Twisted single crystals of Bombyx mori silk fibroin and related model polypeptides with β structure

摘要: Abstract Lamellar, chain-folded single crystals and crystal aggregates of a protein (Bombyx mori silk fibroin) various copolypeptides alanine glycine with β structure are observed to be helically twisted. The amount twist depends on the morphology crystallization conditions, possibly residue sequence: sense twist, however, is always same, dictated by chirality optically active residue(s). twisted provide morphological evidence in support favoured reported for sheets globular proteins (Chothia, 1973). similar to, but has different origin from, that certain crystalline morphologies synthetic polymers.