Contacts of the helix formed by residues 31 - 59 (chain B) in PDB entry 5SY1


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 CYS 31 (chain B).
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     29B  PRO*     3.8    14.1    +      -       -      -
     30B  PRO*     1.3    81.9    -      -       -      +
     32B  ASP*     1.3    59.3    +      -       -      +
     33B  PRO*     3.9     9.4    -      -       +      -
     34B  THR*     3.3    30.9    -      -       -      +
     35B  ALA*     3.0    27.1    +      -       -      +
    170B  ASP*     5.7     0.4    -      -       -      -
    171B  CYS*     3.6    33.2    -      -       -      -
----------------------------------------------------------
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Residues in contact with ASP 32 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     30B  PRO      4.2     0.4    -      -       -      -
     31B  CYS*     1.3    70.9    -      -       -      +
     33B  PRO*     1.3    68.4    -      -       +      +
     35B  ALA*     4.1     8.9    -      -       -      +
     36B  ASP*     3.2    22.0    +      -       -      +
    166B  TRP*     4.7     8.3    -      -       +      -
----------------------------------------------------------
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Residues in contact with PRO 33 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     31B  CYS*     3.6    11.2    -      -       +      -
     32B  ASP*     1.3    91.2    -      -       +      +
     34B  THR*     1.3    52.9    +      -       -      +
     36B  ASP*     3.0     4.6    +      -       +      +
     37B  GLU*     2.4    36.6    +      -       -      +
     40B  PHE*     4.1     3.5    -      -       +      -
    166B  TRP*     3.6    36.6    -      -       +      -
    167B  GLN*     3.8    28.5    -      -       +      +
    170B  ASP*     3.6    31.4    -      -       -      +
    171B  CYS*     5.3     1.6    -      -       -      -
----------------------------------------------------------
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Residues in contact with THR 34 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     31B  CYS*     3.2    29.9    +      -       -      +
     33B  PRO*     1.3    74.8    -      -       -      +
     35B  ALA*     1.3    62.5    +      -       -      +
     37B  GLU*     3.0    28.5    +      -       +      +
     38B  GLY      3.5     5.5    +      -       -      -
    167B  GLN*     5.7     1.1    -      -       -      +
----------------------------------------------------------
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Residues in contact with ALA 35 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     31B  CYS      3.0    16.3    +      -       -      +
     32B  ASP*     4.2    11.2    -      -       -      +
     34B  THR*     1.3    75.8    -      -       -      +
     36B  ASP*     1.3    58.8    +      -       -      +
     38B  GLY*     4.4     4.5    +      -       -      -
     39B  LEU*     4.6     4.3    +      -       -      +
----------------------------------------------------------
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Residues in contact with ASP 36 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     32B  ASP      3.2    18.4    +      -       -      +
     33B  PRO*     3.0     3.1    +      -       +      +
     35B  ALA*     1.3    73.8    -      -       -      +
     37B  GLU*     1.3    53.0    +      -       -      +
     38B  GLY      3.2     2.7    -      -       -      -
     39B  LEU*     2.9    31.8    +      -       -      +
     40B  PHE*     2.4    71.9    +      -       +      -
    166B  TRP*     5.4     2.9    -      -       +      -
----------------------------------------------------------
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Residues in contact with GLU 37 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     33B  PRO      2.4    25.3    +      -       -      +
     34B  THR*     3.0    18.8    +      -       +      +
     36B  ASP*     1.3    71.3    -      -       -      +
     38B  GLY*     1.3    49.4    +      -       -      +
     40B  PHE*     3.7    17.0    -      -       -      +
     41B  HIS*     2.5    73.8    +      -       +      -
    163B  ILE*     4.4     3.3    -      -       -      +
    167B  GLN*     2.4    34.1    +      -       -      +
----------------------------------------------------------
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Residues in contact with GLY 38 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     34B  THR      3.5     8.0    +      -       -      -
     35B  ALA      4.4     3.1    +      -       -      -
     36B  ASP      3.2     0.8    -      -       -      -
     37B  GLU*     1.3    78.4    -      -       -      +
     39B  LEU*     1.3    56.5    +      -       -      +
     41B  HIS*     3.7    12.0    +      -       -      +
     42B  ILE*     3.3    27.5    +      -       -      +
    113B  PHE*     4.8    12.3    -      -       -      -
----------------------------------------------------------
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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
----------------------------------------------------------
     35B  ALA      4.6     3.0    +      -       -      +
