B  GLU*     1.3    67.5    +      -       -      +
     32B  ALA*     3.1     7.7    +      -       -      +
     33B  VAL*     3.0    22.3    +      -       -      +
----------------------------------------------------------
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Residues in contact with GLU 30 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     40A  ARG*     3.0    46.2    +      -       +      +
     27B  ASP*     3.3    26.7    +      -       +      +
     29B  VAL*     1.3    79.8    -      -       -      +
     31B  PHE*     1.3    62.2    +      -       -      +
     33B  VAL*     3.3     6.1    +      -       -      +
     34B  GLU*     3.0    50.8    +      -       -      +
----------------------------------------------------------
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Residues in contact with PHE 31 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     16B  TYR*     3.7    18.6    -      +       -      -
     19B  GLU*     4.1    24.0    -      -       +      -
     20B  VAL*     4.4     3.8    -      -       +      -
     23B  GLN*     3.7    45.8    -      -       +      -
     25B  PRO*     3.6    32.5    -      -       +      -
     27B  ASP      3.1    18.1    +      -       -      +
     28B  LEU      3.9     3.4    -      -       -      +
     30B  GLU*     1.3    73.9    -      -       -      +
     32B  ALA*     1.3    56.7    +      -       -      +
     34B  GLU*     3.2    18.0    +      -       +      +
     35B  TYR*     2.6    48.3    +      +       +      +
     38B  ARG*     4.6    14.1    -      -       -      -
----------------------------------------------------------
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Residues in contact with ALA 32 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     12A  LEU*     5.1     0.4    -      -       +      -
     32A  ALA      6.0     0.2    -      -       -      -
     36A  PHE*     3.7    35.7    -      -       +      -
     16B  TYR*     3.7    22.8    -      -       +      +
     28B  LEU      3.0    15.6    +      -       -      +
     29B  VAL      3.1     8.7    +      -       -      +
     31B  PHE*     1.3    73.0    -      -       -      +
     33B  VAL*     1.3    67.7    +      -       -      +
     35B  TYR      3.1     0.6    +      -       -      +
     36B  PHE*     2.9    34.3    +      -       +      +
----------------------------------------------------------
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Residues in contact with VAL 33 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     33A  VAL*     5.2     6.6    -      -       +      +
     36A  PHE*     3.7    32.5    -      -       -      +
     37A  THR*     3.7    18.4    -      -       -      +
     40A  ARG*     3.4    41.5    -      -       -      +
     29B  VAL      3.0    13.9    +      -       -      +
     30B  GLU*     3.6     7.6    -      -       -      +
     32B  ALA*     1.3    76.4    -      -       -      +
     34B  GLU*     1.3    61.3    +      -       +      +
     36B  PHE*     4.6     1.0    -      -       -      +
     37B  THR*     2.6    38.3    +      -       -      +
----------------------------------------------------------
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Residues in contact with GLU 34 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     30B  GLU*     3.0    43.8    +      -       -      +
     31B  PHE*     3.3    23.3    -      -       +      +
     33B  VAL*     1.3    78.6    -      -       +      +
     35B  TYR*     1.3    63.3    +      -       -      +
     37B  THR*     3.7     3.7    -      -       -      -
     38B  ARG*     3.1    60.0    +      -       -      +
----------------------------------------------------------
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Residues in contact with TYR 35 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     12B  LEU*     4.5     3.7    +      -       -      -
     15B  GLY*     3.5     8.3    -      -       -      -
     16B  TYR*     3.5    51.5    +      +       +      -
     19B  GLU*     3.6    33.6    -      -       +      +
     31B  PHE*     2.6    32.8    +      +       +      +
     32B  ALA      3.9     2.0    -      -       -      +
     34B  GLU*     1.3    73.0    -      -       -      +
     36B  PHE*     1.3    75.9    +      +       -      +
     38B  ARG*     3.3    10.0    +      -       -      +
     39B  LEU*     2.7    58.5    +      -       +      +
----------------------------------------------------------
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Residues in contact with PHE 36 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     13A  LEU*     5.9     0.4    -      -       +      -
