This family features the antihypertensive and antiviral proteins BDS-I (Swiss:P11494) and BDS-II (Swiss:P59084) expressed by Anemonia sulcata. BDS-I is organised into a triple-stranded antiparallel beta-sheet, with an additional small antiparallel beta-sheet at the N-terminus [1]. Both peptides are known to specifically block the Kv3.4 potassium channel, and thus bring about a decrease in blood pressure [2]. Moreover, they inhibit the cytopathic effects of mouse hepatitis virus strain MHV-A59 on mouse liver cells, by an unknown mechanism [1].

1: Determination of the three-dimensional solution structure of the antihypertensive and antiviral protein BDS-I from the sea anemone Anemonia sulcata: a study using nuclear magnetic resonance and hybrid distance geometry-dynamical simulated annealing. Driscoll PC, Gronenborn AM, Beress L, Clore GM; Biochemistry 1989;28:2188-2198. PMID:2566326

2: Sea anemone peptides with a specific blocking activity against the fast inactivating potassium channel Kv3.4. Diochot S, Schweitz H, Beress L, Lazdunski M; J Biol Chem 1998;273:6744-6749. PMID:9506974