Contacts of the helix formed by residues 252 - 275 (chain B) in PDB entry 3GUC


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 ALA 252 (chain B).
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     71A  ILE*     5.2     7.0    -      -       +      -
     95A  CYS*     4.0    25.0    -      -       +      +
    270A  LEU*     3.8    29.2    -      -       +      +
    274A  LEU*     4.8    11.7    -      -       +      -
    251B  ALA*     1.3    79.1    -      -       -      +
    253B  SER*     1.3    61.7    +      -       -      +
    254B  LEU      3.3     0.2    -      -       -      -
    255B  PRO*     3.1    11.1    -      -       -      +
    256B  THR*     3.0    19.6    +      -       -      -
----------------------------------------------------------
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Residues in contact with SER 253 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    267A  GLN*     2.8    24.3    +      -       -      -
    270A  LEU*     4.0     4.7    -      -       -      +
    276A  PHE*     4.4    21.6    -      -       -      -
    210B  ASN      5.2     1.6    -      -       -      -
    211B  ALA*     3.7    22.5    +      -       -      -
    212B  VAL*     5.4     1.3    -      -       -      +
    251B  ALA      4.1     4.0    -      -       -      +
    252B  ALA*     1.3    81.6    -      -       -      +
    254B  LEU*     1.3    56.8    +      -       -      +
    256B  THR*     3.1     3.3    +      -       -      -
    257B  THR*     2.8    32.1    +      -       -      -
    287B  ALA*     5.1     1.7    -      -       -      +
----------------------------------------------------------
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Residues in contact with LEU 254 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    207B  VAL*     3.9     7.0    -      -       +      -
    208B  SER      3.8    22.0    -      -       -      +
    209B  GLU*     4.4    10.5    -      -       -      +
    211B  ALA*     3.3    18.8    -      -       +      +
    251B  ALA*     4.3    13.1    -      -       -      +
    253B  SER*     1.3    78.8    -      -       -      +
    255B  PRO*     1.4    68.2    -      -       +      +
    257B  THR*     3.5     1.0    +      -       -      -
    258B  MET*     3.0    59.2    +      -       +      +
----------------------------------------------------------
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Residues in contact with PRO 255 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     91A  MET*     4.8     3.8    -      -       -      +
     94A  ARG*     6.4     1.6    -      -       +      -
     95A  CYS*     5.8     4.9    -      -       -      -
     87B  VAL*     5.9     1.0    -      -       -      +
    251B  ALA      3.3    18.6    -      -       -      +
    252B  ALA*     3.1    15.5    -      -       -      +
    254B  LEU*     1.4    99.2    -      -       +      +
    256B  THR*     1.3    55.9    +      -       -      +
    258B  MET*     3.6    13.9    +      -       +      +
    259B  GLY*     3.0    21.8    +      -       -      -
----------------------------------------------------------
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Residues in contact with THR 256 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     91A  MET*     3.9    21.2    -      -       +      +
     95A  CYS*     4.2     5.0    -      -       -      -
    263A  GLY      3.3    27.1    -      -       -      +
    266A  VAL*     3.9     9.8    -      -       +      +
    267A  GLN*     3.7    29.2    -      -       -      +
    270A  LEU*     3.7     8.4    -      -       -      +
    252B  ALA      3.0    15.7    +      -       -      -
    253B  SER*     3.1     8.8    +      -       -      -
    255B  PRO*     1.3    77.1    -      -       -      +
    257B  THR*     1.3    65.2    +      -       -      +
    259B  GLY*     3.0     3.6    +      -       -      -
    260B  VAL*     3.0    22.7    +      -       -      +
----------------------------------------------------------
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Residues in contact with THR 257 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    267A  GLN*     2.9    22.5    +      -       -      +
    207B  VAL*     4.0    20.6    -      -       +      -
    211B  ALA*     2.7    29.9    +      -       -      +
    213B  SER      4.0    14.6    -      -       -      +
    253B  SER      2.8    14.5    +      -       -      -
    254B  LEU      3.9     3.8    -      -       -      -
    256B  THR*     1.3    71.6    -      -       -      +
    258B  MET*     1.3    62.8    +      -       -      +
    260B  VAL*     3.3     1.7    +      -       -      +
    261B  VAL*     3.0    24.4    +      -       +      +
    285B  TYR*     3.8    23.6    -      -       +      -
    287B  ALA*     3.9     0.9    -      -       +      +
----------------------------------------------------------
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Residues in contact with MET 258 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     83B  GLY*     3.6    31.9    -      -       -      +
     84B  VAL*     4.0    19.4    -      -       +      +
