Contacts of the helix formed by residues 121 - 149 (chain A) in PDB entry 5C5B


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 ARG 121 (chain A).
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    117A  GLN*     2.9    53.0    +      -       +      +
    120A  GLU*     1.3    80.6    -      -       -      +
    122A  ASP*     1.3    86.9    +      -       -      +
    123A  LEU      3.7     0.4    -      -       -      -
    124A  LYS*     4.0     0.7    -      -       -      +
    125A  GLU*     3.0    35.7    +      -       +      +
    191A  LYS*     4.5     9.4    -      -       -      +
----------------------------------------------------------
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Residues in contact with ASP 122 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    117A  GLN      3.5     2.8    -      -       -      +
    118A  PHE*     3.3    46.6    +      -       +      +
    121A  ARG*     1.3    99.3    +      -       -      +
    123A  LEU*     1.3    60.9    +      -       -      +
    125A  GLU*     3.3     9.9    +      -       -      +
    126A  ILE*     2.9    34.5    +      -       +      +
    188A  LEU*     5.0     3.8    -      -       +      -
    191A  LYS*     2.5    43.6    +      -       +      +
----------------------------------------------------------
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Residues in contact with LEU 123 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     30A  ALA*     4.8     4.9    -      -       +      +
     33A  ILE*     4.6     5.6    -      -       +      -
     34A  SER*     3.9    28.3    -      -       -      +
     37A  MET*     4.6     3.6    -      -       +      -
    118A  PHE*     3.1    45.3    +      -       +      +
    119A  LYS*     3.5    47.3    -      -       +      +
    122A  ASP*     1.3    78.2    -      -       -      +
    124A  LYS*     1.3    59.6    -      -       -      +
    126A  ILE*     3.2    10.7    +      -       +      +
    127A  LEU*     2.9    28.9    +      -       -      +
    188A  LEU*     4.5    15.7    -      -       +      -
----------------------------------------------------------
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Residues in contact with LYS 124 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    119A  LYS*     3.4    27.9    +      -       -      +
    120A  GLU*     3.8    37.5    -      -       -      +
    121A  ARG      3.8     1.1    +      -       -      +
    122A  ASP      3.3     0.4    -      -       -      -
    123A  LEU*     1.3    80.1    -      -       +      +
    125A  GLU*     1.3    57.7    +      -       -      +
    127A  LEU*     3.3    22.1    +      -       +      +
    128A  THR*     2.8    33.6    +      -       -      +
----------------------------------------------------------
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Residues in contact with GLU 125 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    121A  ARG*     3.0    24.7    +      -       +      +
    122A  ASP*     3.7    13.2    -      -       -      +
    124A  LYS*     1.3    73.3    -      -       -      +
    126A  ILE*     1.3    64.0    +      -       +      +
    128A  THR*     3.2     6.9    +      -       -      -
    129A  LEU*     2.9    54.8    +      -       +      +
    184A  ALA*     5.2     7.0    -      -       +      +
    191A  LYS*     4.9     5.9    +      -       -      -
----------------------------------------------------------
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Residues in contact with ILE 126 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     30A  ALA*     4.8    11.9    -      -       +      -
    122A  ASP*     2.9    21.8    +      -       +      +
    123A  LEU*     3.3    13.0    -      -       +      +
    125A  GLU*     1.3    77.4    -      -       +      +
    127A  LEU*     1.3    58.4    +      -       -      +
    129A  LEU*     4.0     2.6    -      -       -      -
    130A  LYS*     2.9    32.7    +      -       +      +
    181A  TYR*     3.9    11.6    -      -       +      +
    184A  ALA*     3.6    43.3    -      -       +      +
    185A  LEU*     4.0    26.5    -      -       +      +
    188A  LEU*     4.3    19.7    -      -       +      -
----------------------------------------------------------
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Residues in contact with LEU 127 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    123A  LEU      2.9    12.7    +      -       -      +
    124A  LYS*     3.7    28.3    -      -       +      +
    126A  ILE*     1.3    77.5    -      -       -      +
    128A  THR*     1.3    58.4    +      -       -      +
    130A  LYS*     3.3    15.6    -      -       +      +
