Contacts of the helix formed by residues 1220 - 1243 (chain N) in PDB entry 2PPB


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 ALA1220 (chain N).
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
   1041M  GLU      3.0    28.7    +      -       -      +
   1042M  ALA*     3.8     6.8    +      -       -      -
   1043M  TYR      5.1     0.4    +      -       -      -
   1106N  VAL*     4.2    12.6    -      -       +      -
   1218N  GLY      3.8     3.4    +      -       -      -
   1219N  GLU*     1.3    70.7    -      -       -      +
   1221N  VAL*     1.3    60.0    +      -       -      +
   1222N  GLY      3.3     2.2    -      -       -      -
   1223N  ILE*     3.4    23.5    -      -       +      +
   1224N  VAL*     3.0    26.3    +      -       -      +
   1462N  LEU*     3.6    11.9    -      -       +      -
   1474N  ALA*     4.7     3.3    -      -       +      +
----------------------------------------------------------
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Residues in contact with VAL1221 (chain N). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
   1105N  ILE*     4.1     8.1    +      -       +      +
   1106N  VAL      5.5     0.2    -      -       -      -
   1107N  VAL*     3.4    29.4    -      -       +      +
   1200N  VAL*     5.6     2.5    -      -       +      -
   1205N  TYR*     3.2    54.3    -      -       +      +
   1215N  VAL*     4.5     0.7    -      -       +      -
   1219N  GLU*     2.5    21.4    +      -       +      +
   1220N  ALA*     1.3    69.8    -      -       -      +
   1222N  GLY*     1.3    59.2    +      -       -      +
   1224N  VAL*     2.9     8.3    -      -       +      +
   1225N  ALA*     2.6    33.8    +      -       +      +
   1370N  ILE*     3.6    21.8    -      -       +      -
----------------------------------------------------------
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Residues in contact with GLY1222 (chain N). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
   1102N  THR*     3.2    38.4    +      -       -      -
   1105N  ILE*     3.0    23.6    +      -       -      -
   1221N  VAL*     1.3    78.7    -      -       -      +
   1223N  ILE*     1.3    57.6    +      -       -      +
   1225N  ALA*     3.3     2.8    +      -       -      +
   1226N  ALA      2.8    23.0    +      -       -      -
   1370N  ILE*     4.2     5.8    -      -       -      -
----------------------------------------------------------
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Residues in contact with ILE1223 (chain N). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
   1038M  TRP*     3.5    47.1    -      -       +      +
   1041M  GLU*     3.9    15.0    -      -       +      +
   1042M  ALA      4.4     3.1    -      -       -      +
   1099N  VAL*     5.3     7.0    -      -       +      +
   1102N  THR*     4.9     0.4    -      -       -      -
   1103N  HIS*     3.7    26.0    -      -       +      +
   1105N  ILE      4.7     0.4    -      -       -      +
   1220N  ALA*     3.4    15.5    -      -       +      +
   1222N  GLY*     1.3    73.2    -      -       -      +
   1224N  VAL*     1.3    59.7    +      -       -      +
   1226N  ALA*     2.7    30.2    +      -       +      +
   1227N  GLN*     2.7    23.5    +      -       +      +
   1462N  LEU*     3.3    31.0    -      -       +      -
----------------------------------------------------------
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Residues in contact with VAL1224 (chain N). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
   1042M  ALA*     4.3    16.1    -      -       +      +
    710N  ARG*     4.4    10.8    -      -       -      +
    772N  PRO*     4.0    25.0    -      -       +      +
   1205N  TYR*     3.4    26.5    -      -       +      +
   1208N  ASP      6.1     0.2    -      -       -      +
   1219N  GLU*     4.3    15.0    -      -       +      +
   1220N  ALA      3.0    13.5    +      -       -      +
   1221N  VAL*     2.9    21.5    -      -       +      +
   1223N  ILE*     1.3    78.8    -      -       -      +
   1225N  ALA*     1.3    69.7    +      -       -      +
   1227N  GLN*     3.7    10.9    +      -       -      +
   1228N  SER*     3.4    19.1    +      -       -      -
   1367N  HIS*     4.1     4.8    +      -       +      -
----------------------------------------------------------
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Residues in contact with ALA1225 (chain N). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
   1221N  VAL*     2.6    21.5    +      -       +      +
   1222N  GLY      3.4     4.7    -      -       -      +
   1223N  ILE      2.8     0.2    +      -       -      -
   1224N  VAL*     1.3    71.7    -      -       -      +
   1226N  ALA*     1.3    66.2    +      -       -      +
   1227N  GLN      2.9     2.1    +      -       -      -
   1228N  SER*     3.0    10.2    +      -       -      -
   1229N  ILE*     3.0    21.0    -      -       +      +
   1367N  HIS*     3.3    40.1    -      -       -      +
   1370N  ILE*     3.9    18.6    -      -       +      -
   1371N  VAL*     5.5     1.3    -      -       +      -