     87B  VAL*     5.1     6.1    -      -       +      -
    207B  VAL*     4.1    25.5    -      -       +      +
    254B  LEU*     3.0    51.9    +      -       +      +
    255B  PRO*     3.7    10.1    -      -       +      +
    257B  THR*     1.3    76.1    -      -       -      +
    259B  GLY*     1.3    57.2    +      -       -      +
    261B  VAL*     3.9     1.2    -      -       -      +
    262B  ALA*     2.9    32.7    +      -       -      +
----------------------------------------------------------
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Residues in contact with GLY 259 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     91A  MET*     5.1     8.5    -      -       -      -
    259A  GLY      5.0     8.3    -      -       -      +
    263A  GLY*     5.5     1.6    -      -       -      -
     87B  VAL*     4.7    13.0    -      -       -      +
     91B  MET*     5.2     0.9    -      -       -      +
    255B  PRO      3.0    12.2    +      -       -      -
    256B  THR*     3.0     8.1    +      -       -      -
    258B  MET*     1.3    73.8    -      -       -      +
    260B  VAL*     1.3    58.7    +      -       -      +
    262B  ALA*     3.5     5.0    +      -       -      +
    263B  GLY*     2.9    26.2    +      -       -      -
----------------------------------------------------------
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Residues in contact with VAL 260 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    260A  VAL*     4.6    10.1    -      -       +      +
    263A  GLY*     3.6    32.3    -      -       -      +
    264A  ILE*     3.7    17.9    -      -       +      +
    267A  GLN*     4.9     0.2    -      -       -      +
    256B  THR      3.0    13.5    +      -       -      +
    257B  THR      3.8     1.3    -      -       -      +
    259B  GLY*     1.3    74.6    -      -       -      +
    261B  VAL*     1.3    63.8    +      -       -      +
    263B  GLY*     3.2     2.5    +      -       -      -
    264B  ILE*     3.0    45.0    +      -       +      +
    285B  TYR*     3.7    44.0    -      -       +      +
    292B  PHE*     4.7     0.2    -      -       +      -
----------------------------------------------------------
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Residues in contact with VAL 261 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     84B  VAL*     4.2    13.5    -      -       +      -
    205B  SER*     4.4     2.5    -      -       -      -
    206B  GLY      3.9     9.0    -      -       -      +
    207B  VAL*     3.9    20.0    -      -       +      -
    214B  GLY*     3.9    19.3    -      -       -      -
    215B  HIS*     3.8    24.5    -      -       -      +
    216B  ILE*     3.8     9.9    -      -       +      +
    257B  THR*     3.0    20.3    +      -       +      +
    258B  MET      4.0     1.3    -      -       -      +
    260B  VAL*     1.3    75.5    -      -       -      +
    262B  ALA*     1.3    57.0    +      -       -      +
    264B  ILE*     3.8     6.1    -      -       +      +
    265B  LEU*     2.9    27.9    +      -       -      +
    285B  TYR*     4.2    16.6    -      -       +      -
----------------------------------------------------------
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Residues in contact with ALA 262 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     84B  VAL*     3.9    10.3    -      -       +      +
     87B  VAL*     3.5    34.1    -      -       +      -
     88B  THR*     3.6    20.0    -      -       -      +
     91B  MET*     4.2     2.0    -      -       -      -
    258B  MET      2.9    19.9    +      -       -      +
    259B  GLY      3.8     0.9    -      -       -      +
    261B  VAL*     1.3    78.3    -      -       -      +
    263B  GLY*     1.3    57.4    +      -       -      +
    265B  LEU*     3.3     3.0    +      -       -      +
    266B  VAL*     2.9    34.1    +      -       -      +
----------------------------------------------------------
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Residues in contact with GLY 263 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    256A  THR*     3.6     5.1    +      -       -      -
    259A  GLY      5.6     0.7    -      -       -      -
    260A  VAL*     3.7    18.6    -      -       -      -
     91B  MET*     3.8    24.3    -      -       -      -
    259B  GLY      2.9    15.5    +      -       -      -
    260B  VAL      3.7     2.2    -      -       -      -
    262B  ALA*     1.3    72.9    -      -       -      +
    264B  ILE*     1.3    59.2    +      -       -      +
    266B  VAL*     3.3     0.7    +      -       -      -
    267B  GLN*     2.9    30.1    +      -       -      +
----------------------------------------------------------
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Residues in contact with ILE 264 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    260A  VAL*     3.8    12.5    -      -       +      +
    285A  TYR*     5.0     3.6    -      -       +      +
    290A  ASP*     4.8     1.3    -      -       -      +
    292A  PHE*     3.8    30.7    -      -       +      -
