Contacts of the helix formed by residues 242 - 265 (chain B) in PDB entry 1ASZ


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 VAL 242 (chain B).
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    116B  HIS*     5.5     2.9    -      -       +      -
    131B  ARG*     4.3     6.7    -      -       -      -
    133B  GLN      4.0    20.4    -      -       -      +
    134B  ALA*     4.0    16.3    -      -       +      +
    136B  LEU*     4.3    26.7    -      -       +      -
    183B  THR*     5.6     4.0    -      -       +      -
    208B  LEU*     5.1     1.4    -      -       -      +
    212B  SER*     4.4     8.0    +      -       -      +
    240B  ARG      3.6     1.1    +      -       -      -
    241B  THR*     1.3    74.7    -      -       -      +
    243B  THR*     1.3    65.6    +      -       +      +
    245B  GLN*     3.4     5.1    -      -       -      +
    246B  ALA*     3.4    16.6    +      -       -      +
    379B  LEU*     3.1    32.5    -      -       +      -
----------------------------------------------------------
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Residues in contact with THR 243 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    212B  SER*     6.0     0.4    -      -       -      -
    241B  THR*     3.3    11.8    +      -       -      -
    242B  VAL*     1.3    78.7    -      -       +      +
    244B  ASN*     1.3    66.1    +      -       -      +
    246B  ALA*     3.1     6.3    +      -       -      +
    247B  ILE*     2.8    26.0    +      -       -      +
    379B  LEU*     3.3    30.3    -      -       +      +
    380B  VAL*     4.0     9.3    -      -       -      +
    383B  GLN*     2.6    49.4    +      -       +      +
    384B  TYR*     4.6    10.5    +      -       -      -
----------------------------------------------------------
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Residues in contact with ASN 244 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    231B  ARG*     5.5     0.8    -      -       -      +
    235B  ARG*     4.8     5.3    +      -       -      -
    238B  ASP*     2.4    52.7    +      -       -      +
    239B  LEU*     3.2    33.2    -      -       +      +
    241B  THR*     3.1    10.9    +      -       -      +
    243B  THR*     1.3    74.4    +      -       -      +
    245B  GLN*     1.3    66.6    +      -       -      +
    247B  ILE*     2.8    31.5    +      -       -      +
    248B  PHE*     2.9    21.0    +      -       +      +
    384B  TYR*     5.2     4.7    +      -       -      -
    544B  ARG*     6.0     0.9    -      -       -      +
----------------------------------------------------------
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Residues in contact with GLN 245 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    312A  ALA      3.5    23.4    +      -       -      -
    313A  ASP*     3.7    20.0    +      -       -      +
    314A  PHE*     4.1    24.8    -      -       -      +
    133B  GLN*     4.1    24.0    +      -       -      +
    134B  ALA*     4.3    12.3    -      -       +      +
    239B  LEU      3.6     9.9    +      -       -      -
    240B  ARG*     4.1     4.8    -      -       -      +
    241B  THR      3.4    14.3    +      -       -      +
    242B  VAL      3.4    10.1    -      -       -      +
    244B  ASN*     1.3    80.5    -      -       -      +
    246B  ALA*     1.3    57.3    +      -       -      +
    248B  PHE*     3.6     2.3    +      -       -      +
    249B  ARG*     3.1    51.8    +      -       -      +
----------------------------------------------------------
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Residues in contact with ALA 246 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    134B  ALA*     5.0     3.6    -      -       +      -
    242B  VAL      3.4     8.1    +      -       -      +
    243B  THR      3.1     7.8    +      -       -      +
    245B  GLN*     1.3    76.6    -      -       -      +
    247B  ILE*     1.3    61.7    +      -       -      +
    249B  ARG*     3.8     5.8    -      -       -      +
    250B  ILE*     2.9    29.8    +      -       -      +
    376B  GLU*     3.2    43.4    -      -       +      +
    379B  LEU*     4.1    15.0    -      -       +      -
    380B  VAL*     4.2     3.1    -      -       +      -
----------------------------------------------------------
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Residues in contact with ILE 247 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    243B  THR      2.8    17.0    +      -       -      +
    244B  ASN*     2.8    34.5    +      -       -      +
    246B  ALA*     1.3    69.9    -      -       -      +
    248B  PHE*     1.3    80.6    +      -       +      +
    249B  ARG      3.0     0.2    -      -       -      -
    250B  ILE*     2.6    39.0    +      -       -      +
    251B  GLN*     3.0     5.3    +      -       +      +
    380B  VAL*     3.8    26.5    -      -       +      -
    384B  TYR*     4.5     8.7    -      -       +      -
    533B  VAL*     5.3     3.8    -      -       +      +
    537B  LEU*     4.8    10.8    -      -       +      -