     16A  TYR*     5.6     1.1    -      +       -      -
     29A  VAL*     3.9    10.6    -      -       +      +
     32A  ALA*     3.5    24.2    -      -       +      -
     33A  VAL*     3.5    20.9    -      -       +      +
     36A  PHE*     3.6    29.6    -      +       -      -
     12B  LEU*     3.6    35.9    -      -       +      -
     13B  LEU*     5.4     5.2    -      -       +      -
     16B  TYR*     4.1    22.9    -      +       +      -
     32B  ALA*     2.9    24.6    +      -       +      +
     33B  VAL      4.6     0.2    -      -       -      +
     35B  TYR*     1.3   101.0    -      +       -      +
     37B  THR*     1.3    57.9    +      -       -      +
     39B  LEU*     3.9    11.3    -      -       +      +
     40B  ARG*     2.7    34.1    +      -       -      +
----------------------------------------------------------
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Residues in contact with THR 37 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     33A  VAL*     3.7    22.6    -      -       -      +
     33B  VAL*     2.6    31.3    +      -       -      +
     34B  GLU*     3.7     5.2    -      -       -      -
     36B  PHE*     1.3    75.2    -      -       -      +
     38B  ARG*     1.3    58.9    +      -       +      +
     40B  ARG*     3.0    16.9    +      -       -      +
     41B  GLU*     2.8    51.8    +      -       +      +
----------------------------------------------------------
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Residues in contact with ARG 38 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     23B  GLN*     5.4     4.2    +      -       -      +
     31B  PHE*     4.6    14.3    -      -       -      -
     34B  GLU*     3.1    49.5    +      -       -      +
     35B  TYR*     3.7     6.4    -      -       -      +
     37B  THR*     1.3    76.7    -      -       +      +
     39B  LEU*     1.3    61.6    +      -       -      +
     41B  GLU*     3.9    18.1    -      -       -      +
     42B  ALA*     2.9    29.8    +      -       -      +
----------------------------------------------------------
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Residues in contact with LEU 39 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     29A  VAL*     4.3    14.6    -      -       +      -
     12B  LEU*     4.9     5.8    -      -       +      -
     35B  TYR*     2.7    52.8    +      -       +      +
     36B  PHE*     3.9    16.6    -      -       +      +
     38B  ARG*     1.3    73.8    -      -       -      +
     40B  ARG*     1.3    66.8    +      -       -      +
     42B  ALA*     3.6     7.8    +      -       +      +
     43B  ARG*     3.4    40.7    +      -       +      +
----------------------------------------------------------
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Residues in contact with ARG 40 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     29A  VAL*     3.9    17.1    -      -       +      +
     30A  GLU*     2.7    62.1    +      -       +      +
     33A  VAL*     3.9    31.6    -      -       +      +
     36B  PHE      2.7    22.3    +      -       -      +
     37B  THR*     3.0    16.3    +      -       -      +
     39B  LEU*     1.3    71.9    -      -       -      +
     41B  GLU*     1.3    58.8    +      -       -      +
     43B  ARG*     2.7    28.2    +      -       +      +
     44B  ASN*     3.0    28.9    +      -       -      +
----------------------------------------------------------
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Residues in contact with GLU 41 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     37B  THR*     2.8    42.0    +      -       +      +
     38B  ARG*     3.9    17.8    -      -       -      +
     40B  ARG*     1.3    74.7    -      -       +      +
     42B  ALA*     1.3    58.7    +      -       -      +
     44B  ASN*     3.1     8.5    +      -       -      +
     45B  LYS*     2.8    40.9    +      -       +      +
----------------------------------------------------------
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Residues in contact with ALA 42 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     38B  ARG      2.9    18.8    +      -       -      +
     39B  LEU*     3.7    13.5    -      -       +      +
     41B  GLU*     1.3    75.7    -      -       -      +
     43B  ARG*     1.3    58.9    +      -       +      +
     45B  LYS*     3.6     7.5    -      -       -      +
     46B  GLU*     2.8    44.5    +      -       -      +
----------------------------------------------------------