    131A  GLU*     3.0    48.9    +      -       +      +
----------------------------------------------------------
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Residues in contact with THR 128 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    124A  LYS*     2.8    25.1    +      -       -      +
    125A  GLU*     3.4     9.0    -      -       -      -
    127A  LEU*     1.3    78.7    -      -       -      +
    129A  LEU*     1.3    65.2    +      -       +      +
    131A  GLU*     3.1     5.7    +      -       -      +
    132A  VAL*     2.9    43.5    +      -       +      +
----------------------------------------------------------
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Residues in contact with LEU 129 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    125A  GLU*     2.9    50.8    +      -       +      +
    126A  ILE*     4.0     3.4    -      -       -      +
    128A  THR*     1.3    82.6    -      -       +      +
    130A  LYS*     1.3    57.4    +      -       -      +
    132A  VAL*     3.7     8.6    -      -       +      +
    133A  PHE*     2.9    31.0    +      -       -      +
    177A  THR*     4.8     2.4    -      -       -      +
    180A  HIS*     3.4    44.2    -      -       +      +
    181A  TYR*     4.4    13.7    -      -       +      +
    184A  ALA*     3.8    15.5    -      -       +      -
----------------------------------------------------------
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Residues in contact with LYS 130 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     27A  GLU*     3.2    22.8    +      -       +      +
     31A  THR*     5.1     7.3    +      -       -      -
    126A  ILE*     2.9    21.2    +      -       +      +
    127A  LEU*     3.3    16.4    -      -       +      +
    129A  LEU*     1.3    77.5    -      -       -      +
    131A  GLU*     1.3    67.9    +      -       +      +
    133A  PHE*     3.2     6.1    +      -       +      +
    134A  GLN*     2.9    54.6    +      -       +      +
    181A  TYR*     3.3    36.0    -      -       +      +
----------------------------------------------------------
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Residues in contact with GLU 131 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    127A  LEU*     3.0    35.6    +      -       +      +
    128A  THR*     3.1     4.0    +      -       -      +
    130A  LYS*     1.3    82.4    -      -       +      +
    132A  VAL*     1.3    61.5    +      -       +      +
    134A  GLN*     3.5    28.8    +      -       -      +
    135A  ILE*     2.9    37.1    +      -       +      +
----------------------------------------------------------
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Residues in contact with VAL 132 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    128A  THR*     2.9    34.6    +      -       +      +
    129A  LEU*     3.7     7.2    -      -       +      +
    131A  GLU*     1.3    77.8    -      -       -      +
    133A  PHE*     1.3    57.5    +      -       -      +
    135A  ILE*     3.3     7.0    +      -       -      +
    136A  ALA*     2.9    28.1    +      -       -      +
    173A  LYS*     4.7    14.0    +      -       -      +
    177A  THR*     3.6    23.8    -      -       +      -
----------------------------------------------------------
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Residues in contact with PHE 133 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     20A  ARG*     3.8    35.2    -      -       -      -
     23A  LEU*     3.6    24.9    -      -       +      -
     27A  GLU*     5.2     2.0    -      -       -      -
    129A  LEU      2.9    18.1    +      -       -      +
    130A  LYS      3.4     5.2    -      -       -      +
    132A  VAL*     1.3    77.3    -      -       -      +
    134A  GLN*     1.3    65.4    +      -       +      +
    136A  ALA*     3.4     1.0    +      -       -      +
    137A  SER*     2.9    28.9    +      -       -      -
    174A  GLN*     4.4     6.7    -      -       +      -
    177A  THR*     3.8    21.0    -      -       -      +
    178A  MET*     3.5    48.5    -      -       +      -
    181A  TYR*     3.7    23.8    -      +       +      -
----------------------------------------------------------
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Residues in contact with GLN 134 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     27A  GLU*     5.0     1.4    +      -       -      -
    130A  LYS*     2.9    50.1    +      -       +      +
    131A  GLU*     3.5    29.3    +      -       -      +
    132A  VAL      3.3     0.2    -      -       -      -
    133A  PHE*     1.3    83.8    -      -       +      +