    216B  ILE*     3.6    16.2    -      -       +      -
    260B  VAL*     3.0    39.0    +      -       +      +
    261B  VAL*     3.8     6.3    -      -       -      +
    263B  GLY*     1.3    74.4    -      -       -      +
    265B  LEU*     1.3    63.3    +      -       -      +
    267B  GLN*     3.4     6.1    +      -       -      +
    268B  ASN*     3.1    27.3    +      -       -      +
    283B  LEU*     3.1    36.3    -      -       +      +
    285B  TYR*     5.3     5.2    -      -       +      -
    292B  PHE*     4.3     7.6    -      -       +      -
----------------------------------------------------------
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Residues in contact with LEU 265 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     84B  VAL*     4.7     1.8    -      -       +      -
     88B  THR*     3.6    31.6    -      -       +      +
    179B  LEU*     4.3    12.8    -      -       +      -
    180B  SER      5.5     0.2    -      -       -      +
    181B  CYS*     4.0    19.1    -      -       -      -
    203B  MET*     3.9    36.8    -      -       +      +
    205B  SER*     4.1    14.6    -      -       -      +
    216B  ILE*     3.8    27.3    -      -       +      +
    261B  VAL      2.9    15.1    +      -       -      +
    262B  ALA      3.3     8.9    +      -       -      +
    264B  ILE*     1.3    77.2    -      -       -      +
    266B  VAL*     1.3    58.2    +      -       -      +
    268B  ASN*     3.2     3.3    +      -       -      +
    269B  VAL*     2.8    31.4    +      -       -      +
----------------------------------------------------------
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Residues in contact with VAL 266 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    256A  THR*     4.1    18.8    -      -       +      -
     88B  THR*     3.8    27.4    -      -       +      +
     91B  MET*     3.8    36.8    -      -       +      -
     92B  LEU*     3.7    22.4    -      -       +      -
     95B  CYS*     4.7     3.8    -      -       -      -
    262B  ALA      2.9    23.1    +      -       -      +
    263B  GLY      3.8     3.4    -      -       -      +
    265B  LEU*     1.3    72.5    -      -       -      +
    267B  GLN*     1.3    59.0    +      -       -      +
    269B  VAL*     3.0     9.3    +      -       -      +
    270B  LEU*     2.8    32.2    +      -       +      +
----------------------------------------------------------
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Residues in contact with GLN 267 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    253A  SER*     3.1    29.5    +      -       -      -
    256A  THR*     3.5    18.1    +      -       -      +
    257A  THR*     2.9    29.1    +      -       -      +
    260A  VAL*     4.8     0.2    -      -       -      +
    285A  TYR*     2.8    29.5    +      -       -      +
    287A  ALA*     3.4    22.8    -      -       -      +
    290A  ASP*     5.0     1.6    -      -       -      +
    263B  GLY      2.9    17.0    +      -       -      +
    264B  ILE*     3.6     6.1    -      -       -      +
    266B  VAL*     1.3    77.7    -      -       -      +
    268B  ASN*     1.3    58.1    +      -       -      +
    270B  LEU*     3.3     8.9    +      -       -      +
    271B  LYS*     2.9    35.0    +      -       +      +
    276B  PHE*     4.7     2.7    -      -       -      -
----------------------------------------------------------
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Residues in contact with ASN 268 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    290A  ASP*     2.7    32.3    +      -       -      +
    203B  MET*     3.6    14.8    -      -       +      +
    216B  ILE*     3.7    21.1    -      -       +      +
    264B  ILE*     3.1    26.7    +      -       -      +
    265B  LEU      3.7     3.4    -      -       -      +
    267B  GLN*     1.3    74.9    -      -       -      +
    269B  VAL*     1.3    59.8    +      -       -      +
    271B  LYS*     3.3    10.0    +      -       -      +
    272B  PHE*     2.8    31.2    +      -       -      +
    279B  VAL*     3.5    11.5    -      -       +      +
    280B  SER*     2.8    32.8    +      -       -      +
----------------------------------------------------------
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Residues in contact with VAL 269 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     76B  VAL*     4.4     8.1    -      -       +      -
     92B  LEU*     4.0    20.2    -      -       +      -
    177B  LEU*     3.7    13.2    -      -       +      -
    179B  LEU*     3.6    38.6    -      -       +      -
    203B  MET*     3.9    10.0    -      -       -      +
    265B  LEU*     2.8    23.8    +      -       +      +
    266B  VAL*     3.3    11.0    -      -       -      +
    268B  ASN*     1.3    72.2    -      -       -      +
    270B  LEU*     1.3    58.2    +      -       +      +
    272B  PHE*     3.3     1.6    +      -       -      +
    273B  LEU*     2.8    51.7    +      -       +      +
----------------------------------------------------------