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Residues in contact with ARG 43 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     27A  ASP*     5.6     7.6    +      -       -      -
     29A  VAL*     3.2    36.6    -      -       -      +
     12B  LEU*     4.9     3.4    -      -       -      +
     39B  LEU*     3.4    31.7    +      -       +      +
     40B  ARG*     2.7    10.0    +      -       +      +
     42B  ALA*     1.3    80.1    -      -       +      +
     44B  ASN*     1.3    68.0    +      -       -      +
     46B  GLU*     3.7    11.2    -      -       -      +
     47B  GLN*     2.9    35.0    +      -       -      +
     77B  SER*     5.4    14.5    -      -       -      +
----------------------------------------------------------
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Residues in contact with ASN 44 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     40B  ARG*     3.0    35.1    +      -       -      +
     41B  GLU*     3.1     8.5    +      -       -      +
     43B  ARG*     1.3    76.6    -      -       -      +
     45B  LYS*     1.3    64.9    +      -       -      +
     47B  GLN*     3.0    13.1    +      -       -      +
     48B  GLN*     2.9    38.7    +      -       +      +
----------------------------------------------------------
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Residues in contact with LYS 45 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     41B  GLU*     2.8    24.3    +      -       +      +
     42B  ALA*     3.6     7.4    -      -       -      +
     44B  ASN*     1.3    77.5    -      -       -      +
     46B  GLU*     1.3    62.9    +      -       +      +
     47B  GLN      3.1     0.3    +      -       -      -
     48B  GLN*     3.4    20.7    +      -       -      +
     49B  ASN*     3.0    29.2    +      -       -      +
----------------------------------------------------------
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Residues in contact with GLU 46 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     42B  ALA*     2.8    35.5    +      -       -      +
     43B  ARG*     3.9    10.9    -      -       -      +
     45B  LYS*     1.3    74.7    -      -       +      +
     47B  GLN*     1.3    60.7    +      -       -      +
     49B  ASN*     4.0     6.3    +      -       -      +
     50B  ALA*     3.7    16.3    +      -       -      +
     79B  SER*     4.7     8.0    +      -       -      +
----------------------------------------------------------
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Residues in contact with GLN 47 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     43B  ARG*     2.9    27.1    +      -       -      +
     44B  ASN*     3.6    11.7    -      -       -      +
     46B  GLU*     1.3    73.5    -      -       -      +
     48B  GLN*     1.3    72.2    +      -       +      +
     50B  ALA*     3.1    11.4    +      -       -      +
     51B  PHE*     3.4     9.4    +      -       -      +
     72B  LEU*     4.4     9.6    +      -       +      +
     76B  PRO*     1.7    74.5    -      -       +      +
     79B  SER*     3.6    21.5    -      -       -      +
----------------------------------------------------------
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Residues in contact with GLN 48 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     44B  ASN*     2.9    34.0    +      -       +      +
     45B  LYS*     3.8    13.1    -      -       -      +
     47B  GLN*     1.3    79.3    -      -       -      +
     49B  ASN*     1.3    64.1    +      -       -      +
     51B  PHE*     3.0    22.6    +      -       -      +
     52B  TYR*     3.6    20.0    +      -       +      -
----------------------------------------------------------
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Residues in contact with ASN 49 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     45B  LYS*     3.0    34.5    +      -       -      +
     46B  GLU*     4.1     7.0    -      -       -      +
     47B  GLN      3.1     0.8    -      -       -      -
     48B  GLN*     1.3    81.7    -      -       -      +
     50B  ALA*     1.3    64.1    +      -       -      +
     52B  TYR*     3.6    12.5    +      -       -      +
     53B  GLU*     3.3    32.1    +      -       +      +
     83B  LEU*     5.5     0.2    -      -       -      -
----------------------------------------------------------
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Residues in contact with ALA 50 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     46B  GLU      3.7    10.0    +      -       -      +
     47B  GLN      3.1     9.9    +      -       -      +
