Aritificial fibrous proteins: A review

摘要

Several kinds of natural fibrous proteins have been chosen as model: silk fibroin from Bombyx mori, silks from various species of spiders and collagens. The dragline silk of the spider Nephila clavipes is able to stretch by 30/100 before breaking and has a high tensile strength. It is stronger per unit weight than high tensile steel. Although the partial sequence of the two components of dragline silk is known, its molecular structure is still far from being clearly established. It is however demonstrated that it contains beta-sheet crystals composed of polyalanine residues. Artificial fibrous proteins have been prepared in vivo using either Escherichia coli or the yeast Pichia Pastoris. As these proteins contain repetitive sequences, there is a risk of deletion at the DNA level.