Contacts of the helix formed by residues 1220 - 1243 (chain D) 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 D).
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
   1041C  GLU      3.3    28.0    -      -       -      +
   1042C  ALA*     3.4    14.3    +      -       -      +
   1043C  TYR      5.5     0.2    +      -       -      -
   1106D  VAL*     4.2    15.0    -      -       +      +
   1218D  GLY      3.7     3.6    +      -       -      -
   1219D  GLU*     1.3    68.7    -      -       -      +
   1221D  VAL*     1.3    60.2    +      -       -      +
   1222D  GLY      3.2     2.9    +      -       -      -
   1223D  ILE*     4.2     5.8    -      -       +      -
   1224D  VAL*     2.9    31.6    +      -       -      +
   1462D  LEU*     4.2    16.2    -      -       +      -
   1474D  ALA*     5.1     4.0    -      -       +      +
   1475D  GLY      5.7     0.2    -      -       -      +
----------------------------------------------------------
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Residues in contact with VAL1221 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
   1105D  ILE*     4.0     9.8    +      -       +      +
   1106D  VAL*     4.6     0.4    -      -       -      +
   1107D  VAL*     3.3    26.2    -      -       +      +
   1200D  VAL*     5.9     2.2    -      -       +      -
   1205D  TYR*     3.3    46.2    -      -       +      +
   1215D  VAL*     4.5     4.0    -      -       +      -
   1219D  GLU*     2.5    29.5    +      -       +      +
   1220D  ALA*     1.3    71.7    -      -       -      +
   1222D  GLY*     1.3    56.9    -      -       -      +
   1224D  VAL*     3.8     8.1    -      -       +      -
   1225D  ALA*     2.7    33.4    +      -       +      +
   1370D  ILE*     4.1    17.3    -      -       +      -
----------------------------------------------------------
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Residues in contact with GLY1222 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
   1102D  THR*     3.2    42.5    -      -       -      +
   1105D  ILE*     3.1    19.0    +      -       -      +
   1220D  ALA      3.2     0.2    -      -       -      -
   1221D  VAL*     1.3    78.7    -      -       -      +
   1223D  ILE*     1.3    56.9    +      -       -      +
   1225D  ALA*     3.3     2.6    -      -       -      +
   1226D  ALA*     2.9    28.0    +      -       -      +
   1370D  ILE*     4.3     1.3    -      -       -      -
----------------------------------------------------------
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Residues in contact with ILE1223 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
   1038C  TRP*     3.8    18.2    -      -       +      +
   1041C  GLU*     4.1    15.5    -      -       +      +
   1042C  ALA*     4.3     7.9    -      -       +      -
   1099D  VAL*     4.6    13.7    -      -       +      -
   1103D  HIS*     3.5    28.9    -      -       +      +
   1105D  ILE      5.1     0.2    -      -       -      +
   1220D  ALA*     3.5    10.0    +      -       +      +
   1221D  VAL      3.3     0.2    -      -       -      -
   1222D  GLY*     1.3    71.1    -      -       -      +
   1224D  VAL*     1.3    60.0    +      -       -      +
   1225D  ALA      2.9     1.8    -      -       -      -
   1226D  ALA*     2.7    27.9    +      -       -      -
   1227D  GLN*     2.7    45.4    +      -       +      +
   1462D  LEU*     3.3    33.2    -      -       +      -
----------------------------------------------------------
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Residues in contact with VAL1224 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
   1042C  ALA*     4.1    20.2    -      -       +      +
    710D  ARG*     4.2    21.5    -      -       -      +
    772D  PRO*     3.6    26.2    -      -       +      +
   1205D  TYR*     4.4    10.1    -      -       +      +
   1208D  ASP*     5.4     2.7    -      -       -      +
   1219D  GLU*     4.4    13.0    -      -       +      +
   1220D  ALA      2.9    29.2    +      -       -      +
   1221D  VAL*     3.5    10.3    -      -       +      +
   1223D  ILE*     1.3    74.6    -      -       -      +
