PDBsum entry 1ieh

Immune system

PDB id: 1ieh

Contents

Protein chain

135 a.a. *

* Residue conservation analysis

PDB id:

1ieh

Name:

Immune system

Title:

Solution structure of a soluble single-domain antibody with hydrophobic residues typical of a vl/vh interface

Structure:

Bruc.D4.4. Chain: a. Fragment: single domain antibody from a naive llama library. Engineered: yes

Source:

Lama glama. Llama. Organism_taxid: 9844. Expressed in: escherichia coli. Expression_system_taxid: 562

NMR struc:

10 models

Authors:

W.Vranken,D.Tolkatchev,P.Xu,J.Tanha,Z.Chen,S.Narang,F.Ni

Key ref:

W.Vranken et al. (2002). Solution structure of a llama single-domain antibody with hydrophobic residues typical of the VH/VL interface. Biochemistry, 41, 8570-8579. PubMed id: 12093273 DOI: 10.1021/bi012169a

Date:

09-Apr-01 Release date: 07-Aug-02

Protein chain

No UniProt id for this chain

Struc: 135 a.a.

DOI no: 10.1021/bi012169a

Biochemistry 41:8570-8579 (2002)

PubMed id: 12093273

Solution structure of a llama single-domain antibody with hydrophobic residues typical of the VH/VL interface.

W.Vranken, D.Tolkatchev, P.Xu, J.Tanha, Z.Chen, S.Narang, F.Ni.

ABSTRACT

The three-dimensional structure of a llama single-domain antibody BrucD4-4 was established by use of solution NMR spectroscopy. BrucD4-4 has Val, Gly, Leu, and Trp residues at positions 37, 44, 45, and 47, which are considered to be a hallmark to distinguish llama VH from V(H)H fragments at the germline level. In contrast to the murine and human VHs, BrucD4-4 has sufficient solubility, is monomeric in solution, and displays high-quality NMR spectra characteristic of well-structured proteins. Amide proton/deuterium exchange and the (15)N relaxation data showed that BrucD4-4 has a classic protein structure with a well-packed core and comparatively mobile surface loops. The three-dimensional architecture of BrucD4-4 is analogous to that of VHs from murine and human F(v)s and camelid V(H)Hs with two pleated beta-sheets formed by four and five beta-strands. A canonical and undistorted beta-barrel exposes a number of hydrophobic residues into the solvent on the surface of the three-dimensional structure. The eight-residue H3 loop folds over the side chain of Val37 similarly to that in llama V(H)Hs; however, this interaction may be transient due to the H3 conformational flexibility. Overall, the surface characteristics of BrucD4-4 with respect to hydrophobicity appear to lie between the human VH domain from Fv Pot and the llama V(H)H fragment HC-V, which may explain its enhanced solubility allowing NMR structural analysis.