     36B  ASP*     2.9    29.0    +      -       -      +
     38B  GLY*     1.3    75.7    -      -       -      +
     40B  PHE*     1.3    52.9    +      -       -      +
     41B  HIS      3.2     1.3    -      -       -      -
     42B  ILE*     3.0    26.8    +      -       +      +
     43B  CYS*     2.6    41.9    +      -       +      +
----------------------------------------------------------
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Residues in contact with PHE 40 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     33B  PRO*     4.1     4.0    -      -       +      -
     36B  ASP*     2.4    70.4    +      -       +      +
     37B  GLU*     3.2    26.7    +      -       -      +
     39B  LEU*     1.3    65.7    -      -       -      +
     41B  HIS*     1.3    64.6    +      -       -      +
     43B  CYS*     3.8    16.8    -      -       +      -
     44B  ILE*     3.3    28.2    +      -       +      +
    163B  ILE*     4.0    40.6    -      -       +      -
    166B  TRP*     4.2    25.6    -      +       -      -
    167B  GLN*     4.9     1.1    -      -       -      -
----------------------------------------------------------
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Residues in contact with HIS 41 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     37B  GLU*     2.5    64.9    +      -       +      +
     38B  GLY*     3.7    13.2    -      -       -      +
     40B  PHE*     1.3    74.8    -      -       -      +
     42B  ILE*     1.3    60.6    +      -       -      +
     44B  ILE*     5.5     0.2    -      -       -      -
     45B  ALA*     3.4    25.1    +      -       -      +
    110B  PRO      5.2     3.1    -      -       -      -
    111B  LEU*     3.4    32.4    -      -       +      +
    113B  PHE*     3.8    34.5    -      +       +      +
    130B  TYR*     4.0    19.4    +      +       -      -
    131B  TYR*     5.5     2.4    +      -       -      -
    134B  LEU*     6.2     1.1    -      -       +      -
----------------------------------------------------------
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Residues in contact with ILE 42 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     38B  GLY      3.3    17.9    -      -       -      +
     39B  LEU*     3.0    28.7    +      -       +      +
     41B  HIS*     1.3    77.5    -      -       +      +
     43B  CYS*     1.3    65.1    +      -       -      +
     45B  ALA*     4.1     2.2    -      -       -      +
     46B  ALA*     3.2    23.3    +      -       +      +
    113B  PHE*     5.2     9.0    -      -       +      -
    114B  THR*     5.4    13.0    -      -       +      +
----------------------------------------------------------
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Residues in contact with CYS 43 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     39B  LEU*     2.6    25.5    +      -       +      +
     40B  PHE*     4.1    18.6    -      -       +      -
     41B  HIS      3.4     0.2    -      -       -      -
     42B  ILE*     1.3    73.6    -      -       -      +
     44B  ILE*     1.3    70.8    +      -       +      +
     46B  ALA*     3.1    16.2    +      -       -      +
     47B  ILE*     3.1    28.6    +      -       -      +
----------------------------------------------------------
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Residues in contact with ILE 44 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     40B  PHE*     3.3    20.6    +      -       +      +
     41B  HIS*     5.0     0.4    -      -       -      +
     43B  CYS*     1.3    85.0    -      -       +      +
     45B  ALA*     1.3    58.4    +      -       -      +
     47B  ILE*     2.8    14.8    +      -       +      +
     48B  SER*     2.8    29.8    +      -       -      -
    134B  LEU*     4.3    19.7    -      -       +      -
    156B  LEU*     6.6     0.2    -      -       +      -
    159B  THR*     3.8    19.5    -      -       +      -
    160B  HIS*     3.5    33.7    -      -       +      +
    163B  ILE*     3.8    31.4    -      -       +      -
----------------------------------------------------------
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Residues in contact with ALA 45 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     41B  HIS      3.4    19.8    +      -       -      +
     42B  ILE*     4.3     2.5    -      -       -      +
     43B  CYS      3.3     0.4    -      -       -      -
     44B  ILE*     1.3    78.3    -      -       -      +
     46B  ALA*     1.3    60.6    +      -       -      +
     48B  SER*     3.4    18.3    +      -       -      +
     49B  LEU*     3.4    17.2    +      -       -      +
    130B  TYR*     4.0    19.7    +      -       +      +
    134B  LEU*     5.4     4.4    -      -       +      +
----------------------------------------------------------
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Residues in contact with ALA 46 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     42B  ILE*     3.2    15.3    +      -       +      +
     43B  CYS*     3.1    13.0    +      -       -      +
     45B  ALA*     1.3    76.4    -      -       -      +
     47B  ILE*     1.3    67.6    +      -       +      +
     49B  LEU*     3.8     4.8    +      -       -      +