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Residues in contact with LEU 270 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    252A  ALA*     3.5    43.5    -      -       +      +
    253A  SER*     4.1     6.7    -      -       -      +
    256A  THR*     3.6    18.8    -      -       +      -
     71B  ILE*     3.9    31.4    -      -       +      -
     92B  LEU*     4.7     8.7    -      -       +      -
     95B  CYS*     4.3     9.2    -      -       -      -
    266B  VAL*     2.8    22.5    +      -       +      +
    267B  GLN*     3.6    11.0    -      -       -      +
    269B  VAL*     1.3    73.6    -      -       +      +
    271B  LYS*     1.3    58.0    +      -       -      +
    273B  LEU*     4.8     3.4    -      -       +      -
    274B  LEU*     2.9    42.9    +      -       +      +
    276B  PHE*     3.8    12.6    -      -       +      -
----------------------------------------------------------
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Residues in contact with LYS 271 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    287A  ALA      3.0    29.0    +      -       -      +
    288A  MET*     3.3    18.8    +      -       -      +
    290A  ASP*     3.2    25.0    +      -       -      -
    267B  GLN*     2.9    21.8    +      -       +      +
    268B  ASN*     3.7    23.1    -      -       -      +
    270B  LEU*     1.3    75.5    -      -       -      +
    272B  PHE*     1.3    56.4    +      -       -      +
    275B  ASN*     3.0    28.2    +      -       -      -
    276B  PHE*     3.3    47.4    +      -       +      +
    277B  GLY*     4.3     0.7    -      -       -      -
    278B  THR      2.8    24.3    +      -       -      +
    279B  VAL*     4.0    11.2    -      -       +      +
----------------------------------------------------------
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Residues in contact with PHE 272 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    176B  ASP*     3.7    21.8    -      -       +      -
    177B  LEU*     3.7    13.2    -      -       +      -
    201B  THR*     3.7    35.4    -      -       +      -
    203B  MET*     3.9    12.1    -      -       +      -
    218B  LEU*     4.6    13.0    -      -       +      -
    220B  ILE*     5.8     4.3    -      -       +      -
    268B  ASN      2.8    17.6    +      -       -      +
    269B  VAL      3.6     2.9    -      -       -      +
    271B  LYS*     1.3    77.3    -      -       -      +
    273B  LEU*     1.3    79.9    +      -       +      +
    275B  ASN*     3.8     6.1    +      -       -      +
    279B  VAL*     3.6    18.7    -      -       +      +
----------------------------------------------------------
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Residues in contact with LEU 273 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     70B  LYS*     4.9     1.2    -      -       -      +
     71B  ILE*     5.3     3.1    -      -       +      -
     74B  PHE*     3.4    45.5    -      -       +      -
     76B  VAL*     4.1     5.4    -      -       +      -
     92B  LEU*     5.9     0.2    -      -       +      -
     97B  ILE*     3.8    26.9    -      -       +      -
    176B  ASP*     3.8    28.0    -      -       +      -
    177B  LEU*     4.5     6.7    -      -       +      -
    269B  VAL*     2.8    42.7    +      -       +      +
    270B  LEU*     4.3     4.7    -      -       +      +
    272B  PHE*     1.3    94.2    -      -       +      +
    274B  LEU*     1.3    65.4    +      -       +      +
    275B  ASN*     3.8     1.4    +      -       -      +
----------------------------------------------------------
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Residues in contact with LEU 274 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    246A  ARG*     5.3     4.5    -      -       -      +
    248A  GLY      4.3    19.3    -      -       -      +
    249A  VAL*     4.5    10.8    -      -       +      +
    252A  ALA*     4.4    13.9    -      -       +      -
     70B  LYS*     4.0    31.7    +      -       +      -
     71B  ILE*     4.1    21.3    -      -       +      +
     74B  PHE*     4.0    18.8    -      -       +      -
    270B  LEU*     2.9    25.5    +      -       +      +
    273B  LEU*     1.3    82.4    -      -       +      +
    275B  ASN*     1.3    72.8    +      -       -      +
    276B  PHE*     3.6    27.7    -      -       +      +
----------------------------------------------------------
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Residues in contact with ASN 275 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
     70B  LYS*     6.0     1.1    -      -       -      +
    271B  LYS      3.0    12.2    +      -       -      -
    272B  PHE      3.8     5.3    +      -       -      +
    273B  LEU      3.5     3.2    -      -       -      +
    274B  LEU*     1.3    83.6    -      -       -      +
    276B  PHE*     1.3    59.6    +      -       -      +
    277B  GLY      5.3     0.2    -      -       -      -
----------------------------------------------------------
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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