    135A  ILE*     1.3    57.3    +      -       +      +
    137A  SER*     3.2     7.7    +      -       -      -
    138A  ASN*     3.0    38.8    +      -       -      +
----------------------------------------------------------
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Residues in contact with ILE 135 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    131A  GLU*     2.9    23.3    +      -       +      +
    132A  VAL*     3.3     6.7    +      -       -      +
    134A  GLN*     1.3    76.4    -      -       +      +
    136A  ALA*     1.3    62.7    +      -       -      +
    138A  ASN*     3.2    10.8    +      -       -      +
    139A  ASP*     2.9    38.7    +      -       -      +
    173A  LYS*     5.3     8.5    -      -       -      +
----------------------------------------------------------
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Residues in contact with ALA 136 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    132A  VAL      2.9    17.2    +      -       -      +
    133A  PHE      3.7     1.1    -      -       -      +
    135A  ILE*     1.3    77.3    -      -       -      +
    137A  SER*     1.3    57.3    +      -       -      +
    139A  ASP*     3.4     9.3    +      -       -      +
    140A  HIS*     2.9    28.8    +      -       -      +
    170A  SER      4.3     4.6    -      -       -      +
    173A  LYS*     4.2    16.1    -      -       +      +
    174A  GLN*     4.0    16.8    -      -       -      +
    177A  THR*     3.6    28.0    -      -       +      +
----------------------------------------------------------
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Residues in contact with SER 137 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     20A  ARG*     3.4    24.1    +      -       -      -
    133A  PHE*     2.9    24.6    +      -       -      -
    134A  GLN*     3.4     8.7    -      -       -      -
    135A  ILE      3.2     0.2    -      -       -      -
    136A  ALA*     1.3    76.3    -      -       -      +
    138A  ASN*     1.3    65.9    +      -       -      +
    140A  HIS*     3.2     3.6    +      -       -      +
    141A  ASP*     2.9    35.9    +      -       -      +
    174A  GLN*     3.4    20.5    +      -       -      +
    314B  ARG*     3.8     3.8    +      -       -      -
----------------------------------------------------------
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Residues in contact with ASN 138 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    134A  GLN*     3.0    25.4    +      -       -      +
    135A  ILE*     3.6    10.9    -      -       -      +
    137A  SER*     1.3    78.9    +      -       -      +
    139A  ASP*     1.3    65.8    +      -       -      +
    141A  ASP*     3.2    15.3    +      -       -      +
    142A  ALA*     3.0    23.4    +      -       -      +
----------------------------------------------------------
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Residues in contact with ASP 139 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    135A  ILE*     2.9    35.7    +      -       -      +
    136A  ALA*     3.6     8.4    -      -       -      +
    138A  ASN*     1.3    78.8    -      -       -      +
    140A  HIS*     1.3    57.3    +      -       -      +
    142A  ALA*     3.3     8.2    +      -       -      +
    143A  ALA*     2.9    28.1    +      -       -      +
    170A  SER*     4.0    10.7    -      -       -      -
    173A  LYS*     5.5     4.2    +      -       -      +
----------------------------------------------------------
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Residues in contact with HIS 140 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     15A  ASP*     5.7     1.1    -      -       -      -
    136A  ALA      2.9    18.4    +      -       -      +
    137A  SER      3.2     4.0    +      -       -      +
    139A  ASP*     1.3    71.9    -      -       -      +
    141A  ASP*     1.3    74.3    +      -       -      +
    143A  ALA*     3.2     1.0    +      -       -      +
    144A  ILE*     2.9    28.0    +      -       +      +
    167A  VAL*     4.1     4.9    -      -       +      -
    170A  SER*     3.3    22.8    -      -       -      +
    171A  ARG*     3.0    57.4    +      -       +      +
    174A  GLN*     3.3    30.1    +      -       -      +
    299B  ARG*     4.2    26.6    +      -       -      -
    314B  ARG*     5.4     1.2    +      -       -      -
----------------------------------------------------------
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Residues in contact with ASP 141 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    137A  SER*     2.9    25.3    +      -       -      +
    138A  ASN*     3.2    16.5    +      -       -      +
