FIBROUS PROTEINS - SILK AS A MODEL SYSTEM

The repetitive nature of fibrous proteins leads to regular secondary a nd higher order structures. This attribute suggests that these polymer s are useful models to gain insight into structure-function relationsh ips. Genetic variants of these proteins can be constructed from precis ely defined synthetic oligonucleotides to encode the specific sized pr otein of interest. The biosynthesis and assembly of this type of prote in is addressed using spider dragline and silkworm cocoon silks. This review includes an overview of: (a) spider dragline silk composition a nd genetics, and (b) the assembly of silk proteins, including the form ation of mesophases and control of crystalline structure. Silks are en vironmentally stable, yet biodegradable under appropriate conditions, leading to a wide range of potential applications for these polymers. (C) 1998 Elsevier Science Limited. All rights reserved.