Contacts of the helix formed by residues 16 - 25 (chain A) in PDB entry 2ITB
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 PRO 16 (chain A).
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Specific contacts
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Residue Dist Surf HB Arom Phob DC
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14A PRO* 3.4 4.2 - - + +
15A THR* 1.3 96.2 - - + +
17A ASP* 1.3 66.9 + - - +
18A ALA* 4.1 5.4 - - + +
19A TRP* 3.1 14.3 + - + +
20A ILE* 3.4 3.0 + - - +
128A ARG* 3.8 8.5 - - - +
186A ILE* 3.7 28.0 - - + +
187A GLN* 4.6 10.1 - - + +
199A ILE* 3.7 37.9 - - + -
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Residues in contact with ASP 17 (chain A).
Click here for Legend to table.
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Specific contacts
---------------------------
Residue Dist Surf HB Arom Phob DC
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15A THR 3.6 3.1 + - - +
16A PRO* 1.3 71.8 - - - +
18A ALA* 1.3 63.0 + - - +
20A ILE* 3.1 23.1 + - - +
21A GLU* 3.0 23.0 + - - +
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Residues in contact with ALA 18 (chain A).
Click here for Legend to table.
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Specific contacts
---------------------------
Residue Dist Surf HB Arom Phob DC
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16A PRO* 3.2 1.2 - - + +
17A ASP* 1.3 78.5 - - - +
19A TRP* 1.3 60.2 - - - +
21A GLU* 3.8 8.0 + - - +
22A ALA* 3.4 19.9 + - - +
199A ILE* 3.6 34.4 - - + +
200A PRO* 4.5 2.8 - - - +
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Residues in contact with TRP 19 (chain A).
Click here for Legend to table.
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Specific contacts
---------------------------
Residue Dist Surf HB Arom Phob DC
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15A THR* 3.6 14.1 - - + -
16A PRO* 3.1 29.1 + - + +
18A ALA* 1.3 77.0 - - - +
20A ILE* 1.3 73.4 + - + +
22A ALA* 3.1 7.5 + - - +
23A ALA* 3.0 42.1 + - + -
30A LEU* 4.0 14.6 - - + -
128A ARG* 3.4 38.6 - - + +
131A ALA* 6.2 0.2 - - + -
132A LEU* 4.0 22.7 - - + -
193A LEU* 3.8 8.8 - - + +
194A ARG 3.3 10.4 + - - -
195A PHE* 3.3 17.9 - + - -
197A SER* 3.0 26.7 + - - -
198A GLY 3.4 24.5 - - - +
199A ILE* 4.7 4.4 - - + +
200A PRO* 4.5 5.4 - - + -
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Residues in contact with ILE 20 (chain A).
Click here for Legend to table.
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Specific contacts
---------------------------
Residue Dist Surf HB Arom Phob DC
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15A THR* 3.8 23.6 - - + +
16A PRO 3.4 10.5 + - - +
17A ASP* 3.1 23.9 + - - +
19A TRP* 1.3 88.8 - - + +
21A GLU* 1.3 63.7 + - - +
23A ALA* 2.9 3.4 + - - +
24A LEU* 2.9 46.0 + - + +
131A ALA* 4.1 25.1 - - + +
132A LEU* 4.6 8.7 - - + -
135A HIS* 3.8 24.5 - - + +
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Residues in contact with GLU 21 (chain A).
Click here for Legend to table.
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Specific contacts
---------------------------
Residue Dist Surf HB Arom Phob DC
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17A ASP 3.0 15.8 + - - +
18A ALA* 4.0 8.3 - - - +
19A TRP 3.3 0.2 - - - -
20A ILE* 1.3 78.9 - - - +
22A ALA* 1.3 62.5 + - - +
24A LEU* 3.5 8.2 + - - +
25A ALA* 3.3 21.8 + - - +
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Residues in contact with ALA 22 (chain A).
Click here for Legend to table.
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Specific contacts
---------------------------
Residue Dist Surf HB Arom Phob DC
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18A ALA 3.4 10.0 + - - +
19A TRP 3.1 10.4 + - - +
21A GLU* 1.3 79.2 - - - +
23A ALA* 1.3 62.2 + - - +
25A ALA* 3.4 13.3 + - - +
26A ASP* 3.4 10.4 + - - +
193A LEU* 3.9 15.3 - - + +
200A PRO* 3.7 32.1 - - + -
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Residues in contact with ALA 23 (chain A).
Click here for Legend to table.
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Specific contacts
---------------------------
Residue Dist Surf HB Arom Phob DC
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19A TRP* 3.0 44.5 + - + +
20A ILE* 2.9 8.4 + - - +
22A ALA* 1.3 75.6 - - - +
24A LEU* 1.3 65.5 + - - +
26A ASP 3.2 20.1 + - - +
27A GLN* 3.3 8.9 + - - +
30A LEU* 4.2 16.9 - - + +
132A LEU* 4.4 5.4 - - + -
193A LEU* 3.9 13.2 - - + +
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Residues in contact with LEU 24 (chain A).
Click here for Legend to table.
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Specific contacts
---------------------------
Residue Dist Surf HB Arom Phob DC
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20A ILE* 2.9 37.3 + - + +
21A GLU* 4.0 7.9 - - - +
23A ALA* 1.3 77.2 - - - +
25A ALA* 1.3 58.0 + - - +
26A ASP 3.2 0.2 - - - -
27A GLN* 3.1 35.0 + - + +
30A LEU* 6.5 0.2 - - + -
132A LEU* 4.4 7.6 - - + -
135A HIS* 3.8 33.2 - - + +
136A LEU* 3.7 29.4 - - + -
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Residues in contact with ALA 25 (chain A).
Click here for Legend to table.
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Specific contacts
---------------------------
Residue Dist Surf HB Arom Phob DC
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21A GLU 3.3 14.3 + - - +
22A ALA* 3.4 6.0 + - - +
23A ALA 3.2 0.6 - - - -
24A LEU* 1.3 77.2 - - - +
26A ASP* 1.3 60.9 + - - +
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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