Contacts of the helix formed by residues 168 - 187 (chain A) in PDB entry 1XAI


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 PRO 168 (chain A).
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     45A  TYR*     4.5    11.7    -      -       +      +
    166A  THR      3.5     8.7    -      -       -      +
    167A  LEU*     1.3    91.2    -      -       +      +
    169A  PHE*     1.3    66.1    +      -       -      +
    170A  LYS*     4.4     8.5    -      -       +      +
    171A  GLN*     3.1    32.7    +      -       +      +
    172A  ILE*     3.1    10.3    +      -       -      +
----------------------------------------------------------
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Residues in contact with PHE 169 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    167A  LEU      4.0     0.2    +      -       -      -
    168A  PRO*     1.3    72.9    -      -       -      +
    170A  LYS*     1.3    58.7    +      -       -      +
    172A  ILE*     2.8    29.6    +      -       +      +
    173A  LEU*     2.9    45.4    +      -       +      +
    201A  ARG*     3.4    42.8    -      -       +      +
    204A  LEU*     3.5    15.3    -      -       +      -
    205A  GLN*     3.3    58.8    -      -       +      +
    291A  LEU      3.1    28.3    -      -       -      -
    292A  GLY*     4.4     0.7    -      -       -      -
----------------------------------------------------------
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Residues in contact with LYS 170 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    168A  PRO*     3.3     5.8    -      -       +      +
    169A  PHE*     1.3    77.0    -      -       -      +
    171A  GLN*     1.3    74.5    +      -       +      +
    173A  LEU*     4.7     5.6    -      -       -      -
    174A  SER*     3.3     5.4    +      -       -      -
    255A  PRO*     3.8    24.7    -      -       +      -
    258A  HIS*     2.9    44.1    -      -       +      +
----------------------------------------------------------
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Residues in contact with GLN 171 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    125A  THR*     4.6     9.6    +      -       -      +
    126A  ILE*     4.5     5.5    -      -       -      +
    167A  LEU*     4.2    20.4    -      -       +      -
    168A  PRO*     3.1    29.7    +      -       +      +
    169A  PHE      3.0     0.8    -      -       -      -
    170A  LYS*     1.3    99.5    +      -       +      +
    172A  ILE*     1.3    59.4    +      -       -      +
    173A  LEU      3.3     0.9    -      -       -      -
    174A  SER*     3.5    15.3    +      -       -      -
    175A  GLY*     2.6    31.0    +      -       -      -
    255A  PRO*     5.1     5.1    -      -       -      +
----------------------------------------------------------
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Residues in contact with ILE 172 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    126A  ILE*     3.7    24.1    -      -       +      +
    167A  LEU*     3.8    27.6    -      -       +      +
    168A  PRO      3.1    14.5    +      -       -      +
    169A  PHE*     2.8    21.9    +      -       +      +
    171A  GLN*     1.3    73.8    -      -       -      +
    173A  LEU*     1.3    56.2    +      -       -      +
    175A  GLY*     3.3     0.5    +      -       -      -
    176A  TYR*     2.6    38.9    +      -       -      +
    204A  LEU*     3.3    38.1    -      -       +      +
    205A  GLN*     5.2     3.8    -      -       -      +
    207A  LEU*     3.5    32.3    -      -       +      -
----------------------------------------------------------
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Residues in contact with LEU 173 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    169A  PHE*     2.9    34.7    +      -       +      +
    170A  LYS*     4.7     4.3    -      -       -      -
    172A  ILE*     1.3    80.9    -      -       -      +
    174A  SER*     1.3    65.0    +      -       -      +
    176A  TYR*     4.1     2.2    -      -       -      -
    177A  ALA*     3.2     5.2    +      -       -      +
    204A  LEU*     3.4    16.8    -      -       +      -
    258A  HIS*     3.9    18.4    -      -       +      +