    140A  HIS*     1.3    81.9    +      -       -      +
    142A  ALA*     1.3    63.1    +      -       -      +
    144A  ILE*     3.3     7.8    -      -       -      +
    145A  ASN*     3.0    36.9    +      -       -      +
    174A  GLN*     4.9     0.3    -      -       -      +
    299B  ARG*     4.5     5.0    +      -       -      -
    314B  ARG*     3.0    36.9    +      -       -      -
----------------------------------------------------------
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Residues in contact with ALA 142 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    138A  ASN      3.0    13.3    +      -       -      +
    139A  ASP*     3.5    11.0    -      -       -      +
    141A  ASP*     1.3    76.3    -      -       -      +
    143A  ALA*     1.3    61.8    +      -       -      +
    145A  ASN*     3.2    11.7    +      -       -      +
    146A  ARG*     3.0    35.0    +      -       -      +
----------------------------------------------------------
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Residues in contact with ALA 143 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    139A  ASP      2.9    12.8    +      -       -      +
    140A  HIS      3.5     2.0    -      -       -      +
    142A  ALA*     1.3    76.7    -      -       -      +
    144A  ILE*     1.3    56.9    +      -       -      +
    146A  ARG*     3.2     8.4    +      -       -      +
    147A  TYR      2.9    22.2    +      -       -      -
    163A  VAL*     4.3     2.0    -      -       -      +
    166A  ASP*     4.1     9.6    -      -       +      +
    167A  VAL*     3.3    27.0    -      -       +      +
    170A  SER*     3.2    29.2    -      -       -      +
----------------------------------------------------------
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Residues in contact with ILE 144 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    140A  HIS*     2.9    24.2    +      -       +      +
    141A  ASP*     3.3    16.4    -      -       -      +
    143A  ALA*     1.3    75.1    -      -       -      +
    145A  ASN*     1.3    67.0    +      -       -      +
    147A  TYR*     3.5    14.0    -      -       +      +
    148A  SER*     2.9    37.7    +      -       -      +
    167A  VAL*     3.9     5.3    -      -       +      +
    171A  ARG*     4.0    20.6    -      -       -      +
    299B  ARG*     4.0    39.7    -      -       -      +
    358B  GLU*     4.2    10.1    -      -       +      +
----------------------------------------------------------
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Residues in contact with ASN 145 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    141A  ASP*     3.0    36.6    +      -       -      +
    142A  ALA*     3.2     8.9    +      -       -      +
    144A  ILE*     1.3    81.3    -      -       -      +
    146A  ARG*     1.3    59.8    +      -       -      +
    148A  SER*     3.2     9.5    +      -       -      -
    149A  ARG*     3.0    36.5    +      -       -      +
    285B  ASN*     5.3     2.8    +      -       -      +
    299B  ARG*     5.0    11.6    -      -       -      +
----------------------------------------------------------
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Residues in contact with ARG 146 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    142A  ALA*     3.0    21.6    +      -       -      +
    143A  ALA*     3.7     8.5    -      -       -      +
    145A  ASN*     1.3    76.1    -      -       -      +
    147A  TYR*     1.3    62.5    +      -       -      +
    149A  ARG*     3.5    19.9    +      -       +      +
    150A  LEU*     3.6    12.0    +      -       -      +
    163A  VAL*     3.7    22.1    -      -       +      +
----------------------------------------------------------
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Residues in contact with TYR 147 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    143A  ALA      2.9     5.5    +      -       -      -
    144A  ILE*     3.5    14.8    -      -       +      +
    145A  ASN      3.1     0.2    -      -       -      -
    146A  ARG*     1.3    76.0    -      -       -      +
    148A  SER*     1.3    69.4    +      -       -      +
    150A  LEU*     3.2    30.3    +      -       +      +
    160A  LYS*     5.9     0.4    -      -       +      -
    163A  VAL*     3.5     7.4    -      -       +      +
    164A  THR*     3.7    35.0    -      -       +      -
    167A  VAL*     3.6    20.9    -      -       +      -
    264B  PRO*     3.8    22.4    +      -       +      +
    265B  ASP*     3.6    13.0    -      -       -      +
    339B  ARG*     3.2    39.0    +      -       -      +