     50B  VAL*     3.3    25.8    +      -       -      +
----------------------------------------------------------
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Residues in contact with ILE 47 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     43B  CYS*     3.2    26.9    -      -       -      +
     44B  ILE*     2.8    19.1    +      -       +      +
     46B  ALA*     1.3    81.9    -      -       +      +
     48B  SER*     1.3    62.6    +      -       -      +
     50B  VAL*     3.2    15.1    +      -       +      +
     51B  VAL*     3.3    19.5    +      -       +      +
    156B  LEU*     3.7    29.8    -      -       +      -
----------------------------------------------------------
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Residues in contact with SER 48 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     44B  ILE*     2.8    17.6    +      -       -      -
     45B  ALA*     3.4    17.7    +      -       -      +
     47B  ILE*     1.3    74.0    -      -       -      +
     49B  LEU*     1.3    62.9    +      -       -      +
     51B  VAL*     5.0     0.9    -      -       -      -
     52B  MET*     3.2    31.1    +      -       -      +
    133B  THR*     4.7     3.8    +      -       -      +
    134B  LEU*     3.8    32.0    -      -       -      -
    137B  PRO*     3.7    15.1    -      -       -      +
    156B  LEU*     6.1     1.8    -      -       -      -
----------------------------------------------------------
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Residues in contact with LEU 49 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     45B  ALA      3.4    15.6    +      -       -      +
     46B  ALA*     4.3     4.7    -      -       -      +
     47B  ILE      3.2     0.8    -      -       -      -
     48B  SER*     1.3    80.5    +      -       -      +
     50B  VAL*     1.3    66.6    +      -       +      +
     52B  MET*     3.9    13.7    +      -       +      +
     53B  LEU*     3.5    37.4    +      -       +      +
----------------------------------------------------------
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Residues in contact with VAL 50 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     46B  ALA      3.3    17.9    -      -       -      +
     47B  ILE*     3.2     9.3    +      -       +      +
     49B  LEU*     1.3    78.1    -      -       +      +
     51B  VAL*     1.3    64.3    +      -       +      +
     53B  LEU*     3.0     8.7    +      -       -      +
     54B  VAL*     2.9    39.5    +      -       +      +
----------------------------------------------------------
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Residues in contact with VAL 51 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     47B  ILE*     3.3    24.5    +      -       +      +
     48B  SER      3.9     0.2    +      -       -      -
     50B  VAL*     1.3    79.4    -      -       +      +
     52B  MET*     1.3    61.6    +      -       -      +
     54B  VAL*     3.4     8.8    +      -       +      +
     55B  LEU*     3.3    32.7    +      -       +      +
    137B  PRO*     3.9    27.4    -      -       +      +
    141B  CYS*     5.3     3.1    -      -       -      -
    152B  LEU*     4.6    33.4    -      -       +      -
    156B  LEU*     4.3    22.4    -      -       +      -
----------------------------------------------------------
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Residues in contact with MET 52 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     48B  SER*     3.2    23.0    +      -       -      +
     49B  LEU*     4.1    15.9    -      -       +      +
     50B  VAL      3.2     0.6    -      -       -      -
     51B  VAL*     1.3    79.7    -      -       -      +
     53B  LEU*     1.3    64.4    +      -       +      +
     55B  LEU*     3.5     9.6    +      -       -      +
     56B  ALA*     3.3    15.1    +      -       -      +
     74B  LEU*     3.7    34.8    -      -       +      +
    133B  THR*     4.2    27.4    -      -       +      +
    136B  TYR*     3.5    41.3    -      -       +      -
    137B  PRO*     3.7     9.0    -      -       +      -
----------------------------------------------------------
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Residues in contact with LEU 53 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     49B  LEU*     3.5    28.7    +      -       +      +
     50B  VAL*     3.0     9.2    +      -       -      +
     52B  MET*     1.3    79.9    -      -       +      +
     54B  VAL*     1.3    65.0    +      -       +      +
     55B  LEU      3.3     0.4    -      -       -      -
     56B  ALA*     3.4    14.8    +      -       +      +
     57B  ILE*     3.3    27.4    +      -       +      +
     74B  LEU*     5.7     3.6    -      -       +      -
----------------------------------------------------------
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Residues in contact with VAL 54 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     50B  VAL*     2.9    32.3    +      -       +      +
     51B  VAL*     3.7    11.2    -      -       -      +
     52B  MET      3.4     0.2    -      -       -      -
     53B  LEU*     1.3    77.2    -      -       -      +
     55B  LEU*     1.3    59.1    +      -       +      +
