PDBsum entry 2oaw

Structural protein

PDB id: 2oaw

Contents

Protein chains

65 a.a. *

Metals

_CL ×9

Waters ×134

* Residue conservation analysis

PDB id:

2oaw

Name:

Structural protein

Title:

Structure of shh variant of "bergerac" chimera of spectrin sh3

Structure:

Spectrin alpha chain, brain. Chain: a, b, c, d. Fragment: sh3 domain. Synonym: spectrin, non-erythroid alpha chain, fodrin alpha chain. Engineered: yes

Source:

Gallus gallus. Chicken. Organism_taxid: 9031. Expressed in: escherichia coli. Expression_system_taxid: 469008.

Resolution:

1.90Å R-factor: 0.215 R-free: 0.264

Authors:

A.G.Gabdoulkhakov,L.V.Gushchina,A.D.Nikulin,S.V.Nikonov,A.R.Viguera, L.Serrano,V.V.Filimonov

Key ref:

L.V.Gushchina et al. (2009). Structural and thermodynamic studies of Bergerac-SH3 chimeras. Biophys Chem, 139, 106-115. PubMed id: 19042078

Date:

18-Dec-06 Release date: 08-Apr-08

Protein chains

P07751  (SPTN1_CHICK) -  Spectrin alpha chain, non-erythrocytic 1 from Gallus gallus

Seq: 2477 a.a.

Struc: 65 a.a.*

* PDB and UniProt seqs differ at 10 residue positions (black crosses)

Biophys Chem 139:106-115 (2009)

PubMed id: 19042078

Structural and thermodynamic studies of Bergerac-SH3 chimeras.

L.V.Gushchina, A.G.Gabdulkhakov, S.V.Nikonov, P.L.Mateo, V.V.Filimonov.

ABSTRACT

Bergerac-type chimeras of spectrin SH3 were designed by extending a beta-hairpin by eight amino acids so that the extension protruded from the domain body like a "nose" being exposed to the solvent. A calorimetric study of several Bergerac-SH3 variants was carried out over a wide range of pH values and protein concentrations and the three-dimensional structure of one of them, SHH, was determined. X-ray studies confirmed that the nose had a well defined beta-structure whilst the chimera formed a stable tetramer within the crystal unit because of four tightly packed noses. In the pH range of 4-7 the heat-induced unfolding of some chimeras was complex and concentration dependent, whilst at pH values below 3.5, low protein concentrations of all the chimeras studied, including SHH, seemed to obey a monomolecular two-state unfolding model. The best set of data was obtained for the SHA variant, the unfolding heat effects of which were systematically higher than those of the WT protein (about 16.4 kJ/mol at 323 K), which may be close to the upper limit of the enthalpy gain due to 10 residue beta-hairpin folding. At the same time, the chimeras with high nose stability, which, like SHH, have a hydrophobic (IVY) cluster on their surface, showed a lower apparent unfolding heat effect, much closer to that of the WT protein. The possible reasons for this difference are discussed.