Contacts of the helix formed by residues 28 - 50 (chain B) in PDB entry 1FTA


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 GLY 28 (chain B).
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     26B  GLY      3.1     4.3    -      -       -      -
     27B  THR*     1.3    77.5    -      -       -      +
     29B  GLU*     1.3    59.7    +      -       -      +
     30B  LEU      3.6     1.6    -      -       -      -
     31B  THR*     3.7    13.7    -      -       -      -
     32B  GLN*     3.0    33.8    +      -       -      +
    338B  AMP      2.9     4.7    +      -       -      -
     18D  MET*     4.1    12.0    -      -       -      +
     22D  ARG*     3.3    15.1    -      -       -      -
----------------------------------------------------------
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Residues in contact with GLU 29 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     27B  THR*     3.6     7.0    +      -       -      +
     28B  GLY*     1.3    75.3    -      -       -      +
     30B  LEU*     1.3    65.5    +      -       -      +
     32B  GLN*     3.2     7.4    +      -       +      +
     33B  LEU*     3.0    20.8    +      -       -      +
     88B  SER      5.8     0.2    -      -       -      +
     89B  PHE      4.3     5.4    -      -       -      +
     90B  ALA*     3.4    26.9    -      -       +      +
    111B  GLY*     4.2     5.0    -      -       -      -
    112B  LYS*     3.0    57.3    +      -       -      +
    113B  TYR*     3.4     5.8    -      -       +      -
    338B  AMP      3.0    16.0    +      -       -      +
     22D  ARG*     3.4    13.1    -      -       -      +
----------------------------------------------------------
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Residues in contact with LEU 30 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     29B  GLU*     1.3    77.1    -      -       -      +
     31B  THR*     1.3    57.3    +      -       -      +
     33B  LEU*     2.9    28.7    +      -       +      +
     34B  LEU*     2.8    49.7    +      -       +      +
    113B  TYR*     4.0    17.0    -      -       +      +
    138B  ILE*     4.2    19.7    -      -       +      -
    160B  VAL*     4.0    14.4    -      -       +      -
    161B  ALA*     5.1     7.6    -      -       +      -
    177B  MET*     5.4     2.0    -      -       -      -
    338B  AMP      3.2    59.9    +      -       +      +
----------------------------------------------------------
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Residues in contact with THR 31 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     17B  VAL*     3.6    19.2    +      -       +      -
     18B  MET*     4.2    19.7    +      -       +      -
     21B  GLY*     3.8     7.4    -      -       -      -
     28B  GLY*     3.7    16.9    +      -       -      -
     30B  LEU*     1.3    75.1    -      -       -      +
     32B  GLN*     1.4    56.3    +      -       -      +
     34B  LEU*     3.2     3.5    +      -       -      +
     35B  ASN*     2.9    41.0    +      -       -      +
    338B  AMP      3.0    31.1    +      -       -      -
     18D  MET*     4.2    19.5    -      -       -      -
----------------------------------------------------------
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Residues in contact with GLN 32 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     28B  GLY      3.0    22.3    +      -       -      +
     29B  GLU*     3.6     6.1    -      -       +      +
     31B  THR*     1.4    73.4    -      -       -      +
     33B  LEU*     1.3    57.2    +      -       -      +
     35B  ASN*     3.5    17.4    +      -       -      +
     36B  SER*     2.7    32.7    +      -       -      -
     88B  SER*     3.8    20.0    -      -       -      +
     15D  ARG*     3.3    38.8    -      -       -      +
     18D  MET*     3.4    31.3    -      -       +      +
     19D  GLU*     3.4    17.0    +      -       +      +
     22D  ARG*     4.6    11.7    -      -       -      +
----------------------------------------------------------
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Residues in contact with LEU 33 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     29B  GLU      3.0    11.4    +      -       -      +
     30B  LEU*     2.9    27.7    +      -       +      +
     32B  GLN*     1.3    75.7    -      -       -      +
     34B  LEU*     1.3    65.2    +      -       -      +
     36B  SER*     3.2     5.0    +      -       -      -
     37B  LEU*     3.1    21.6    +      -       +      +
     85B  LEU*     3.5    31.9    -      -       +      -
     88B  SER*     3.7    16.2    -      -       -      +
     90B  ALA*     3.6     8.5    -      -       +      +
     91B  THR*     3.7    12.1    -      -       +      -
    113B  TYR*     3.9    30.3    -      -       +      -
    115B  VAL*     4.1     8.1    -      -       +      -
    138B  ILE*     3.9    18.4    -      -       +      -
----------------------------------------------------------
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Residues in contact with LEU 34 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     13B  LEU*     5.2     3.2    -      -       +      +