     49B  ASN*     1.3    75.4    -      -       -      +
     51B  PHE*     1.3    65.8    +      -       -      +
     53B  GLU*     3.0    14.9    +      -       -      +
     54B  ILE*     3.1    18.0    +      -       +      +
     72B  LEU*     4.0    13.7    -      -       +      -
     79B  SER*     4.4    19.5    -      -       -      +
     83B  LEU*     4.1    28.9    -      -       +      +
----------------------------------------------------------
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Residues in contact with PHE 51 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     47B  GLN      3.4     4.3    +      -       -      +
     48B  GLN*     3.0    13.2    +      -       -      +
     50B  ALA*     1.3    77.1    -      -       -      +
     52B  TYR*     1.3    88.2    +      +       -      +
     54B  ILE*     3.6     6.3    -      -       -      +
     55B  LEU*     2.9    39.7    +      -       +      +
     69B  ILE*     3.6    41.5    -      -       +      +
     72B  LEU*     3.4    21.6    -      -       +      +
     73B  LYS*     6.0     7.2    -      -       +      -
----------------------------------------------------------
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Residues in contact with TYR 52 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     48B  GLN*     3.6    22.9    +      -       +      -
     49B  ASN*     4.0    11.4    -      -       -      +
     50B  ALA      3.2     0.4    -      -       -      -
     51B  PHE*     1.3   100.8    -      +       -      +
     53B  GLU*     1.3    60.1    +      -       +      +
     55B  LEU*     2.1    54.5    +      -       +      +
     56B  HIS*     3.3    12.3    +      -       +      +
----------------------------------------------------------
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Residues in contact with GLU 53 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     49B  ASN*     3.3    20.7    +      -       +      +
     50B  ALA      3.0     7.8    +      -       -      +
     52B  TYR*     1.3    83.0    -      -       +      +
     54B  ILE*     1.3    59.3    +      -       -      +
     56B  HIS*     3.2    29.0    +      -       +      +
     57B  LEU*     3.2    22.1    +      -       +      +
     83B  LEU*     3.8    26.4    -      -       +      +
     87B  LYS*     3.2    27.5    +      -       -      -
----------------------------------------------------------
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Residues in contact with ILE 54 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     50B  ALA*     3.1    14.1    +      -       +      +
     51B  PHE      3.6     6.5    -      -       -      +
     52B  TYR      2.7     1.8    +      -       -      -
     53B  GLU*     1.3    77.4    -      -       -      +
     55B  LEU*     1.3    62.9    +      -       -      +
     56B  HIS      3.3     0.5    +      -       -      -
     57B  LEU*     3.5    20.2    +      -       -      +
     60B  LEU*     4.3    10.7    -      -       +      +
     65B  ARG*     3.6    17.7    +      -       +      +
     68B  PHE*     4.2    31.0    -      -       +      +
     69B  ILE*     3.8    20.2    -      -       +      -
     72B  LEU*     4.2    22.2    -      -       +      -
     82B  LEU*     4.6    10.1    -      -       +      +
     83B  LEU*     4.3    16.8    -      -       +      +
     86B  ALA*     4.1    17.3    -      -       +      -
----------------------------------------------------------
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Residues in contact with LEU 55 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     51B  PHE*     2.9    28.3    +      -       +      +
     52B  TYR*     2.1    53.1    +      -       +      +
     54B  ILE*     1.3    68.8    -      -       -      +
     56B  HIS*     1.3    57.4    +      -       +      +
     65B  ARG*     3.1    29.7    +      -       -      +
     69B  ILE*     4.2    19.5    -      -       +      -
----------------------------------------------------------
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Residues in contact with HIS 56 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     52B  TYR*     4.0    16.9    -      -       +      +
     53B  GLU*     3.2    21.5    +      -       +      +
     55B  LEU*     1.3    79.3    -      -       +      +
     57B  LEU*     1.3    69.7    +      -       +      +
     58B  PRO*     3.0    13.6    -      -       -      +
     65B  ARG*     5.0     1.8    -      -       -      +
----------------------------------------------------------
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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