    291A  LEU      3.2    26.0    -      -       -      +
    292A  GLY      3.5    21.8    -      -       -      +
    293A  TYR*     2.3    60.2    +      -       +      +
    294A  PRO*     4.5     2.9    -      -       +      -
----------------------------------------------------------
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Residues in contact with SER 174 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    127A  LEU*     4.0    12.8    -      -       -      +
    170A  LYS      3.3    18.8    +      -       -      -
    171A  GLN*     3.5    19.0    +      -       -      -
    172A  ILE      3.2     0.4    -      -       -      -
    173A  LEU*     1.3    80.3    -      -       -      +
    175A  GLY*     1.3    62.6    +      -       -      +
    177A  ALA*     3.3     3.8    +      -       -      +
    178A  GLU      4.3     0.9    +      -       -      -
    255A  PRO*     3.5    11.5    -      -       -      +
    256A  HIS      3.8     2.8    +      -       -      -
    257A  GLY*     3.0    41.4    +      -       -      -
    258A  HIS*     3.5    14.1    -      -       -      -
----------------------------------------------------------
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Residues in contact with GLY 175 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    126A  ILE*     3.6    17.2    -      -       -      +
    127A  LEU*     3.5    32.8    -      -       -      +
    129A  HIS*     4.4     0.2    -      -       -      -
    171A  GLN      2.6    21.1    +      -       -      -
    172A  ILE      3.7     0.2    -      -       -      -
    174A  SER*     1.3    73.3    -      -       -      +
    176A  TYR*     1.3    61.0    +      -       -      +
    178A  GLU*     3.1    17.3    +      -       -      +
    179A  VAL*     3.4     7.1    +      -       -      +
----------------------------------------------------------
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Residues in contact with TYR 176 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    126A  ILE*     4.0     2.8    -      -       -      +
    172A  ILE      2.6    24.7    +      -       -      +
    173A  LEU*     3.2     5.8    +      -       -      +
    175A  GLY*     1.3    72.6    -      -       -      +
    177A  ALA*     1.3    54.8    +      -       -      +
    179A  VAL*     3.1    10.9    +      -       +      -
    180A  TYR*     2.7    57.3    +      +       +      +
    194A  ILE*     3.4    33.4    -      -       +      +
    198A  PHE*     3.6    27.9    -      +       +      +
    204A  LEU*     3.9    12.3    -      -       +      -
    210A  MET*     3.8    19.1    -      -       +      -
    261A  MET*     5.5     1.3    -      -       -      -
    287A  TYR*     2.8    21.5    +      -       -      -
    291A  LEU*     3.2    34.5    -      -       +      -
    293A  TYR*     3.7     8.3    -      +       -      +
----------------------------------------------------------
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Residues in contact with ALA 177 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    173A  LEU      3.2     6.8    +      -       -      +
    174A  SER      3.5     0.4    -      -       -      +
    175A  GLY      3.1     1.0    -      -       -      -
    176A  TYR*     1.3    76.8    -      -       -      +
    178A  GLU*     1.3    59.9    +      -       +      +
    181A  LYS*     3.2    22.7    +      -       -      +
    257A  GLY*     3.1    45.3    -      -       -      +
    260A  VAL*     4.0     8.7    -      -       +      +
    261A  MET*     3.1    34.8    -      -       +      +
    293A  TYR*     3.5     1.1    +      -       -      -
----------------------------------------------------------
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Residues in contact with GLU 178 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    127A  LEU*     4.1    21.3    -      -       +      -
    129A  HIS*     3.3    21.5    -      -       +      -
    130A  ASP*     3.3    20.6    -      -       +      +
    174A  SER      4.9     1.3    -      -       -      +
    175A  GLY      3.1     6.9    +      -       -      +
    177A  ALA*     1.3    76.8    -      -       +      +
    179A  VAL*     1.3    66.0    +      -       -      +