     17B  VAL*     3.9    33.0    -      -       +      -
     30B  LEU*     2.8    55.5    +      -       +      +
     31B  THR      3.8     3.4    -      -       -      +
     33B  LEU*     1.3    71.9    -      -       -      +
     35B  ASN*     1.3    62.0    +      -       -      +
     37B  LEU*     3.3    12.2    +      -       +      +
     38B  CYS*     2.9    22.7    +      -       -      +
    136B  PHE*     5.3     3.1    -      -       +      -
    138B  ILE*     3.9    26.5    -      -       +      -
    161B  ALA*     5.0     3.6    -      -       +      -
    175B  LEU*     4.6    24.0    -      -       +      -
    177B  MET*     5.2     6.5    -      -       -      -
    338B  AMP      4.3     6.5    -      -       +      +
----------------------------------------------------------
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Residues in contact with ASN 35 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     13B  LEU*     5.9     2.2    -      -       -      +
     14B  THR*     4.3    25.5    +      -       -      +
     17B  VAL*     4.2    16.6    -      -       -      +
     18B  MET*     6.2     0.2    -      -       -      +
     31B  THR*     2.9    28.2    +      -       -      +
     32B  GLN*     3.5    25.0    +      -       -      +
     34B  LEU*     1.3    75.0    -      -       -      +
     36B  SER*     1.3    62.8    +      -       -      +
     38B  CYS*     2.9    21.6    +      -       -      +
     39B  THR*     3.0    16.3    +      -       -      +
     14D  THR*     3.7    25.9    -      -       +      +
     15D  ARG*     5.8     1.8    -      -       +      +
     18D  MET*     4.8     2.9    -      -       -      +
----------------------------------------------------------
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Residues in contact with SER 36 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     32B  GLN      2.7    21.9    +      -       -      -
     33B  LEU      3.2     5.1    +      -       -      -
     35B  ASN*     1.3    75.9    -      -       -      +
     37B  LEU*     1.3    62.5    +      -       -      +
     39B  THR*     3.4     8.6    +      -       -      -
     40B  ALA*     3.0    22.9    +      -       -      +
     84B  MET*     3.7    26.3    -      -       -      +
     85B  LEU*     4.7     3.1    -      -       -      -
     88B  SER*     3.3    12.2    -      -       -      -
     15D  ARG*     2.9    33.4    +      -       -      +
----------------------------------------------------------
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Residues in contact with LEU 37 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     33B  LEU*     3.1    12.3    +      -       +      +
     34B  LEU*     3.3    18.6    -      -       +      +
     36B  SER*     1.3    77.3    -      -       -      +
     38B  CYS*     1.3    61.0    +      -       -      +
     40B  ALA*     3.2     7.6    +      -       +      +
     41B  VAL*     3.0    37.9    +      -       +      +
     81B  VAL*     4.5    11.7    -      -       +      -
     85B  LEU*     3.6    31.8    -      -       +      +
    115B  VAL*     4.8     8.7    -      -       +      -
    117B  PHE*     6.2     0.2    -      -       +      -
    134B  THR*     5.7     2.2    -      -       +      -
    136B  PHE*     3.7    52.0    -      -       +      -
    138B  ILE*     5.4     4.3    -      -       +      -
    173B  LEU*     5.3     2.0    -      -       +      -
----------------------------------------------------------
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Residues in contact with CYS 38 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     13B  LEU*     3.6    35.2    -      -       +      -
     14B  THR*     4.7    12.1    -      -       -      -
     34B  LEU      2.9     9.9    +      -       -      +
     35B  ASN*     2.9    15.7    +      -       -      +
     37B  LEU*     1.3    75.5    -      -       -      +
     39B  THR*     1.3    63.3    +      -       -      +
     41B  VAL*     3.2     9.6    +      -       -      +
     42B  LYS*     3.1    37.6    +      -       -      +
    173B  LEU*     5.8     3.6    -      -       -      -
    193B  PHE*     4.0    17.5    -      -       -      -
    192D  GLU*     5.6     0.2    -      -       -      -
----------------------------------------------------------
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Residues in contact with THR 39 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     35B  ASN*     3.0    13.0    +      -       -      +
     36B  SER*     3.7     9.4    -      -       -      -
     38B  CYS*     1.3    74.7    -      -       -      +
     40B  ALA*     1.3    65.4    +      -       -      +
     42B  LYS*     3.1    14.7    +      -       -      +
     43B  ALA*     3.0    21.4    +      -       -      +
     84B  MET*     4.0    12.6    -      -       -      -
     59C  ILE*     3.9    24.9    -      -       +      -
     12D  THR*     4.2    12.3    +      -       +      +
     14D  THR*     6.1     0.7    -      -       -      -
