Contacts of the helix formed by residues 87 - 111 (chain B) in PDB entry 3PJA


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 PHE 87 (chain B).
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     17B  GLU*     4.5     7.6    -      -       +      -
     20B  ILE*     4.0    23.6    -      -       +      -
     21B  ARG*     3.6    59.0    -      -       +      -
     24B  ILE*     3.5    27.8    -      -       +      +
     83B  GLN*     4.5     4.1    +      -       -      -
     86B  ARG*     1.3   110.6    -      -       +      +
     88B  HIS*     1.3    63.8    +      -       -      +
     89B  GLU      3.2     2.9    -      -       -      -
     90B  HIS*     2.9    35.8    +      +       +      +
     91B  TRP*     3.0    20.0    -      -       +      +
----------------------------------------------------------
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Residues in contact with HIS 88 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     85B  TYR*     3.9    15.2    +      -       -      +
     86B  ARG      3.2     5.5    +      -       -      +
     87B  PHE*     1.3    75.5    -      -       -      +
     89B  GLU*     1.3    59.7    +      -       -      +
     90B  HIS      2.7    12.3    +      -       -      -
     91B  TRP*     3.4    29.9    +      +       +      +
     92B  ARG*     2.9    60.1    +      -       +      +
    136B  ASP*     3.5    16.7    +      -       +      +
    139B  ASP*     2.9    27.9    +      -       -      -
     86D  ARG*     5.9     6.7    -      -       +      -
----------------------------------------------------------
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Residues in contact with GLU 89 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     87B  PHE      3.0     2.0    +      -       -      -
     88B  HIS*     1.3    82.3    -      -       -      +
     90B  HIS*     1.3    69.6    +      -       +      +
     92B  ARG*     3.4    29.8    +      -       -      -
     93B  PHE*     3.3    33.8    -      -       +      -
----------------------------------------------------------
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Residues in contact with HIS 90 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     21B  ARG*     6.1     2.0    -      -       -      -
     24B  ILE*     5.4     7.2    -      -       +      -
     25B  ARG*     6.0     4.5    -      -       -      -
     28B  VAL*     4.4     9.4    -      -       +      +
     32B  GLU*     5.4     0.3    -      -       -      +
     87B  PHE*     2.9    32.5    +      +       +      +
     88B  HIS      2.7     7.5    +      -       -      -
     89B  GLU*     1.3    87.1    -      -       +      +
     91B  TRP*     1.3    61.8    +      -       +      +
     92B  ARG*     3.1     4.3    +      -       -      -
     93B  PHE*     4.3     9.9    +      -       -      -
     94B  VAL*     4.3     9.0    -      -       -      +
----------------------------------------------------------
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Residues in contact with TRP 91 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     24B  ILE*     4.7    11.9    -      -       +      +
     28B  VAL*     3.6    24.6    -      -       +      +
     31B  LEU*     6.6     0.2    -      -       +      -
     84B  TYR      3.3    28.9    -      -       -      -
     85B  TYR*     4.4     7.6    -      +       -      -
     87B  PHE*     3.0    44.3    +      -       +      +
     88B  HIS*     3.7    29.6    -      +       -      -
     90B  HIS*     1.3    74.7    -      -       +      +
     92B  ARG*     1.3    66.1    +      -       -      +
     93B  PHE      3.2     1.8    -      -       -      -
     94B  VAL*     3.5     6.2    +      -       +      +
     95B  LEU*     3.0    58.3    +      -       +      +
    133B  PHE*     4.2    32.4    -      +       +      -
    134B  HIS*     3.7    17.7    -      -       +      -
    139B  ASP*     4.9     0.2    -      -       -      -
----------------------------------------------------------
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Residues in contact with ARG 92 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     88B  HIS*     2.9    57.2    +      -       +      +
     89B  GLU*     3.4    31.3    +      -       -      -
     90B  HIS      3.1     1.0    -      -       -      -
     91B  TRP*     1.3    78.8    -      -       -      +
     93B  PHE*     1.3    77.9    +      -       +      +
     95B  LEU*     3.6     4.7    -      -       -      +
     96B  GLN*     2.9    49.2    +      -       -      +
    136B  ASP*     4.2     6.3    +      -       -      -
    138B  GLU*     3.8    15.2    -      -       -      +
    139B  ASP*     3.2    27.3    +      -       -      +
    142B  SER*     5.0     2.4    +      -       -      -
    188B  ASN*     3.7    24.6    -      -       -      +
    190B  SER*     4.5     9.7    +      -       -      -
    191B  LEU*     5.8     2.0    -      -       -      +
----------------------------------------------------------
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Residues in contact with PHE 93 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     89B  GLU*     3.3    46.0    -      -       +      -