    180A  TYR      3.1     1.3    -      -       -      -
    181A  LYS*     3.0    34.6    +      -       -      +
    182A  HIS*     3.1    30.2    +      -       +      -
    242A  HIS*     3.6     3.1    +      -       -      -
    256A  HIS*     3.3    11.3    -      -       -      -
    257A  GLY*     5.7     0.2    -      -       -      -
    260A  VAL*     4.0     5.9    -      -       -      +
    500A  CRB      3.3     0.3    +      -       -      -
    600A   ZN      2.2    32.7    -      -       -      -
----------------------------------------------------------
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Residues in contact with VAL 179 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    126A  ILE*     3.9    16.8    -      -       +      -
    129A  HIS*     3.8    23.8    -      -       +      +
    175A  GLY      3.8     9.6    -      -       -      +
    176A  TYR*     3.1    17.6    +      -       +      +
    178A  GLU*     1.3    77.6    -      -       -      +
    180A  TYR*     1.3    61.8    +      -       -      +
    182A  HIS*     3.8     5.2    +      -       -      +
    183A  ALA*     3.5    17.3    +      -       -      +
    194A  ILE*     3.7    21.2    -      -       +      +
    210A  MET*     4.5     5.6    -      -       -      -
    213A  TYR*     3.3    31.9    -      -       +      +
    214A  ILE*     4.3    12.1    -      -       +      -
    217A  GLY*     5.7     0.6    -      -       -      -
----------------------------------------------------------
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Residues in contact with TYR 180 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    176A  TYR*     2.7    41.6    +      +       +      +
    177A  ALA      4.0     3.6    -      -       -      +
    179A  VAL*     1.3    77.2    -      -       -      +
    181A  LYS*     1.3    57.8    +      -       -      +
    183A  ALA*     3.0     8.0    -      -       -      +
    184A  LEU*     3.0    51.5    +      -       +      +
    191A  THR*     3.7    10.9    -      -       +      +
    194A  ILE*     4.0    12.5    -      -       +      +
    195A  GLU*     3.0    21.3    +      -       +      -
    261A  MET*     3.6    28.0    -      -       +      -
    264A  ILE*     4.9     4.7    -      -       +      -
    284A  TYR*     2.9    37.3    -      +       -      -
    287A  TYR*     3.7    24.2    -      +       -      -
    288A  LEU*     5.7     1.6    -      -       +      -
----------------------------------------------------------
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Residues in contact with LYS 181 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    130A  ASP*     4.4     0.4    +      -       -      -
    177A  ALA      3.2    20.3    +      -       -      +
    178A  GLU*     3.0    25.2    +      -       -      +
    180A  TYR*     1.3    74.5    -      -       -      +
    182A  HIS*     1.3    89.2    +      -       -      +
    184A  LEU*     3.3    13.4    +      -       -      +
    185A  LEU*     3.1    24.5    +      -       +      +
    238A  LEU*     2.6    39.6    +      -       -      +
    240A  LEU*     3.6    31.2    -      -       +      +
    242A  HIS*     3.6    16.1    -      -       +      -
    260A  VAL*     5.0     0.9    -      -       +      -
    264A  ILE*     4.3     7.6    -      -       +      -
    500A  CRB      3.4    15.0    +      -       -      +
----------------------------------------------------------
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Residues in contact with HIS 182 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    129A  HIS*     3.2    36.1    +      +       -      -
    130A  ASP*     4.0    22.1    +      -       +      -
    178A  GLU      3.1    11.3    +      -       -      +
    179A  VAL*     4.0     5.1    -      -       -      +
    181A  LYS*     1.3    96.9    +      -       -      +
    183A  ALA*     1.3    51.7    +      -       -      +
    185A  LEU*     3.3    15.6    +      -       +      +
    186A  ASN*     2.8    32.7    +      -       -      +
    217A  GLY*     3.4    31.3    +      -       -      -
    220A  THR*     4.0    20.2    -      -       +      +
    221A  LYS*     4.3    14.0    -      -       +      +