    190D  ILE*     4.8     2.8    -      -       +      +
    192D  GLU*     3.7    34.1    +      -       +      +
----------------------------------------------------------
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Residues in contact with ALA 40 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     36B  SER      3.0    13.2    +      -       -      +
     37B  LEU*     3.4    12.8    -      -       +      +
     39B  THR*     1.3    76.2    -      -       -      +
     41B  VAL*     1.3    59.4    +      -       +      +
     43B  ALA*     3.1     8.6    +      -       -      +
     44B  ILE*     2.9    33.9    +      -       +      +
     80B  LEU*     4.3     5.8    -      -       -      +
     81B  VAL*     4.2    26.9    -      -       +      +
     84B  MET*     4.2    19.9    -      -       +      +
     59C  ILE*     5.9     0.2    -      -       -      -
----------------------------------------------------------
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Residues in contact with VAL 41 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     37B  LEU*     3.0    30.0    +      -       +      +
     38B  CYS*     3.2     9.6    +      -       -      +
     40B  ALA*     1.3    75.7    -      -       +      +
     42B  LYS*     1.3    56.0    +      -       -      +
     44B  ILE*     3.3     5.1    +      -       +      +
     45B  SER*     2.8    26.9    +      -       -      -
    134B  THR*     4.8    11.4    -      -       +      -
    136B  PHE*     5.3     0.7    -      -       +      -
    165B  ALA*     3.4    33.7    -      -       +      -
    167B  TYR*     3.6    16.2    +      -       +      +
    171B  THR*     4.6     0.7    -      -       +      -
    173B  LEU*     4.2    10.3    -      -       +      -
    193B  PHE*     3.8    23.6    -      -       +      -
----------------------------------------------------------
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Residues in contact with LYS 42 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     38B  CYS*     3.1    24.8    +      -       -      +
     39B  THR*     3.1    11.4    +      -       -      +
     41B  VAL*     1.3    74.9    -      -       -      +
     43B  ALA*     1.3    63.3    +      -       -      +
     45B  SER*     3.1     8.2    +      -       -      -
     46B  SER*     3.0    25.6    +      -       -      -
    186B  LEU*     3.8    22.3    -      -       +      +
    191B  GLY*     3.0    26.8    +      -       -      +
    192B  GLU*     5.0     2.4    +      -       -      +
    193B  PHE*     3.8    19.1    -      -       +      -
     42D  LYS*     4.3     2.6    -      -       -      +
    189D  ALA      4.9     0.3    -      -       -      +
    190D  ILE*     3.2    32.5    +      -       +      +
    191D  GLY      3.3     4.2    +      -       -      -
    192D  GLU*     2.8    29.6    +      -       -      -
----------------------------------------------------------
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Residues in contact with ALA 43 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     39B  THR      3.0    11.3    +      -       -      +
     40B  ALA*     3.1     9.6    +      -       -      +
     42B  LYS*     1.3    77.8    -      -       -      +
     44B  ILE*     1.3    61.5    +      -       -      +
     46B  SER*     3.6     3.1    +      -       -      -
     47B  ALA*     3.2    21.7    +      -       -      +
     80B  LEU*     3.8    29.9    -      -       +      +
     55C  HIS*     5.4     9.8    -      -       +      +
     59C  ILE*     4.2    17.9    -      -       +      -
    190D  ILE*     3.6    15.4    -      -       +      +
----------------------------------------------------------
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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  ALA*     2.9    25.0    +      -       +      +
     41B  VAL*     3.7     5.6    -      -       +      +
     43B  ALA*     1.3    75.1    -      -       -      +
     45B  SER*     1.3    58.5    +      -       -      +
     47B  ALA*     3.0     5.7    +      -       -      +
     48B  VAL*     2.8    33.1    +      -       +      +
     73B  LEU*     5.7     0.2    -      -       +      -
     77B  SER*     3.6    28.3    -      -       -      +
     80B  LEU*     3.7    20.2    -      -       +      -
     81B  VAL*     3.8    29.4    -      -       +      -
    119B  PRO      4.4     0.9    -      -       -      +
    120B  LEU*     3.7    19.3    -      -       +      -
    134B  THR*     4.0    16.8    -      -       +      +
    167B  TYR*     3.7    18.2    -      -       +      +
----------------------------------------------------------
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Residues in contact with SER 45 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     41B  VAL      2.8    17.7    +      -       -      -
     42B  LYS*     3.1     9.4    +      -       -      -
     44B  ILE*     1.3    73.9    -      -       -      +
     46B  SER*     1.3    62.0    +      -       -      +
     48B  VAL*     3.2     3.4    +      -       -      +
