A tool for calculating and analysing the VH-VL orientation in antibodies.

The relative orientation between the variable domains (VH and VL) influences the topology of the antigen binding site. It is important to consider when building high-resolution models of antibodies.

The VH/VL orientation can be represented by six measures:

HLthe torsion angle between H1 and L1
HC1the bend angle between H1 and C
HC2the bend angle between H2 and C
LC1the bend angle between L1 and C
LC2the bend angle between L2 and C
dcthe length of C

ABangle is a tool that calculates these angles from a PDB structure. Click on the link below to download it. Documentation is included in the download. For a full description of the software, or if you use it, please refer to: Dunbar, J. et al. ABangle: Characterising the VH-VL orientation in antibodies. PEDS. (2013).

The equivalent angles can also be calculated between the analagous domains in T-cell receptors, Vα and Vβ. For more information on this, please see the following paper: Dunbar, J. et al. Examining variable domain orientations in antigen receptors gives insight into TCR-like antibody design. PLOS Comp. Bio. (2014)

Download ABangle

SAbPred paper: Dunbar, J. et al (2016). Nucleic Acids Res. 44. W474-W478 [link]