Double-Jelly roll fold, vertical

The double jelly-roll fold consists of two single jelly roll folds oriented vertically and connected by a short linker region. It is assembled in hexamers of T=25 to T=1200 capsids. Also called PRD1-adenovirus fold.

Origin:

cellular ancestor

Topology

The strands are traditionally labeled B through I for the historical reason that the first solved structure, the jelly-roll capsid protein of the tomato bushy stunt virus, had an additional strand A outside the common core of the fold. The sheets are composed of strands BIDG and CHEF, which are folded so that strand B is opposite strand C, I opposite H, and so on.(source wikipedia).