----------------------------------------------------------
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Residues in contact with ALA1226 (chain N). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
   1095N  THR*     4.1     6.2    -      -       -      +
   1098N  LEU*     3.3    30.0    -      -       +      +
   1099N  VAL*     4.2    17.0    -      -       +      +
   1102N  THR*     3.7    14.3    +      -       -      +
   1222N  GLY      2.8    14.1    +      -       -      +
   1223N  ILE*     2.7    16.4    +      -       +      +
   1225N  ALA*     1.3    71.8    -      -       -      +
   1227N  GLN*     1.3    60.3    +      -       +      +
   1229N  ILE*     3.5    11.5    +      -       -      +
   1230N  GLY*     3.3    15.6    +      -       -      -
   1371N  VAL*     5.1     1.1    -      -       -      +
----------------------------------------------------------
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Residues in contact with GLN1227 (chain N). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
   1035M  MET      4.5     2.0    +      -       -      -
   1038M  TRP*     3.1    52.8    +      -       +      +
   1039M  ALA*     3.1    10.5    -      -       -      +
   1042M  ALA*     3.7     5.3    -      -       -      +
    708N  LEU      3.9    16.9    +      -       -      +
    709N  HIS*     4.0     9.4    -      -       +      +
    710N  ARG*     2.8    34.2    +      -       -      +
    772N  PRO*     5.8     1.8    -      -       +      +
   1095N  THR*     5.0     4.9    -      -       +      -
   1223N  ILE*     2.7    28.1    +      -       +      +
   1224N  VAL*     3.9     7.5    -      -       -      +
   1225N  ALA      2.9     0.8    +      -       -      -
   1226N  ALA*     1.3    69.2    -      -       +      +
   1228N  SER*     1.3    54.4    +      -       -      +
   1229N  ILE      2.7    15.8    +      -       -      -
   1230N  GLY*     2.7    12.8    +      -       -      -
   1231N  GLU*     3.2    14.0    +      -       -      +
----------------------------------------------------------
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Residues in contact with SER1228 (chain N). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    709N  HIS*     5.4     2.6    -      -       -      +
    772N  PRO*     4.1     2.4    -      -       -      +
    773N  ALA*     3.5    34.8    -      -       -      +
   1224N  VAL      3.4     8.9    +      -       -      -
   1225N  ALA      3.0     9.2    +      -       -      -
   1227N  GLN*     1.3    76.7    -      -       -      +
   1229N  ILE*     1.3    57.2    +      -       -      +
   1231N  GLU*     3.9     4.8    -      -       -      +
   1232N  PRO*     3.1    24.7    -      -       -      +
   1363N  LEU*     3.8    12.0    -      -       -      +
   1367N  HIS*     3.2    30.7    -      -       -      +
----------------------------------------------------------
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Residues in contact with ILE1229 (chain N). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
   1094N  LEU*     4.9     5.6    -      -       +      +
   1098N  LEU*     3.4    33.4    -      -       +      -
   1225N  ALA      3.0    22.4    -      -       -      +
   1226N  ALA*     3.5     6.3    -      -       -      -
   1227N  GLN      2.7     2.2    +      -       -      -
   1228N  SER*     1.3    76.3    -      -       -      +
   1230N  GLY*     1.3    62.5    +      -       -      +
   1231N  GLU      3.5     0.7    -      -       -      -
   1232N  PRO*     4.0     1.3    -      -       -      -
   1233N  GLY*     3.9     5.0    +      -       -      -
   1263N  PHE*     4.3    19.1    -      -       +      -
   1356N  TYR*     3.1    42.9    +      -       +      +
   1363N  LEU*     4.2    12.8    -      -       +      -
   1367N  HIS*     4.1    21.8    -      -       +      +
   1368N  ILE*     4.7     5.8    -      -       +      +
   1371N  VAL*     4.0    14.1    -      -       +      -
----------------------------------------------------------
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Residues in contact with GLY1230 (chain N). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    708N  LEU*     3.2    10.3    -      -       -      +
   1091N  SER*     3.1    13.5    +      -       -      -
   1094N  LEU*     5.7     2.5    -      -       -      -
   1095N  THR*     2.9    30.5    +      -       -      -
   1098N  LEU*     4.7     0.6    -      -       -      +
   1226N  ALA      3.3     3.8    +      -       -      -
   1227N  GLN      2.7     8.4    +      -       -      -
   1229N  ILE*     1.3    79.8    -      -       -      +
   1231N  GLU*     1.3    62.1    +      -       -      -
   1233N  GLY*     3.8     1.9    +      -       -      -
   1234N  THR*     3.1    15.1    +      -       -      -
----------------------------------------------------------
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Residues in contact with GLU1231 (chain N). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    708N  LEU*     3.3    33.0    -      -       +      +
    709N  HIS*     2.6    38.2    +      -       +      +
