Beta-sandwiches
The C-terminal domain of peptide:glycosidase F.
This domain consists of 137 amino-acid residues. The simplest all
beta fold is the beta
sandwich in which two essentially independent sheets pack face-to-face
to form a sandwich structure. The two beta sheets
are usually twisted. Packing the sheets at an angle with respect to one
another allows efficient interdigitation of the interior side chains.