   1225D  ALA*     1.3    52.5    +      -       -      +
   1227D  GLN*     3.7     6.8    +      -       -      +
   1228D  SER*     2.6    31.2    +      -       -      -
   1367D  HIS*     3.9    12.3    -      -       +      -
----------------------------------------------------------
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Residues in contact with ALA1225 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
   1102D  THR*     5.0     0.7    -      -       +      -
   1221D  VAL*     2.7    21.5    +      -       +      +
   1222D  GLY      3.3     4.5    -      -       -      +
   1223D  ILE      2.7     0.2    +      -       -      -
   1224D  VAL*     1.3    71.2    -      -       -      +
   1226D  ALA*     1.3    66.8    +      -       -      +
   1227D  GLN      3.0     1.3    -      -       -      -
   1228D  SER*     2.5    19.1    +      -       -      -
   1229D  ILE*     3.3    13.1    +      -       +      +
   1367D  HIS*     2.8    30.3    +      -       -      +
   1370D  ILE*     3.7    28.7    -      -       +      -
   1371D  VAL*     5.1     0.9    -      -       +      -
----------------------------------------------------------
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Residues in contact with ALA1226 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
   1095D  THR*     4.1     5.7    -      -       -      +
   1098D  LEU*     3.4    40.3    -      -       +      +
   1099D  VAL*     3.7    29.4    -      -       +      -
   1102D  THR*     5.0     1.3    -      -       -      -
   1222D  GLY      2.9    13.5    +      -       -      +
   1223D  ILE*     2.7    13.1    +      -       -      +
   1225D  ALA*     1.3    72.7    -      -       -      +
   1227D  GLN*     1.3    60.1    +      -       -      +
   1229D  ILE*     4.6     2.5    -      -       -      -
   1230D  GLY*     3.3    15.9    +      -       -      -
   1371D  VAL*     5.1     2.8    -      -       -      +
----------------------------------------------------------
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Residues in contact with GLN1227 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
   1035C  MET      4.4     3.2    +      -       -      -
   1038C  TRP*     3.3    44.5    -      -       -      +
   1039C  ALA*     3.9     3.9    -      -       -      +
   1042C  ALA*     5.0     0.9    -      -       -      -
    708D  LEU      4.0    18.3    +      -       -      +
    709D  HIS*     3.0    11.3    -      -       +      -
    710D  ARG*     2.6    41.5    +      -       +      +
    772D  PRO*     6.2     1.6    -      -       +      -
   1095D  THR*     5.0     7.6    -      -       +      +
   1099D  VAL*     5.6     0.2    -      -       +      -
   1223D  ILE*     2.7    36.1    +      -       +      +
   1224D  VAL*     4.0     7.0    -      -       -      +
   1225D  ALA      2.8     1.2    +      -       -      -
   1226D  ALA*     1.3    70.2    -      -       +      +
   1228D  SER*     1.3    53.3    +      -       -      +
   1229D  ILE      2.7    15.6    +      -       -      -
   1230D  GLY      2.8    12.4    +      -       -      +
   1231D  GLU*     3.2    16.1    +      -       -      +
----------------------------------------------------------
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Residues in contact with SER1228 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    709D  HIS*     6.0     1.3    -      -       -      -
    772D  PRO*     5.1     1.1    -      -       -      +
    773D  ALA*     3.1    42.9    -      -       -      +
   1224D  VAL      2.6    14.8    +      -       -      -
   1225D  ALA      2.5    20.4    +      -       -      -
   1227D  GLN*     1.3    73.9    -      -       -      +
   1229D  ILE*     1.3    54.6    +      -       -      +
   1231D  GLU*     4.5     4.3    -      -       -      -
   1232D  PRO*     3.1    25.0    -      -       -      +
   1363D  LEU*     3.6     9.0    -      -       -      +
   1367D  HIS*     3.0    20.6    +      -       -      -
----------------------------------------------------------
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Residues in contact with ILE1229 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
