 |
PDBsum entry 6cha
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
 |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Hydrolase (serine proteinase)
|
PDB id
|
|
|
|
6cha
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
 |
Contents |
 |
|
|
|
|
|
|
|
|
|
|
|
|
* Residue conservation analysis
|
|
|
|
|
References listed in PDB file
|
|
|
Key reference
|
|
|
Title
|
|
Structure of a tetrahedral transition state complex of alpha-Chymotrypsin dimer at 1.8-A resolution.
|
|
|
Authors
|
|
A.Tulinsky,
R.A.Blevins.
|
|
|
Ref.
|
|
J Biol Chem, 1987,
262,
7737-7743.
|
|
|
PubMed id
|
|
|
|
|
|
Abstract
|
|
|
A 1.8-A resolution x-ray crystallographic restrained least squares refinement
has been carried out on the phenylethane boronic acid (PEBA) complex of
alpha-chymotrypsin dimer (alpha-CHT), and it has been compared to the 1.67-A
resolution structure of the native enzyme. PEBA has a high binding affinity for
alpha-CHT, and the boronate forms a tetrahedral complex with Ser-195 OG of one
molecule of the dimer; the boronate in the other molecule is severely disordered
and does not form a tetrahedral complex. The former could be a model of the
transition state of catalysis. The complex of PEBA X alpha-CHT displays
significant nonequivalence in conformation of side chains between the
independent molecules comparable to the native enzyme, but, like the latter,
shows a high degree of fidelity in the folding of the main chain. The
orientation of the phenyl ring, CA and CB of PEBA, in the specificity sites of
the two molecules is similar, suggesting that recognition is fairly insensitive
to small departures from local symmetry; the same does not apply to the boronate
functionalities suggesting that greater precision is required for catalysis. The
folding of the molecule remains the same upon PEBA binding, but some of the side
chains respond nonequivalently. The latter is a consequence of the inherent
nonequivalence of the native dimer and the asymmetrical nature of the PEBA
binding.
|
|
|
Secondary reference #1
|
|
|
Title
|
|
Least-Squares refinement of two protein molecules per asymmetric unit with and without non-Crystallographic symmetry restrained
|
|
|
Authors
|
|
A.Tulinsky,
R.A.Blevins.
|
|
|
Ref.
|
|
acta crystallogr ,sect b, 1986,
42,
198.
|
|
|
|
Secondary reference #2
|
|
|
Title
|
|
The refinement and the structure of the dimer of alpha-Chymotrypsin at 1.67-A resolution.
|
|
|
Authors
|
|
R.A.Blevins,
A.Tulinsky.
|
|
|
Ref.
|
|
J Biol Chem, 1985,
260,
4264-4275.
|
|
|
PubMed id
|
|
|
|
|
|
|
|
|
Secondary reference #3
|
|
|
Title
|
|
Comparison of the independent solvent structures of dimeric alpha-Chymotrypsin with themselves and with gamma-Chymotrypsin.
|
|
|
Authors
|
|
R.A.Blevins,
A.Tulinsky.
|
|
|
Ref.
|
|
J Biol Chem, 1985,
260,
8865-8872.
|
|
|
PubMed id
|
|
|
|
|
|
|
|
|
Secondary reference #4
|
|
|
Title
|
|
The structure of alpha-Chymotrypsin. II. Fourier phase refinement and extension of the dimeric modification
|
|
|
Authors
|
|
N.V.Raghavan,
A.Tulinsky.
|
|
|
Ref.
|
|
acta crystallogr ,sect b, 1979,
35,
1776.
|
|
|
|
Secondary reference #5
|
|
|
Title
|
|
The structure of alpha-Chymotrypsin. I. The refinement of the heavy-Atom isomorphous derivatives at 2.8 angstroms resolution
|
|
|
Authors
|
|
A.Tulinsky,
N.V.Mani,
C.N.Morimoto,
R.L.Vandlen.
|
|
|
Ref.
|
|
acta crystallogr ,sect b, 1973,
29,
1309.
|
|
|
|
Secondary reference #6
|
|
|
Title
|
|
Variability in the tertiary structure of alpha-Chymotrypsin at 2.8-A resolution.
|
|
|
Authors
|
|
A.Tulinsky,
R.L.Vandlen,
C.N.Morimoto,
N.V.Mani,
L.H.Wright.
|
|
|
Ref.
|
|
Biochemistry, 1973,
12,
4185-4192.
[DOI no: ]
|
|
|
PubMed id
|
|
|
|
|
|
|
|
|
Secondary reference #7
|
|
|
Title
|
|
Asymmetrical changes in the tertiary structure of alpha-Chymotrypsin with change in ph.
|
|
|
Authors
|
|
A.Mavridis,
A.Tulinsky,
M.N.Liebman.
|
|
|
Ref.
|
|
Biochemistry, 1974,
13,
3661-3666.
[DOI no: ]
|
|
|
PubMed id
|
|
|
|
|
|
|
|
|
|
|
|
|