    539B  LEU*     3.6    24.7    -      -       +      -
    544B  ARG*     5.1     4.9    -      -       +      -
    545B  ALA*     4.4    17.0    -      -       +      -
----------------------------------------------------------
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Residues in contact with PHE 248 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    268A  THR*     5.2     4.4    -      -       -      -
    269A  GLU      5.0     3.1    -      -       -      +
    314A  PHE*     3.8    21.1    -      +       +      -
    235B  ARG*     3.5    10.3    -      -       -      -
    239B  LEU*     3.1    36.3    -      -       +      -
    244B  ASN*     2.9    16.4    +      -       +      +
    245B  GLN      3.8     0.9    -      -       -      +
    247B  ILE*     1.3    84.5    -      -       +      +
    249B  ARG*     1.3    64.9    +      -       -      +
    251B  GLN*     3.4    38.1    -      -       +      +
    252B  ALA*     3.6    15.1    +      -       -      +
    544B  ARG      3.8     2.2    -      -       -      -
    545B  ALA*     3.4    16.4    -      -       -      -
    546B  SER      3.3     9.6    -      -       -      -
    547B  LEU*     3.2    43.3    -      -       +      -
----------------------------------------------------------
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Residues in contact with ARG 249 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    268A  THR*     4.4    26.7    -      -       +      +
    314A  PHE*     5.4     4.2    +      -       -      -
    133B  GLN*     3.7    35.9    -      -       -      +
    134B  ALA*     4.6     8.9    -      -       -      +
    245B  GLN*     3.1    44.3    +      -       -      +
    246B  ALA*     3.6    14.7    -      -       -      +
    247B  ILE      3.0     0.4    -      -       -      -
    248B  PHE*     1.3    76.2    -      -       -      +
    250B  ILE*     1.3    59.0    +      -       -      +
    252B  ALA*     3.1    10.7    +      -       -      +
    253B  GLY      3.0    19.8    +      -       -      -
    373B  PHE*     3.6    15.4    -      -       +      -
    376B  GLU*     3.5    31.4    +      -       +      +
----------------------------------------------------------
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Residues in contact with ILE 250 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    246B  ALA      2.9    18.8    -      -       -      +
    247B  ILE*     2.6     9.7    +      -       -      +
    249B  ARG*     1.3    78.5    -      -       -      +
    251B  GLN*     1.3    66.0    +      -       -      +
    253B  GLY*     3.0     9.5    +      -       -      +
    254B  VAL*     3.2    12.1    +      -       +      +
    369B  LEU*     3.5    28.0    -      -       +      -
    373B  PHE*     4.1    17.7    -      -       +      -
    376B  GLU*     4.4     2.5    -      -       +      +
    377B  ILE*     3.6    40.2    -      -       +      +
    380B  VAL*     5.1     0.7    -      -       +      -
    533B  VAL*     4.4    12.6    -      -       +      -
    536B  TYR*     5.8     2.5    -      -       +      -
    537B  LEU*     4.1    25.8    -      -       +      -
----------------------------------------------------------
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Residues in contact with GLN 251 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    269A  GLU      5.7     0.5    -      -       -      +
    270A  VAL*     5.7     0.5    -      -       -      -
    271A  HIS*     3.7    18.9    +      -       -      +
    247B  ILE*     3.0     7.0    +      -       +      +
    248B  PHE*     3.4    32.7    -      -       +      +
    249B  ARG      3.3     0.4    -      -       -      -
    250B  ILE*     1.3    78.8    -      -       -      +
    252B  ALA*     1.3    58.3    +      -       -      +
    254B  VAL*     3.0    21.0    +      -       -      +
    255B  CYS*     3.4     5.1    +      -       -      -
    339B  THR*     5.3     1.6    -      -       -      +
    529B  LEU*     3.5    39.5    -      -       +      +
    530B  GLU*     4.5     6.5    -      -       -      +
    533B  VAL*     3.6    19.9    -      -       +      +
    545B  ALA      2.9    28.5    +      -       -      -
    546B  SER*     4.0     4.9    -      -       -      +
    547B  LEU*     4.8     7.8    +      -       -      +
----------------------------------------------------------
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Residues in contact with ALA 252 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    268A  THR*     4.9     5.6    -      -       +      -
    269A  GLU*     3.8    44.6    -      -       +      +
    271A  HIS*     5.7     0.9    -      -       +      -
    248B  PHE      3.6     6.1    +      -       -      +
    249B  ARG      3.1    10.2    +      -       -      +
    251B  GLN*     1.3    75.7    -      -       -      +
    253B  GLY*     1.3    64.3    +      -       -      +
    254B  VAL      3.0     2.0    -      -       -      -
    255B  CYS*     3.8    10.3    -      -       -      +
    256B  GLU*     3.1    24.0    +      -       -      +
----------------------------------------------------------
