Contacts of the helix formed by residues 72 - 75 (chain R) in PDB entry 1XU1
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 ARG 72 (chain R).
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Specific contacts
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Residue Dist Surf HB Arom Phob DC
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70R SER* 4.0 16.2 + - - +
71R CYS* 1.3 76.8 - - - +
73R LYS* 1.3 59.1 + - - +
74R GLU* 3.2 38.7 + - + +
75R GLN* 3.0 41.5 + - - +
76R GLY 3.5 0.3 + - - -
77R LYS* 2.9 18.8 + - - +
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Residues in contact with LYS 73 (chain R).
Click here for Legend to table.
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Specific contacts
---------------------------
Residue Dist Surf HB Arom Phob DC
----------------------------------------------------------
121A ASP* 5.4 5.3 + - - -
123A ASP* 5.6 3.6 + - - +
71R CYS 4.1 0.8 + - - -
72R ARG* 1.3 72.5 - - - +
74R GLU* 1.3 81.3 + - + +
75R GLN 3.1 0.4 - - - -
76R GLY* 3.2 13.0 + - - -
77R LYS 3.0 16.0 + - - +
78R PHE* 4.9 2.7 - - + -
89R CYS* 5.2 2.4 - - - -
98R LYS 5.8 0.8 + - - -
99R GLN* 3.4 44.3 + - + +
102R TYR* 4.3 13.5 - - + +
103R PHE* 4.3 8.0 + - - +
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Residues in contact with GLU 74 (chain R).
Click here for Legend to table.
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Specific contacts
---------------------------
Residue Dist Surf HB Arom Phob DC
----------------------------------------------------------
72R ARG* 3.1 42.1 + - + -
73R LYS* 1.3 97.1 + - + +
75R GLN* 1.3 64.7 + - + +
76R GLY 3.5 1.5 + - - -
102R TYR* 3.7 32.5 + - + -
103R PHE* 4.8 4.8 - - - -
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Residues in contact with GLN 75 (chain R).
Click here for Legend to table.
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Specific contacts
---------------------------
Residue Dist Surf HB Arom Phob DC
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70R SER* 4.2 10.6 + - - -
72R ARG* 3.0 26.4 + - + +
74R GLU* 1.3 84.1 - - + +
76R GLY* 1.3 60.1 + - - +
77R LYS* 3.5 18.0 + - + +
103R PHE* 4.1 9.1 - - - -
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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