   1094D  LEU*     5.7     4.0    -      -       +      +
   1098D  LEU*     3.3    27.1    -      -       +      -
   1225D  ALA      3.3    13.0    +      -       -      +
   1226D  ALA      3.7     0.7    -      -       -      +
   1227D  GLN      2.7     1.8    +      -       -      -
   1228D  SER*     1.3    80.1    -      -       -      +
   1230D  GLY*     1.3    59.4    +      -       -      +
   1231D  GLU      3.5     0.7    -      -       -      -
   1232D  PRO*     4.0     1.3    -      -       -      -
   1233D  GLY*     3.9     4.2    +      -       -      -
   1259D  VAL*     5.7     0.9    -      -       +      -
   1263D  PHE*     4.2    18.4    -      -       +      -
   1352D  ILE*     6.0     1.3    -      -       +      -
   1356D  TYR*     2.8    42.3    +      -       +      +
   1363D  LEU*     4.1    13.5    -      -       +      -
   1367D  HIS*     3.6    37.5    -      -       +      +
   1368D  ILE*     3.9     9.6    -      -       +      +
   1371D  VAL*     3.7    19.3    -      -       +      -
----------------------------------------------------------
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Residues in contact with GLY1230 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    708D  LEU*     4.6     6.9    -      -       -      +
   1091D  SER*     3.1    24.3    +      -       -      -
   1094D  LEU*     6.4     2.9    -      -       -      -
   1095D  THR*     3.1    27.4    +      -       -      -
   1098D  LEU*     5.0     1.8    -      -       -      -
   1226D  ALA      3.3     5.5    +      -       -      -
   1227D  GLN      2.8     6.0    +      -       -      -
   1229D  ILE*     1.3    80.1    -      -       -      +
   1231D  GLU*     1.3    60.6    +      -       -      +
   1233D  GLY*     3.9     1.7    +      -       -      -
   1234D  THR*     3.1     9.4    +      -       -      -
----------------------------------------------------------
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Residues in contact with GLU1231 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    708D  LEU*     4.3    27.7    +      -       +      +
    709D  HIS*     3.8    34.3    +      -       +      +
    771D  SER*     4.9     2.3    +      -       -      -
    773D  ALA*     4.4    14.1    -      -       -      +
   1227D  GLN      3.2     9.8    +      -       -      +
   1228D  SER*     4.4     3.5    -      -       -      +
   1230D  GLY*     1.3    73.6    -      -       -      +
   1232D  PRO*     1.4    92.4    -      -       +      +
   1233D  GLY      3.0     3.2    +      -       -      -
   1234D  THR*     3.0    23.1    +      -       -      -
   1235D  GLN*     3.6    13.0    +      -       -      +
   1361D  VAL*     5.5     0.9    -      -       -      +
----------------------------------------------------------
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Residues in contact with PRO1232 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    773D  ALA*     5.2     3.6    -      -       +      -
   1228D  SER      3.1    27.1    -      -       -      +
   1229D  ILE      4.0     2.5    -      -       -      -
   1231D  GLU*     1.4   110.4    -      -       +      +
   1233D  GLY*     1.3    51.6    +      -       -      +
   1235D  GLN*     3.1     8.1    +      -       +      +
   1236D  LEU*     2.7    39.8    +      -       -      +
   1356D  TYR*     3.7    11.0    -      -       +      -
   1361D  VAL*     3.2    43.5    -      -       +      -
   1363D  LEU*     5.1     1.1    -      -       +      -
----------------------------------------------------------
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Residues in contact with GLY1233 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
   1091D  SER*     4.4     3.6    -      -       -      -
   1229D  ILE      3.9     7.1    +      -       -      -
   1230D  GLY      4.2     3.4    -      -       -      -
   1231D  GLU      3.0     1.6    +      -       -      -
   1232D  PRO*     1.3    79.7    -      -       -      +
   1234D  THR*     1.3    58.1    +      -       -      +
   1235D  GLN      2.8     0.5    +      -       -      -