     57B  ILE*     3.0    28.5    +      -       +      +
     58B  LEU*     3.1    29.1    +      -       +      +
    148B  VAL*     5.1     2.7    -      -       +      -
    152B  LEU*     4.5    20.6    -      -       +      -
----------------------------------------------------------
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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  VAL*     3.3    27.9    +      -       +      +
     52B  MET*     3.7     9.9    -      -       -      +
     53B  LEU      3.3     0.2    -      -       -      -
     54B  VAL*     1.3    77.1    -      -       +      +
     56B  ALA*     1.3    62.0    +      -       -      +
     58B  LEU*     3.9    15.1    -      -       +      +
     59B  ALA*     3.3    23.4    +      -       -      +
     74B  LEU*     5.6     2.5    -      -       +      -
     75B  LEU*     3.7    26.3    +      -       +      +
    136B  TYR*     5.9     1.3    -      -       +      -
    137B  PRO*     5.3     2.9    -      -       +      +
    140B  ALA*     3.7    34.3    -      -       +      +
    141B  CYS*     5.0     5.8    -      -       -      +
    144B  LEU*     3.7    30.1    -      -       +      -
    148B  VAL*     5.7     3.1    -      -       +      -
    149B  GLY*     6.1     3.1    -      -       -      -
    152B  LEU*     5.7     3.8    -      -       +      -
----------------------------------------------------------
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Residues in contact with ALA 56 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     52B  MET      3.3    11.9    +      -       -      +
     53B  LEU*     3.5    21.8    -      -       +      +
     54B  VAL      3.2     0.6    -      -       -      -
     55B  LEU*     1.3    76.9    -      -       -      +
     57B  ILE*     1.3    63.9    +      -       +      +
     59B  ALA*     3.9     5.6    +      -       -      +
     60B  ARG*     3.7    27.6    +      -       -      +
     73B  GLY      5.1    10.2    -      -       -      +
     74B  LEU*     4.9    11.8    -      -       +      +
----------------------------------------------------------
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Residues in contact with ILE 57 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     53B  LEU*     3.3    17.0    -      -       +      +
     54B  VAL*     3.0    18.0    +      -       +      +
     56B  ALA*     1.3    77.9    -      -       +      +
     58B  LEU*     1.3    61.6    +      -       +      +
     60B  ARG*     3.1    22.1    +      -       -      +
     61B  ARG*     3.3    46.8    +      -       -      +
----------------------------------------------------------
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Residues in contact with LEU 58 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     54B  VAL*     3.1    22.3    +      -       +      +
     55B  LEU*     3.7    22.2    +      -       +      +
     57B  ILE*     1.3    77.9    -      -       +      +
     59B  ALA*     1.3    57.4    +      -       -      +
     61B  ARG*     3.0    41.0    +      -       +      +
     62B  GLN*     3.1    35.2    +      -       +      +
     64B  LEU*     5.6     0.4    -      -       -      -
    144B  LEU*     4.5    12.8    -      -       +      -
    146B  ASN*     5.1     3.6    -      -       -      +
    148B  VAL*     3.8    35.9    -      -       +      -
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Residues in contact with ALA 59 (chain B). Click here for Legend to table.
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                                  Specific contacts
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     Residue       Dist    Surf   HB    Arom    Phob    DC
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     55B  LEU      3.3    18.8    +      -       -      +
     56B  ALA      4.2     5.2    -      -       -      +
     57B  ILE      3.2     0.6    -      -       -      -
     58B  LEU*     1.3    77.1    -      -       -      +
     60B  ARG*     1.3    59.7    +      -       +      +
     61B  ARG      3.2     1.4    +      -       -      -
     62B  GLN      3.9     5.1    +      -       -      +
     63B  LYS*     4.0     8.0    +      -       -      +
     64B  LEU*     4.2    19.6    +      -       +      -
     68B  GLN*     3.0    40.7    +      -       +      +
     73B  GLY      4.5    10.5    -      -       -      +
     75B  LEU*     4.6     6.7    -      -       +      -
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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
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  Atomic class           I  II  III   IV   V   VI  VII  VIII
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   I  (Hydrophilic)      +   +    +    -   +   +    +    +
  II  (Acceptor)         +   -    +    -   +   +    +    -
 III  (Donor)            +   +    -    -   +   +    -    +
  IV  (Hydrophobic)      -   -    -    +   +   +    +    +
   V  (Aromatic)         +   +    +    +   +   +    +    +
  VI  (Neutral)          +   +    +    +   +   +    +    +
 VII  (Neutral-donor)    +   +    -    +   +   +    -    +
VIII  (Neutral-acceptor) +   -    +    +   +   +    +    -
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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