Contacts of the helix formed by residues 273 - 278 (chain B) in PDB entry 4IRQ
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.
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 273 (chain B).
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Specific contacts
---------------------------
Residue Dist Surf HB Arom Phob DC
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271B ILE 3.2 0.4 + - - -
272B ALA* 1.3 76.9 - - + +
274B GLN* 1.3 60.1 + - - +
275B LYS 3.1 0.7 - - - -
276B GLN* 2.9 33.0 + - + +
277B GLU* 3.0 26.2 + - + +
322B PRO* 6.2 1.8 - - + -
323B TRP* 4.8 8.2 - - + -
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Residues in contact with GLN 274 (chain B).
Click here for Legend to table.
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Specific contacts
---------------------------
Residue Dist Surf HB Arom Phob DC
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138B ARG* 2.5 26.9 + - - +
221B PHE* 5.9 0.4 - - - +
222B TRP 2.7 30.1 + - - +
269B LYS 3.1 3.5 - - - +
270B ARG* 3.2 29.7 - - + +
271B ILE 3.1 29.1 + - - +
272B ALA 3.1 0.6 + - - -
273B ALA* 1.3 76.0 - - - +
275B LYS* 1.3 62.6 + - - +
277B GLU* 4.3 5.4 - - - -
278B GLN* 3.1 29.7 + - + +
323B TRP* 3.4 38.0 - - + +
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Residues in contact with LYS 275 (chain B).
Click here for Legend to table.
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Specific contacts
---------------------------
Residue Dist Surf HB Arom Phob DC
----------------------------------------------------------
270B ARG* 3.5 29.5 - - + +
272B ALA 3.2 14.1 + - - +
273B ALA 3.1 0.6 - - - -
274B GLN* 1.3 78.0 - - - +
276B GLN* 1.3 76.2 + - - +
278B GLN* 3.0 18.5 + - - +
279B PHE* 3.4 14.3 - - + -
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Residues in contact with GLN 276 (chain B).
Click here for Legend to table.
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Specific contacts
---------------------------
Residue Dist Surf HB Arom Phob DC
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272B ALA 3.9 2.7 + - - +
273B ALA* 2.9 28.3 + - + +
275B LYS* 1.3 107.5 - - + +
277B GLU* 1.3 67.7 + - + +
278B GLN 3.4 1.1 + - - -
279B PHE* 3.6 17.1 + - - +
280B LYS* 3.8 16.5 - - - +
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Residues in contact with GLU 277 (chain B).
Click here for Legend to table.
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Specific contacts
---------------------------
Residue Dist Surf HB Arom Phob DC
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220B ARG* 3.0 27.1 + - - +
221B PHE* 4.5 4.2 - - - -
273B ALA* 3.0 27.6 + - + +
274B GLN* 3.3 2.7 + - - +
276B GLN* 1.3 75.3 - - + +
278B GLN* 1.3 62.2 + - - +
279B PHE 3.0 5.4 - - - -
280B LYS* 3.0 62.4 + - - +
323B TRP* 3.8 32.8 - - + -
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Residues in contact with GLN 278 (chain B).
Click here for Legend to table.
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Specific contacts
---------------------------
Residue Dist Surf HB Arom Phob DC
----------------------------------------------------------
221B PHE* 3.2 32.9 - - + -
224B TRP* 6.1 0.7 - - - -
225B GLY* 5.3 0.2 - - - -
226B ARG* 3.4 35.9 + - + +
229B ASP* 6.1 0.2 - - - +
230B GLU* 5.3 0.9 - - - +
270B ARG* 2.8 52.3 + - - +
274B GLN* 3.1 16.4 + - + +
275B LYS* 3.0 24.8 + - - +
277B GLU* 1.3 76.2 - - - +
279B PHE* 1.3 83.8 + - + +
280B LYS 3.4 0.9 - - - +
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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
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Atomic class I II III IV V VI VII VIII
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I (Hydrophilic) + + + - + + + +
II (Acceptor) + - + - + + + -
III (Donor) + + - - + + - +
IV (Hydrophobic) - - - + + + + +
V (Aromatic) + + + + + + + +
VI (Neutral) + + + + + + + +
VII (Neutral-donor) + + - + + + - +
VIII (Neutral-acceptor) + - + + + + + -
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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