   1236D  LEU*     4.5     3.6    -      -       -      -
   1237D  THR*     2.4    53.4    +      -       -      -
   1256D  LEU*     5.7     1.6    -      -       -      -
   1356D  TYR*     4.1    14.9    -      -       -      -
----------------------------------------------------------
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Residues in contact with THR1234 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    708D  LEU*     4.0    26.6    -      -       +      +
   1087D  ARG*     5.4     1.0    -      -       -      +
   1088D  THR*     3.9    29.4    -      -       -      +
   1091D  SER*     3.1    17.6    +      -       -      +
   1230D  GLY      3.1    16.6    +      -       -      -
   1231D  GLU      3.0     7.9    +      -       -      -
   1233D  GLY*     1.3    73.5    -      -       -      +
   1235D  GLN*     1.3    58.5    +      -       -      +
   1237D  THR*     4.4     3.7    -      -       -      +
   1238D  MET*     3.7    26.6    +      -       -      +
   5999D  APC      6.2     2.2    -      -       +      +
----------------------------------------------------------
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Residues in contact with GLN1235 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
   1231D  GLU*     3.6    13.5    +      -       -      +
   1232D  PRO*     3.1     9.5    +      -       -      +
   1233D  GLY      2.8     1.6    +      -       -      -
   1234D  THR*     1.3    81.8    -      -       -      +
   1236D  LEU*     1.3    61.8    +      -       +      +
   1237D  THR      3.5     0.4    -      -       -      -
   1238D  MET*     4.2    12.6    +      -       -      +
   1239D  ARG*     4.7     2.1    +      -       -      +
   1359D  GLN*     3.4    17.3    +      -       -      +
   1361D  VAL*     4.6    17.0    -      -       +      +
----------------------------------------------------------
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Residues in contact with LEU1236 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
   1232D  PRO      2.7    23.3    +      -       -      +
   1233D  GLY*     4.6     2.0    -      -       -      -
   1235D  GLN*     1.3    72.1    -      -       +      +
   1237D  THR*     1.3    65.6    +      -       -      +
   1238D  MET      3.0     5.8    +      -       -      -
   1239D  ARG      3.3     1.4    +      -       -      -
   1240D  THR*     2.4    34.2    +      -       -      +
   1259D  VAL*     5.9     0.2    -      -       +      -
   1355D  VAL*     3.7    31.0    -      -       +      +
   1356D  TYR*     3.3    42.2    -      -       +      +
   1359D  GLN*     3.2    29.8    -      -       +      +
   1361D  VAL*     3.3    39.0    -      -       +      +
----------------------------------------------------------
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Residues in contact with THR1237 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
   1087D  ARG*     3.1    33.9    -      -       +      +
   1091D  SER*     4.7     0.9    -      -       -      -
   1233D  GLY*     2.4    47.7    +      -       -      +
   1234D  THR*     4.4     3.1    -      -       -      +
   1236D  LEU*     1.3    74.7    -      -       -      +
   1238D  MET*     1.3    59.9    +      -       -      +
   1240D  THR*     4.3     2.5    -      -       -      -
   1241D  PHE*     3.4    17.0    +      -       -      +
   1256D  LEU*     2.8    63.4    +      -       +      +
   1259D  VAL*     4.5     3.8    -      -       -      +
----------------------------------------------------------
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Residues in contact with MET1238 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
   1084D  THR*     3.4    61.2    -      -       +      +
   1087D  ARG*     3.6    12.6    -      -       +      -
   1088D  THR*     5.6     1.3    -      -       -      -
   1233D  GLY      4.0     1.2    +      -       -      -
   1234D  THR*     3.7    21.7    +      -       -      +
   1235D  GLN*     4.2     8.3    +      -       -      +
   1236D  LEU*     3.0     1.0    -      -       -      +
   1237D  THR*     1.3    82.5    -      -       -      +