     49B  ARG*     3.1    38.2    +      -       -      -
    167B  TYR*     3.9    16.7    -      -       -      -
    171B  THR*     2.7    34.8    +      -       -      -
    186B  LEU*     4.0    10.5    -      -       -      +
----------------------------------------------------------
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Residues in contact with SER 46 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     42B  LYS      3.0    14.4    +      -       -      -
     43B  ALA      3.8     4.9    -      -       -      -
     45B  SER*     1.3    77.3    -      -       -      +
     47B  ALA*     1.3    61.2    +      -       -      +
     49B  ARG*     3.4     8.7    +      -       -      +
     50B  LYS      3.5     0.2    +      -       -      -
     51B  ALA*     3.4    39.0    +      -       -      +
     55C  HIS*     6.1     2.8    -      -       -      -
    189D  ALA*     3.3    34.1    +      -       -      +
    190D  ILE*     4.2     6.0    -      -       -      +
----------------------------------------------------------
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Residues in contact with ALA 47 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     43B  ALA      3.2    12.5    +      -       -      +
     44B  ILE*     3.0    10.5    +      -       -      +
     46B  SER*     1.3    72.8    -      -       -      +
     48B  VAL*     1.3    65.9    +      -       -      +
     50B  LYS*     3.2    20.0    +      -       -      +
     51B  ALA      5.0     4.3    -      -       -      +
     73B  LEU*     3.7    25.3    -      -       +      +
     76B  LEU*     4.1    19.7    -      -       +      -
     80B  LEU*     5.3     1.6    -      -       +      -
     55C  HIS*     6.1     3.6    -      -       +      +
----------------------------------------------------------
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Residues in contact with VAL 48 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    169A  SER*     3.3    38.3    +      -       -      +
    170A  ALA*     3.8     4.5    -      -       -      +
     44B  ILE*     2.8    36.9    +      -       +      +
     45B  SER*     3.2     7.4    +      -       -      +
     47B  ALA*     1.3    75.9    -      -       -      +
     49B  ARG*     1.3    58.1    +      -       -      +
     50B  LYS*     3.1    18.2    +      -       -      +
     73B  LEU*     4.1    16.1    -      -       +      +
    120B  LEU*     4.0    16.6    -      -       +      -
    126B  ILE*     4.1     7.8    -      -       +      +
    132B  VAL*     4.6     2.0    -      -       +      -
    167B  TYR*     3.9    24.2    -      -       +      -
----------------------------------------------------------
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Residues in contact with ARG 49 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     49A  ARG*     3.1    40.5    -      -       +      +
    168A  GLY      3.9     1.2    +      -       -      -
    169A  SER      3.1    17.6    +      -       -      +
    170A  ALA*     4.2     7.7    -      -       -      +
    171A  THR      5.1     0.9    +      -       -      -
    186A  LEU      3.9     3.1    -      -       -      +
    188A  PRO*     3.4    25.6    -      -       +      +
     45B  SER*     3.1    26.3    +      -       -      +
     46B  SER*     3.7     7.6    -      -       -      +
     47B  ALA      3.3     0.2    -      -       -      -
     48B  VAL*     1.3    73.9    -      -       -      +
     50B  LYS*     1.3    69.9    +      -       -      +
     51B  ALA*     3.4     0.6    +      -       +      -
    167B  TYR*     3.6    19.3    -      -       -      +
    168B  GLY      2.6    32.3    +      -       -      -
    169B  SER      3.8     5.5    -      -       -      -
    170B  ALA*     3.9     4.8    -      -       -      +
    171B  THR*     2.6    30.0    +      -       -      -
----------------------------------------------------------
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Residues in contact with LYS 50 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    170A  ALA*     4.0     8.2    -      -       +      +
    185A  MET*     3.8    34.5    -      -       +      +
    186A  LEU      4.5     1.3    -      -       -      +
    187A  ASP*     3.8     5.2    -      -       -      +
    188A  PRO*     4.0     2.1    -      -       -      +
     46B  SER      3.5     0.2    +      -       -      -
     47B  ALA      3.2    12.2    +      -       -      +
     48B  VAL      3.1    10.6    +      -       -      +
     49B  ARG*     1.3    81.3    -      -       -      +
     51B  ALA*     1.3    58.8    +      -       -      +
     52B  GLY      2.8    10.6    +      -       -      -
     53B  ILE*     3.1    47.5    +      -       +      +
     56B  LEU*     6.2     0.7    -      -       -      -
     73B  LEU*     3.6    27.3    -      -       -      +
    126B  ILE*     4.4    11.7    +      -       -      +
    129B  LEU*     6.2     1.6    -      -       -      +
----------------------------------------------------------
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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