    771N  SER*     5.6     1.9    -      -       -      -
    773N  ALA*     3.6    20.4    -      -       -      +
    778N  LEU*     5.1     4.9    -      -       -      +
   1227N  GLN      3.2     9.8    +      -       -      +
   1228N  SER*     3.9     2.8    -      -       -      +
   1230N  GLY*     1.3    73.4    -      -       -      +
   1232N  PRO*     1.4    93.6    -      -       +      +
   1233N  GLY      2.9     2.7    +      -       -      -
   1234N  THR*     3.0    20.8    +      -       -      -
   1235N  GLN*     3.8     3.3    +      -       -      +
----------------------------------------------------------
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Residues in contact with PRO1232 (chain N). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    773N  ALA*     4.9     3.4    -      -       +      -
   1228N  SER      3.1    25.1    -      -       -      +
   1229N  ILE      4.0     2.0    -      -       -      -
   1230N  GLY      4.0     0.4    -      -       -      -
   1231N  GLU*     1.4   112.3    -      -       +      +
   1233N  GLY*     1.3    62.2    +      -       -      +
   1235N  GLN*     3.0     6.9    +      -       +      +
   1236N  LEU*     2.9    31.8    +      -       +      +
   1356N  TYR*     3.9     7.2    -      -       +      -
   1361N  VAL*     3.2    47.3    -      -       +      -
----------------------------------------------------------
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Residues in contact with GLY1233 (chain N). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
   1091N  SER*     3.7     8.7    -      -       -      -
   1094N  LEU*     5.9     2.7    -      -       -      -
   1229N  ILE      3.9    10.2    +      -       -      -
   1230N  GLY      3.8     3.8    +      -       -      -
   1231N  GLU      2.9     2.2    +      -       -      -
   1232N  PRO*     1.3    78.4    -      -       -      +
   1234N  THR*     1.3    55.1    +      -       -      +
   1235N  GLN      2.7    12.0    +      -       -      -
   1236N  LEU*     4.7     2.9    -      -       -      -
   1237N  THR*     3.0    40.7    +      -       -      -
   1256N  LEU*     5.7     2.9    -      -       -      -
   1356N  TYR*     4.3    10.0    -      -       -      -
----------------------------------------------------------
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Residues in contact with THR1234 (chain N). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    708N  LEU*     3.1    26.6    -      -       +      +
   1087N  ARG      5.0     1.8    -      -       -      -
   1088N  THR*     4.3    30.5    -      -       +      +
   1091N  SER*     2.9    25.2    +      -       -      +
   1230N  GLY      3.1     1.9    +      -       -      -
   1231N  GLU      3.0    12.9    +      -       -      -
   1233N  GLY*     1.3    72.4    -      -       -      +
   1235N  GLN*     1.3    56.2    +      -       -      +
   1237N  THR*     5.4     0.2    -      -       -      -
   1238N  MET*     3.2    30.7    -      -       +      +
----------------------------------------------------------
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Residues in contact with GLN1235 (chain N). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
   1231N  GLU      4.7     1.6    -      -       -      +
   1232N  PRO*     3.0    13.1    +      -       +      +
   1233N  GLY      2.7     5.9    +      -       -      -
   1234N  THR*     1.3    77.2    -      -       -      +
   1236N  LEU*     1.3    78.4    +      -       +      +
   1237N  THR      3.4     0.2    -      -       -      -
   1238N  MET*     3.8    16.0    +      -       -      +
   1359N  GLN*     3.4    25.5    +      -       -      +
   1361N  VAL*     4.3     9.5    -      -       +      +
----------------------------------------------------------
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Residues in contact with LEU1236 (chain N). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
   1232N  PRO      2.9    21.5    +      -       -      +
   1233N  GLY*     4.4     1.6    -      -       -      +
   1235N  GLN*     1.3    72.3    -      -       +      +
   1237N  THR*     1.3    60.1    +      -       -      +
   1238N  MET      3.0     5.2    -      -       -      -
   1240N  THR*     2.6    21.8    +      -       -      +
   1355N  VAL*     4.9     2.7    -      -       +      +
   1356N  TYR*     3.4    45.5    -      -       +      +
   1359N  GLN*     2.6    67.7    +      -       +      +
   1361N  VAL*     3.0    39.9    -      -       +      +
----------------------------------------------------------
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Residues in contact with THR1237 (chain N). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
   1087N  ARG*     3.5    27.9    -      -       +      +
   1091N  SER*     5.3     0.4    -      -       -      -
   1233N  GLY*     3.0    24.6    +      -       -      +
   1236N  LEU*     1.3    78.4    -      -       -      +
   1238N  MET*     1.3    61.5    +      -       -      +
   1240N  THR*     4.1     4.5    -      -       -      -
   1241N  PHE*     3.3    23.7    +      -       -      +
