This protein has a 5-fold rotational axis of symmetry.

Merritt, E. A., Sarfaty, S., Chang, T. T., Palmer, L. M., Jobling, M. G., Holmes, R. K., Hol, W. G.: Surprising leads for a cholera toxin receptor-binding antagonist: crystallographic studies of CTB mutants. Structure 3 pp. 561 (1995) (PubMed)

1chp (PDB)

planar hexamer