    340B  TYR*     5.6     0.2    -      +       -      -
    358B  GLU*     2.9    46.2    +      -       +      -
----------------------------------------------------------
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Residues in contact with SER 148 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    144A  ILE*     2.9    22.8    +      -       -      +
    145A  ASN*     3.5    11.6    +      -       -      -
    147A  TYR*     1.3    82.0    -      -       -      +
    149A  ARG*     1.3    61.7    +      -       -      +
    150A  LEU      3.1     4.2    +      -       -      +
    285B  ASN*     2.7    32.0    +      -       -      -
    299B  ARG*     5.9     0.3    -      -       -      -
    338B  ARG*     3.5    24.7    +      -       -      +
    339B  ARG*     4.9     0.9    +      -       -      +
    356B  GLN*     3.2    25.2    +      -       -      +
    358B  GLU*     6.2     0.2    -      -       -      +
----------------------------------------------------------
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Residues in contact with ARG 149 (chain A). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    145A  ASN*     3.0    24.6    +      -       -      +
    146A  ARG*     3.9    15.0    -      -       +      +
    147A  TYR      3.2     0.6    -      -       -      -
    148A  SER*     1.3    73.1    -      -       -      +
    150A  LEU*     1.3    67.4    +      -       -      +
    151A  SER*     3.5     2.3    +      -       -      -
    338B  ARG*     3.9    26.8    -      -       -      +
----------------------------------------------------------
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A short description of the analytical approach
The contact analysis used in this page is based upon the approach developed in: Sobolev V., Wade R.C., Vriend G. and Edelman M. PROTEINS (1996) 25, 120-129. Contact legitimacy depends on the hydrophobic-hydrophilic properties of the contacting atoms. In order to define it, for each inter-atomic contact, eight atom classes have been introduced:


   I  Hydrophilic      - N and O that can donate and accept hydrogen bonds
                         (e.g., oxygen of hydroxyl group of Ser. or Thr)
  II  Acceptor         - N or O that can only accept a hydrogen bond
 III  Donor            - N that can only donate a hydrogen bond
  IV  Hydrophobic      - Cl, Br, I and all C atoms that are not in
                         aromatic rings and do not have a covalent bond to
                         a N or O atom
   V  Aromatic         - C in aromatic rings irrespective of any other 
                         bonds formed by the atom
  VI  Neutral          - C atoms that have a covalent bond to at least one
                         atom of class I or two or more atoms from class II
                         or III; atoms; S, F, P, and metal atoms in all cases
 VII  Neutral-donor    - C atoms that have a covalent bond with only one
                         atom of class III
VIII  Neutral-acceptor - C atoms that have a covalent bond with only 
                         one atom of class II
For each pair of contacts the state of legitimacy is shown below:

Legend:
+, legitimate
-, illegitimate
------------------------------------------------------------
  Atomic class           I  II  III   IV   V   VI  VII  VIII
------------------------------------------------------------
   I  (Hydrophilic)      +   +    +    -   +   +    +    +
  II  (Acceptor)         +   -    +    -   +   +    +    -
 III  (Donor)            +   +    -    -   +   +    -    +
  IV  (Hydrophobic)      -   -    -    +   +   +    +    +
   V  (Aromatic)         +   +    +    +   +   +    +    +
  VI  (Neutral)          +   +    +    +   +   +    +    +
 VII  (Neutral-donor)    +   +    -    +   +   +    -    +
VIII  (Neutral-acceptor) +   -    +    +   +   +    +    -
------------------------------------------------------------
Warning!
Atom classes for heterogroups are automatically assigned based on the atomic coordinates. However, in three cases (see below) the automatic assignment is currently ambiguous. In these cases, the user is advised to manually analyse the full list of contacts using LPC software.
1. Carbon atoms belonging to a 4-, 5- or 6-member ring are 
   considered "aromatic" (Class V) if the ring is approximately
   planar, and "hydrophobic" (Class IV) or "neutral" (Classes
   VI, VII, VIII) if the ring is non-planar.
2. The oxygen atom of a carbonyl or hydroxy group is considered
   "hydroxy" (Class I) if the CO bond is longer than 1.29 Å, and
   "carbonyl" (Class II) if shorter.
3. All nitrogen atoms are considered "hydrophilic" (Class I).

Please E-mail any questions and/or suggestions concerning this page to Vladimir.Sobolev@weizmann.ac.il