Fold: Spectrin repeat-like

3 helices; bundle, closed, left-handed twist; up-and-down

Lineage:

1. Root: scop
2. Class: All alpha proteins
3. Fold: Spectrin repeat-like
   3 helices; bundle, closed, left-handed twist; up-and-down

Superfamilies:

1. Spectrin repeat (1)
2. Enzyme IIa from lactose specific PTS, IIa-lac (1)
3. Succinate dehydrogenase/fumarate reductase C-terminal domain (1)
4. Smac/diablo (1)
5. beta-Tubulin binding post-chaperonin cofactor Rbl2p (1)
6. Ribosomal protein S20 (1)