    238A  LEU*     4.6     9.7    -      -       +      +
----------------------------------------------------------
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Residues in contact with ALA 183 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    179A  VAL      3.5    11.2    +      -       -      +
    180A  TYR*     3.0    15.0    -      -       +      +
    181A  LYS      3.0     0.2    -      -       -      -
    182A  HIS*     1.3    76.1    -      -       -      +
    184A  LEU*     1.3    56.0    +      -       -      +
    185A  LEU      2.9     1.6    -      -       -      -
    186A  ASN*     2.7    28.0    +      -       -      +
    187A  GLY      3.3    10.6    +      -       -      +
    190A  ALA*     4.0    11.4    -      -       +      +
    191A  THR*     3.3    10.2    +      -       -      -
    194A  ILE*     3.9    29.6    -      -       +      -
    216A  LYS*     6.0     1.8    -      -       -      +
----------------------------------------------------------
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Residues in contact with LEU 184 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    180A  TYR*     3.0    47.2    +      -       +      +
    181A  LYS*     3.3     9.8    +      -       -      +
    183A  ALA*     1.3    75.1    -      -       -      +
    185A  LEU*     1.3    60.2    +      -       -      +
    187A  GLY*     3.7     2.8    +      -       -      -
    191A  THR*     3.2    14.7    +      -       +      +
    240A  LEU*     4.2    20.9    -      -       +      -
    264A  ILE*     3.6    35.0    -      -       +      -
    268A  PHE*     3.7    24.0    -      -       +      -
    284A  TYR*     4.2     1.6    -      -       +      -
    326A  MET*     2.9    27.6    -      -       +      +
    329A  PHE*     3.6    26.0    -      -       +      -
----------------------------------------------------------
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Residues in contact with LEU 185 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    181A  LYS*     3.1    29.3    +      -       +      +
    182A  HIS*     3.3    16.6    -      -       +      +
    183A  ALA      2.9     0.6    -      -       -      -
    184A  LEU*     1.3    79.1    -      -       -      +
    186A  ASN*     1.3    59.1    +      -       -      +
    187A  GLY      3.2     3.8    +      -       -      -
    220A  THR*     5.1     7.9    -      -       +      -
    224A  ILE*     6.1     2.9    -      -       +      -
    237A  PHE*     3.4    32.3    -      -       +      +
    238A  LEU*     4.5    11.7    -      -       +      -
    240A  LEU*     2.9    37.0    -      -       +      -
    326A  MET*     4.7     1.8    -      -       +      -
    330A  GLY*     5.5     4.0    +      -       -      -
    332A  ILE*     4.5    25.4    -      -       +      +
----------------------------------------------------------
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Residues in contact with ASN 186 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    182A  HIS      2.8    11.9    +      -       -      +
    183A  ALA*     2.7    14.0    +      -       -      +
    185A  LEU*     1.3    78.9    -      -       -      +
    187A  GLY*     1.3    55.8    +      -       -      -
    189A  SER*     5.7     1.2    -      -       -      -
    190A  ALA*     3.6    22.0    +      -       +      +
    216A  LYS*     3.6    25.3    +      -       -      +
    220A  THR*     3.6    24.5    +      -       +      +
----------------------------------------------------------
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Residues in contact with GLY 187 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    183A  ALA      3.3     1.3    +      -       -      +
    184A  LEU      3.7     2.5    +      -       -      -
    185A  LEU      3.2     5.4    +      -       -      -
    186A  ASN*     1.3    80.3    -      -       -      +
    188A  GLU*     1.3    64.9    +      -       -      -
    189A  SER*     3.1     5.0    +      -       -      -
    190A  ALA      3.5     1.0    +      -       -      -
    191A  THR*     3.1    26.0    +      -       -      -
    329A  PHE*     3.5    20.2    -      -       -      -
    330A  GLY*     5.1     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