     90B  HIS      4.3     8.0    +      -       -      -
     91B  TRP      3.2     0.4    -      -       -      -
     92B  ARG*     1.3    95.4    -      -       +      +
     94B  VAL*     1.3    66.4    +      -       +      +
     95B  LEU      3.1     0.7    -      -       -      -
     96B  GLN*     3.9    19.0    -      -       -      +
     97B  ARG*     3.0    25.5    +      -       -      +
    194B  ARG*     6.1     0.2    -      -       -      -
----------------------------------------------------------
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Residues in contact with VAL 94 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     28B  VAL*     3.6    20.4    -      -       +      -
     31B  LEU*     3.6    23.8    -      -       +      +
     32B  GLU*     3.5    60.8    -      -       +      +
     35B  ALA*     5.0     3.4    -      -       +      -
     90B  HIS      4.3     6.7    -      -       -      +
     91B  TRP*     4.1     9.2    -      -       +      +
     93B  PHE*     1.3    76.1    -      -       +      +
     95B  LEU*     1.3    57.5    +      -       -      +
     97B  ARG*     3.5     6.1    +      -       +      +
     98B  LEU*     3.0    38.5    +      -       +      +
----------------------------------------------------------
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Residues in contact with LEU 95 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     31B  LEU*     6.1     4.3    -      -       +      -
     72B  LEU*     5.7     3.4    -      -       +      -
     91B  TRP*     3.0    50.9    +      -       +      +
     92B  ARG      3.6     4.9    -      -       -      +
     94B  VAL*     1.3    75.7    -      -       -      +
     96B  GLN*     1.3    66.1    +      -       -      +
     98B  LEU*     3.2     8.3    +      -       +      +
     99B  VAL*     3.0    26.9    +      -       -      +
    123B  LEU*     4.6     9.2    -      -       +      -
    125B  ILE*     3.4    27.8    -      -       +      -
    134B  HIS      3.8     8.3    -      -       -      +
    135B  LEU*     3.7    22.9    -      -       +      -
    139B  ASP*     3.7    18.8    -      -       +      +
----------------------------------------------------------
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Residues in contact with GLN 96 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     92B  ARG*     2.9    44.7    +      -       -      +
     93B  PHE*     3.5    18.1    +      -       -      +
     95B  LEU*     1.3    75.4    -      -       -      +
     97B  ARG*     1.3    58.2    +      -       -      +
     99B  VAL*     3.2    10.0    +      -       -      +
    100B  PHE*     2.9    23.7    +      -       -      +
    139B  ASP*     3.1    38.5    +      -       -      +
    142B  SER*     3.4    24.6    +      -       -      -
    143B  GLY*     3.6     9.6    -      -       -      +
    146B  ILE*     4.7     7.2    -      -       +      -
    194B  ARG*     3.1    25.1    +      -       -      +
----------------------------------------------------------
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Residues in contact with ARG 97 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     32B  GLU      5.4     1.8    +      -       -      -
     35B  ALA*     3.9    24.7    -      -       +      +
     36B  ARG*     4.9     7.3    -      -       -      +
     39B  LEU*     4.1    29.5    -      -       -      +
     93B  PHE      3.0    18.8    +      -       -      +
     94B  VAL*     3.9     7.0    -      -       -      +
     96B  GLN*     1.3    78.7    -      -       -      +
     98B  LEU*     1.3    55.8    +      -       -      +
    100B  PHE*     3.4    14.1    +      -       +      +
    101B  LEU*     3.0    40.3    +      -       +      +
    146B  ILE*     4.9     5.6    -      -       +      +
----------------------------------------------------------
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Residues in contact with LEU 98 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     31B  LEU*     3.9    39.9    -      -       +      +
     35B  ALA*     3.9    30.7    -      -       +      +
     38B  ILE*     4.7     2.0    -      -       +      -
     65B  PHE*     4.2    21.9    -      -       +      -
     68B  VAL*     4.4    20.0    -      -       +      -
     94B  VAL*     3.0    24.4    +      -       +      +
     95B  LEU*     3.2     8.3    +      -       +      +
     97B  ARG*     1.3    73.9    -      -       -      +
     99B  VAL*     1.3    65.6    +      -       -      +
    101B  LEU*     3.6     6.5    +      -       +      +
    102B  ALA*     3.0    25.1    +      -       -      +
    123B  LEU*     4.1    18.6    -      -       +      +
----------------------------------------------------------
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Residues in contact with VAL 99 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     95B  LEU*     3.0    22.1    +      -       +      +
     96B  GLN*     3.2     9.8    +      -       -      +
     98B  LEU*     1.3    74.7    -      -       -      +
    100B  PHE*     1.3    66.1    +      -       -      +
    102B  ALA*     3.3     2.5    +      -       -      +