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Residues in contact with GLY 253 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    249B  ARG      3.0     9.7    +      -       -      -
    250B  ILE      3.0     6.0    +      -       -      -
    252B  ALA*     1.3    78.4    -      -       -      +
    254B  VAL*     1.3    55.3    +      -       -      +
    256B  GLU*     3.5     6.2    -      -       -      +
    257B  LEU*     2.8    41.7    +      -       -      +
    369B  LEU*     4.9     1.8    -      -       -      -
    373B  PHE*     3.2    33.4    -      -       -      -
----------------------------------------------------------
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Residues in contact with VAL 254 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    250B  ILE*     3.3    14.4    -      -       +      +
    251B  GLN      3.0     9.8    +      -       -      +
    253B  GLY*     1.3    75.0    -      -       -      +
    255B  CYS*     1.3    66.6    +      -       -      +
    256B  GLU      2.9     2.0    +      -       -      -
    257B  LEU*     3.2     5.8    +      -       -      +
    258B  PHE*     3.0    22.5    +      -       -      +
    341B  LEU*     4.6    12.1    -      -       +      -
    365B  ILE*     4.8    15.5    -      -       +      +
    369B  LEU*     4.0    25.6    -      -       +      -
    529B  LEU*     3.9    16.8    -      -       +      -
    532B  VAL*     4.2    23.3    -      -       +      -
    533B  VAL*     4.2    14.8    -      -       +      -
----------------------------------------------------------
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Residues in contact with CYS 255 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    269A  GLU*     3.4    20.0    -      -       -      +
    271A  HIS*     2.9    40.6    -      -       -      -
    251B  GLN      3.4     7.8    +      -       -      -
    252B  ALA*     3.9     5.8    -      -       -      +
    254B  VAL*     1.3    78.8    -      -       -      +
    256B  GLU*     1.3    60.9    +      -       -      +
    258B  PHE*     3.3    18.9    -      -       -      +
    259B  ARG*     3.4    21.7    +      -       -      +
    320B  ILE*     4.2     6.6    -      -       +      +
    341B  LEU*     4.5     9.4    -      -       -      -
    529B  LEU*     3.4    24.0    -      -       -      -
----------------------------------------------------------
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Residues in contact with GLU 256 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    252B  ALA      3.1    16.6    +      -       -      +
    253B  GLY*     3.5     5.6    -      -       -      +
    254B  VAL      2.9     1.2    -      -       -      -
    255B  CYS*     1.3    75.4    -      -       -      +
    257B  LEU*     1.3    61.0    +      -       -      +
    258B  PHE      3.1     2.1    +      -       -      -
    259B  ARG*     3.4    14.3    +      -       -      +
    260B  GLU*     3.0    31.1    +      -       -      +
    372B  ARG*     4.1    23.6    +      -       -      +
    373B  PHE*     4.3    18.5    -      -       -      -
----------------------------------------------------------
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Residues in contact with LEU 257 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    253B  GLY*     2.8    29.2    +      -       -      +
    254B  VAL*     3.2     4.9    +      -       -      +
    256B  GLU*     1.3    74.7    -      -       +      +
    258B  PHE*     1.3    66.2    +      -       -      +
    260B  GLU*     4.0     4.7    -      -       -      -
    261B  TYR*     2.9    27.5    +      -       -      +
    364B  PHE*     3.2    32.9    -      -       +      +
    365B  ILE*     4.4    15.5    -      -       +      +
    368B  GLU*     3.3    32.3    -      -       +      -
    369B  LEU*     4.7    16.6    -      -       +      +
    372B  ARG*     3.4    34.3    -      -       -      +
    373B  PHE*     4.8     3.1    -      -       +      -
----------------------------------------------------------
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Residues in contact with PHE 258 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    254B  VAL      3.0    13.1    +      -       -      +
    255B  CYS      3.3    11.2    -      -       -      +
    257B  LEU*     1.3    81.7    -      -       -      +
    259B  ARG*     1.3    60.3    +      -       +      +
    261B  TYR*     3.3     3.1    +      -       -      +
    262B  LEU*     3.0    50.9    +      -       +      +
    318B  TYR*     4.1     8.3    -      +       -      -
    320B  ILE*     3.5    31.4    -      -       +      -
    341B  LEU*     3.6    48.7    -      -       +      -
    342B  ASP      4.0     9.9    -      -       -      -
    343B  MET*     4.1     7.6    -      -       +      -
    361B  LEU*     3.6    32.1    -      -       +      -
    365B  ILE*     4.7     8.3    -      -       +      +
    527B  ILE*     4.7     7.4    -      -       +      -
----------------------------------------------------------
