4IDL: LOW Melting Temperature Anti-cholera Toxin Llama VHH Domain

Variable heavy domains derived from the heavy-chain-only antibodies found in camelids (V(H)H domains) are known for their thermal stability. Here, the structure of A9, an anti-cholera toxin V(H)H domain (K(d) = 77 +/- 5 nM) that has an unusually low melting temperature of 319.9 +/- 1.6 K, is reported. The CDR3 residues of A9 form a beta-hairpin that is directed away from the former V(H)-V(L) interfacial surface, exposing hydrophobic residues to the solvent. A DALI structural similarity search showed that this CDR3 conformation is uncommon.
PDB ID: 4IDLDownload
MMDB ID: 107640
PDB Deposition Date: 2012/12/12
Updated in MMDB: 2013/02 
Experimental Method:
x-ray diffraction
Resolution: 2.09  Å
Source Organism:
Similar Structures:
Biological Unit for 4IDL: monomeric; determined by author and by software (PISA)
Molecular Components in 4IDL
Label Count Molecule
Protein (1 molecule)
Single Domain Antibody VHH A9
Molecule annotation
* Click molecule labels to explore molecular sequence information.

Citing MMDB