    103B  ALA*     2.9    23.6    +      -       +      +
    119B  VAL*     4.2    19.6    -      -       +      +
    123B  LEU*     4.6     4.9    -      -       +      -
    135B  LEU*     3.8    34.8    -      -       +      -
    140B  TYR*     3.9    41.5    -      -       +      +
    143B  GLY*     4.1     7.6    -      -       -      -
    144B  VAL*     4.9     2.0    -      -       +      +
----------------------------------------------------------
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Residues in contact with PHE 100 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     39B  LEU*     4.6    10.8    -      -       +      -
     96B  GLN      2.9    13.3    +      -       -      +
     97B  ARG*     3.4    20.4    -      -       +      +
     98B  LEU      3.3     0.2    -      -       -      -
     99B  VAL*     1.3    75.6    -      -       -      +
    101B  LEU*     1.3    86.9    +      -       +      +
    103B  ALA*     3.0     6.2    +      -       -      +
    104B  PHE*     2.9    37.0    +      +       +      -
    143B  GLY*     3.5    19.0    -      -       -      +
    146B  ILE*     3.4    24.7    -      -       +      -
    147B  LEU*     3.5    25.8    -      -       +      -
    150B  GLU*     3.6    44.4    -      -       +      -
----------------------------------------------------------
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Residues in contact with LEU 101 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     35B  ALA*     3.9    37.5    -      -       +      +
     38B  ILE*     4.0    17.3    -      -       +      -
     39B  LEU*     3.8    26.2    -      -       +      +
     42B  LEU*     4.6    13.8    -      -       +      +
     65B  PHE*     3.9    11.4    -      -       +      -
     97B  ARG*     3.0    26.4    +      -       +      +
     98B  LEU*     3.9    10.3    -      -       +      +
    100B  PHE*     1.3    99.6    -      -       +      +
    102B  ALA*     1.3    58.1    +      -       -      +
    104B  PHE*     3.2     7.9    +      -       +      +
    105B  VAL*     3.0    32.1    +      -       -      +
----------------------------------------------------------
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Residues in contact with ALA 102 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     65B  PHE*     3.5    24.6    -      -       +      -
     98B  LEU      3.0    20.2    +      -       -      +
     99B  VAL*     3.8     5.6    -      -       -      +
    101B  LEU*     1.3    76.3    -      -       -      +
    103B  ALA*     1.3    57.6    +      -       -      +
    105B  VAL*     3.2     3.0    +      -       -      +
    106B  VAL*     3.0    34.4    +      -       -      +
    114B  VAL*     4.7     0.4    -      -       -      -
    119B  VAL*     4.7    15.3    -      -       +      -
    122B  ILE*     4.7    17.9    -      -       +      -
    123B  LEU*     4.8     2.7    -      -       +      -
----------------------------------------------------------
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Residues in contact with ALA 103 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     99B  VAL*     2.9    21.9    +      -       +      +
    100B  PHE*     3.0     6.5    +      -       -      +
    102B  ALA*     1.3    76.1    -      -       -      +
    104B  PHE*     1.3    57.0    +      -       -      +
    106B  VAL*     3.5     3.3    +      -       -      +
    107B  TYR*     3.0    27.5    +      -       -      +
    112B  THR      4.6     2.4    -      -       -      +
    113B  LEU*     5.0     4.9    -      -       +      -
    114B  VAL*     3.5    26.6    +      -       +      +
    140B  TYR*     6.3     0.2    -      -       +      -
    143B  GLY      5.3     1.3    -      -       -      +
    144B  VAL*     5.4     5.2    -      -       +      -
    147B  LEU*     3.7    25.8    -      -       +      +
----------------------------------------------------------
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Residues in contact with PHE 104 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     42B  LEU*     3.7    36.8    -      -       +      -
     45B  VAL*     5.1     8.7    -      -       +      -
     46B  HIS*     5.3     3.8    -      +       -      -
    100B  PHE*     2.9    29.4    +      +       +      +
    101B  LEU*     3.3    10.5    -      -       +      +
    103B  ALA*     1.3    75.5    -      -       -      +
    105B  VAL*     1.3    58.8    +      -       -      +
    107B  TYR*     3.2     2.5    +      -       +      +
    108B  LEU*     3.0    56.6    +      -       +      +
    147B  LEU*     3.7    22.4    -      -       +      +
    150B  GLU*     3.9    27.1    -      -       +      -
    151B  LEU*     4.0    20.2    -      -       +      -
    154B  LEU*     4.4     9.0    -      -       +      -
----------------------------------------------------------
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Residues in contact with VAL 105 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     38B  ILE*     5.2     0.9    -      -       +      -
     42B  LEU*     4.7    15.3    -      -       +      -
     58B  CYS*     3.8    21.3    -      -       +      +
     61B  ALA*     3.7    27.4    -      -       +      -