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Residues in contact with ARG 259 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    259A  ARG*     3.4    47.4    -      -       -      +
    269A  GLU*     2.5    46.2    +      -       -      -
    318A  TYR*     4.5     2.6    +      -       -      -
    320A  ILE*     5.1     0.2    -      -       -      +
    255B  CYS*     3.4    21.7    +      -       -      +
    256B  GLU*     4.1    10.1    -      -       -      +
    258B  PHE*     1.3    71.8    -      -       -      +
    260B  GLU*     1.3    66.2    +      -       -      +
    262B  LEU*     3.2     6.1    +      -       -      +
    263B  ALA*     3.0    26.7    +      -       -      +
    269B  GLU*     5.1     0.6    +      -       -      -
    318B  TYR*     3.2    37.7    -      -       +      +
    320B  ILE*     3.8    24.9    -      -       +      +
----------------------------------------------------------
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Residues in contact with GLU 260 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    256B  GLU*     3.0    25.9    +      -       +      +
    257B  LEU*     3.8     5.8    -      -       -      +
    259B  ARG*     1.3    78.6    -      -       -      +
    261B  TYR*     1.3    63.4    +      -       -      +
    263B  ALA*     3.6     8.0    +      -       -      +
    264B  THR*     3.1    17.4    +      -       -      +
    364B  PHE*     3.8    11.8    -      -       +      -
    372B  ARG*     2.7    45.4    +      -       -      -
----------------------------------------------------------
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Residues in contact with TYR 261 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    257B  LEU      2.9    17.9    +      -       -      +
    258B  PHE      3.8     1.8    -      -       -      +
    260B  GLU*     1.3    77.9    -      -       -      +
    262B  LEU*     1.3    72.9    +      -       +      +
    264B  THR*     3.3    24.3    +      -       +      -
    265B  LYS*     3.2    33.1    +      -       +      +
    357B  THR*     3.6    13.0    +      -       +      -
    360B  GLU*     2.7    51.3    +      -       +      +
    361B  LEU*     3.5    46.0    -      -       +      +
    364B  PHE*     3.6    33.8    -      +       +      -
----------------------------------------------------------
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Residues in contact with LEU 262 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    258B  PHE*     3.0    53.0    +      -       +      +
    259B  ARG*     3.2     5.6    +      -       -      +
    261B  TYR*     1.3    96.9    -      -       +      +
    263B  ALA*     1.3    58.9    +      -       -      +
    265B  LYS*     2.9    15.9    +      -       -      +
    267B  PHE*     3.1    63.2    +      -       +      -
    318B  TYR*     3.8    27.6    -      -       +      -
    343B  MET*     4.4     7.6    -      -       +      -
    357B  THR*     5.3     0.7    -      -       +      -
    361B  LEU*     4.3    10.5    -      -       +      -
----------------------------------------------------------
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Residues in contact with ALA 263 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    256A  GLU*     5.3     9.4    -      -       -      +
    259B  ARG      3.0    15.7    +      -       -      +
    260B  GLU*     4.1     5.8    -      -       -      +
    261B  TYR      3.3     0.2    -      -       -      -
    262B  LEU*     1.3    72.0    -      -       -      +
    264B  THR*     1.3    57.9    +      -       -      +
    265B  LYS      2.9     5.6    -      -       -      -
    266B  LYS*     3.0    27.1    +      -       -      +
    267B  PHE      4.3    10.3    -      -       -      +
    318B  TYR*     5.7     0.8    -      -       +      -
----------------------------------------------------------
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Residues in contact with THR 264 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    260B  GLU*     3.1    15.6    +      -       -      +
    261B  TYR*     3.3    17.4    +      -       +      -
    263B  ALA*     1.3    79.5    -      -       -      +
    265B  LYS*     1.3    72.3    +      -       +      +
    266B  LYS*     3.3    18.8    +      -       -      +
----------------------------------------------------------
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Residues in contact with LYS 265 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    261B  TYR*     3.2    47.3    -      -       +      +
    262B  LEU      2.9     3.2    +      -       -      +
    264B  THR*     1.3    91.0    +      -       -      +
    266B  LYS*     1.3    72.4    +      -       -      +
    267B  PHE*     3.2    28.5    +      -       +      -
    316B  ARG*     2.9    32.0    +      -       -      +
    345B  MET*     5.6     1.6    -      -       +      -
    357B  THR*     5.0    10.5    -      -       +      +
    360B  GLU*     3.7    18.7    +      -       -      -
----------------------------------------------------------
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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