   1256N  LEU*     2.9    61.7    +      -       +      +
   1259N  VAL*     4.5     3.5    -      -       -      +
   1355N  VAL*     5.3     2.6    -      -       -      +
   1356N  TYR*     6.0     1.7    -      -       -      -
----------------------------------------------------------
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Residues in contact with MET1238 (chain N). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
   1083N  ASP      5.1     0.2    -      -       -      -
   1084N  THR*     4.0    39.0    -      -       +      +
   1087N  ARG*     3.3    37.7    -      -       +      -
   1088N  THR*     5.0     3.4    -      -       -      +
   1234N  THR*     3.2    27.4    -      -       +      +
   1235N  GLN*     3.8    11.4    +      -       -      +
   1236N  LEU      2.9     1.4    +      -       -      -
   1237N  THR*     1.3    82.7    -      -       -      +
   1239N  ARG*     1.3    63.4    +      -       -      +
   1241N  PHE*     3.9     2.9    -      -       -      +
   1242N  HIS*     3.2    34.7    +      -       +      -
----------------------------------------------------------
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Residues in contact with ARG1239 (chain N). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
   1031N  ASN*     5.8     3.2    -      -       -      +
   1033N  GLN*     5.1    17.0    +      -       -      +
   1236N  LEU      3.2     2.2    +      -       -      -
   1238N  MET*     1.3    77.3    -      -       -      +
   1240N  THR*     1.3    66.4    +      -       -      +
   1242N  HIS*     3.0    17.3    +      -       +      -
   1243N  THR*     3.1    35.1    +      -       +      +
   1253N  THR*     4.2     3.6    -      -       -      +
   1358N  ALA      5.8     1.3    -      -       -      -
   1359N  GLN*     3.0    31.5    -      -       +      +
----------------------------------------------------------
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Residues in contact with THR1240 (chain N). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
   1236N  LEU      2.6    24.4    +      -       -      -
   1237N  THR*     4.5     0.4    -      -       -      -
   1239N  ARG*     1.3    78.2    -      -       -      +
   1241N  PHE*     1.3    59.4    +      -       -      +
   1243N  THR      3.6     1.7    +      -       -      -
   1253N  THR*     2.5    48.3    -      -       -      +
   1254N  GLN*     3.1    32.4    -      -       -      +
   1255N  GLY*     2.8    22.8    +      -       -      -
   1355N  VAL*     3.4    21.5    -      -       +      +
   1359N  GLN*     2.9    17.5    -      -       -      +
----------------------------------------------------------
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Residues in contact with PHE1241 (chain N). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    425M  PHE*     5.3     2.7    -      +       -      -
   1083N  ASP*     3.0    47.3    -      -       +      -
   1087N  ARG*     3.1    43.5    -      -       -      +
   1237N  THR      3.3    18.5    +      -       -      +
   1238N  MET*     3.9     7.0    -      -       +      -
   1239N  ARG      3.2     0.6    -      -       -      -
   1240N  THR*     1.3    77.7    -      -       -      +
   1242N  HIS*     1.3    73.1    +      +       -      +
   1243N  THR*     3.5     2.6    +      -       -      -
   1255N  GLY*     3.5     7.9    -      -       -      +
   1257N  PRO*     3.8    21.3    -      -       +      -
   8001N  STD      5.3    14.4    -      -       +      -
----------------------------------------------------------
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Residues in contact with HIS1242 (chain N). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
   1076N  GLY      5.9     0.9    -      -       -      -
   1079N  LYS*     5.5     0.9    -      -       +      -
   1080N  GLY*     4.6    14.2    -      -       -      -
   1083N  ASP*     4.0    32.1    -      -       +      +
   1084N  THR*     5.2     5.6    -      -       +      +
   1238N  MET*     3.2    29.7    +      -       +      +
   1239N  ARG*     3.0    16.5    +      -       +      +
   1241N  PHE*     1.3    87.8    -      +       -      +
   1243N  THR*     1.3    62.7    +      -       +      +
----------------------------------------------------------
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Residues in contact with THR1243 (chain N). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
   1239N  ARG*     3.1    33.5    +      -       +      +
   1240N  THR      3.6     2.6    +      -       -      -
   1241N  PHE      3.3     3.7    -      -       -      -
   1242N  HIS*     1.3    86.3    -      -       +      +
   1251N  ASP*     3.2    30.9    +      -       -      +
   1253N  THR*     2.7    34.6    +      -       -      +
   1254N  GLN*     5.1     2.7    -      -       -      -
----------------------------------------------------------
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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
------------------------------------------------------------
  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