     62B  ARG*     4.1    16.2    -      -       +      +
     65B  PHE*     4.3     9.6    -      -       +      -
    101B  LEU      3.0    15.6    +      -       -      +
    102B  ALA*     3.2     9.8    +      -       -      +
    104B  PHE*     1.3    76.6    -      -       -      +
    106B  VAL*     1.3    63.7    +      -       +      +
    108B  LEU*     3.2     5.5    +      -       +      +
    109B  GLU*     3.0    50.8    +      -       -      +
----------------------------------------------------------
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Residues in contact with VAL 106 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     62B  ARG*     4.0    21.3    -      -       -      +
    102B  ALA      3.0    17.7    +      -       -      +
    103B  ALA      3.8     4.7    -      -       -      +
    105B  VAL*     1.3    76.9    -      -       +      +
    107B  TYR*     1.3    57.6    +      -       -      +
    109B  GLU*     3.7     9.0    -      -       -      +
    110B  THR*     2.9    47.3    +      -       +      +
    112B  THR*     3.8    13.7    -      -       -      +
    114B  VAL*     3.8    36.8    -      -       +      +
    122B  ILE*     4.4     7.2    -      -       +      -
----------------------------------------------------------
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Residues in contact with TYR 107 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    103B  ALA      3.0    18.0    +      -       -      +
    104B  PHE*     3.6     8.5    -      -       +      +
    105B  VAL      3.1     0.4    -      -       -      -
    106B  VAL*     1.3    73.5    -      -       -      +
    108B  LEU*     1.3    69.2    +      -       +      +
    109B  GLU      3.0     4.5    -      -       -      -
    111B  GLU*     2.7    69.5    +      -       +      +
    112B  THR      3.8     6.7    -      -       -      +
    147B  LEU*     5.0     4.0    -      -       +      -
    151B  LEU*     3.9    34.8    -      -       +      -
    154B  LEU*     5.7     0.2    -      -       +      -
    166B  ARG*     5.6     7.4    -      -       +      +
    169B  HIS*     3.7    12.8    +      -       -      +
    170B  ILE*     3.5    37.4    +      -       +      +
    173B  PHE*     3.5    39.4    -      +       +      +
----------------------------------------------------------
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Residues in contact with LEU 108 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     42B  LEU*     5.0    10.3    -      -       +      -
     45B  VAL*     4.8    11.2    -      -       +      -
     54B  ILE*     3.9    45.8    -      -       +      +
     57B  ARG*     6.2     1.1    -      -       +      -
     58B  CYS*     3.9    13.0    -      -       -      -
    104B  PHE*     3.0    57.8    +      -       +      +
    105B  VAL*     3.2     6.7    +      -       -      +
    107B  TYR*     1.3    80.8    -      -       +      +
    109B  GLU*     1.3    59.5    +      -       -      +
    111B  GLU*     5.9     0.6    -      -       -      +
    154B  LEU*     4.4    14.8    -      -       +      -
    166B  ARG*     5.1    11.7    +      -       -      +
----------------------------------------------------------
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Residues in contact with GLU 109 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     55B  PRO*     6.3     0.7    -      -       +      -
     58B  CYS*     3.4    25.2    -      -       +      +
     59B  LEU*     6.0     0.9    -      -       -      +
     62B  ARG*     3.0    41.9    +      -       -      -
    105B  VAL*     3.0    34.9    +      -       -      +
    106B  VAL*     3.7     9.9    -      -       -      +
    107B  TYR      3.0     0.8    -      -       -      -
    108B  LEU*     1.3    81.4    -      -       -      +
    110B  THR*     1.3    70.9    +      -       +      +
    111B  GLU*     3.9     0.7    -      -       -      -
----------------------------------------------------------
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Residues in contact with THR 110 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    106B  VAL*     2.9    19.4    +      -       +      +
    109B  GLU*     1.3    92.7    -      -       +      +
    111B  GLU*     1.3    72.8    +      -       -      +
    112B  THR*     2.6    39.5    +      -       -      +
----------------------------------------------------------
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Residues in contact with GLU 111 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    107B  TYR*     2.7    59.2    +      -       +      +
    108B  LEU      5.9     0.4    -      -       -      +
    109B  GLU      5.8     0.4    -      -       -      -
    110B  THR*     1.3    73.6    -      -       -      +
    112B  THR*     1.3    61.9    +      -       -      +
    166B  ARG*     5.4     7.8    +      -       -      +
    169B  HIS*     3.3    45.4    +      -       +      +
    173B  PHE*     4.5     5.5    -      -       -      +
----------------------------------------------------------
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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