   1239D  ARG*     1.3    57.7    +      -       -      +
   1242D  HIS*     2.5    37.9    +      -       +      +
   5999D  APC      5.3    12.1    -      -       +      +
----------------------------------------------------------
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Residues in contact with ARG1239 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
   1033D  GLN*     5.6    10.3    -      -       -      +
   1235D  GLN      4.7     1.8    +      -       -      -
   1236D  LEU*     3.3     2.6    +      -       -      +
   1238D  MET*     1.3    76.3    -      -       -      +
   1240D  THR*     1.3    61.2    +      -       -      +
   1241D  PHE      3.1     1.6    -      -       -      -
   1242D  HIS*     2.7    39.1    +      -       +      +
   1243D  THR*     3.0    21.9    +      -       +      +
   1359D  GLN*     3.9    36.3    -      -       +      +
----------------------------------------------------------
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Residues in contact with THR1240 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
   1236D  LEU*     2.4    27.6    +      -       -      +
   1237D  THR*     4.6     0.4    -      -       -      -
   1239D  ARG*     1.3    77.2    -      -       -      +
   1241D  PHE*     1.3    61.2    +      -       -      +
   1242D  HIS      3.4     0.2    +      -       -      -
   1243D  THR*     3.5     3.3    +      -       -      -
   1253D  THR*     2.5    51.8    -      -       +      +
   1254D  GLN*     3.1    34.1    -      -       -      +
   1255D  GLY*     2.9    20.8    +      -       -      -
   1355D  VAL*     3.4    10.8    -      -       +      -
   1359D  GLN*     3.4    18.1    -      -       -      +
----------------------------------------------------------
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Residues in contact with PHE1241 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
   1079D  LYS*     6.2     1.6    -      -       -      -
   1083D  ASP*     2.8    37.9    -      -       -      -
   1087D  ARG*     3.5    31.9    -      -       -      +
   1237D  THR      3.4    20.8    +      -       -      +
   1238D  MET      4.3     0.4    -      -       -      +
   1239D  ARG      3.1     0.8    -      -       -      -
   1240D  THR*     1.3    78.8    -      -       -      +
   1242D  HIS*     1.3    75.8    +      -       -      +
   1243D  THR*     3.5     3.3    +      -       -      -
   1254D  GLN*     5.1     0.2    -      -       -      +
   1255D  GLY      3.6     7.1    -      -       -      +
   1257D  PRO*     3.3    36.8    -      -       +      -
   7001D  STD      4.8    23.6    -      -       +      -
----------------------------------------------------------
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Residues in contact with HIS1242 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
   1046D  GLN*     5.8     1.7    +      -       -      -
   1080D  GLY*     4.0    16.7    -      -       -      -
   1083D  ASP*     3.1    40.1    +      -       +      +
   1084D  THR*     4.2    13.9    -      -       -      +
   1087D  ARG*     4.6     0.2    -      -       -      -
   1238D  MET*     2.5    29.6    +      -       +      +
   1239D  ARG*     2.7    28.3    +      -       +      +
   1241D  PHE*     1.3    91.4    -      +       -      +
   1243D  THR*     1.3    63.5    +      -       +      +
----------------------------------------------------------
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Residues in contact with THR1243 (chain D). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
   1239D  ARG*     3.0    18.7    +      -       +      +
   1240D  THR*     3.5     3.2    +      -       -      -
   1241D  PHE      3.3     3.9    -      -       -      -
   1242D  HIS*     1.3    88.2    -      -       +      +
   1251D  ASP*     4.1    25.7    -      -       -      +
   1253D  THR*     3.2    32.2    +      -       -      -
   1254D  GLN*     4.9     5.6    -      -       -      +
----------------------------------------------------------
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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