title: Properties of synthetic spider silk fibers based on Argiope aurantia MaSp2.
abstract: Spiders have evolved a complex system of silk producing glands. Each of the glands produces silk with strength and elasticity tailored to its biological purpose. Sequence analysis of the major ampullate silk reveals four highly conserved concatenated blocks of amino acids: (GA) n , A n , GPGXX, and GGX. While the GPGXX motif, which has been hypothesized to be responsible for the extensibility of the fiber, displays natural variation in its precise sequence arrangement and content, correlating these differences with particular fiber properties has been difficult. Three genetic constructs based on the Argiope aurantia sequence were engineered to progressively increase the number of GPGXX repeats in a head-to-tail assembly prior to interruption by another motif. Circular dichroism and Fourier transform infrared spectroscopy of synthetic spider silk spin dopes show secondary structures that correspond to an increase in the repeat number of GPGXX regions and an increase in the extensibility of synthetically spun recombinant fibers.
authors.affiliation: Department of Molecular Biology, University of Wyoming, 1000 East University Avenue, Laramie, Wyoming 82070, USA. abrooks@uwyo.edu
authors.forename: Amanda E
authors.initials: AE
authors.lastname: Brooks
authors.forename: Shane M
authors.initials: SM
authors.lastname: Stricker
authors.forename: Sangeeta B
authors.initials: SB
authors.lastname: Joshi
authors.forename: Timothy J
authors.initials: TJ
authors.lastname: Kamerzell
authors.forename: C Russell
authors.initials: CR
authors.lastname: Middaugh
authors.forename: Randolph V
authors.initials: RV
authors.lastname: Lewis
mesh_terms: D020816:Amino Acid Motifs; D000595:Amino Acid Sequence; D000818:Animals; D002942:Circular Dichroism; D005349:Fibroins / Q000096:biosynthesis / Q000737:chemistry; D008969:Molecular Sequence Data; D015202:Protein Engineering; D011994:Recombinant Proteins / Q000096:biosynthesis / Q000737:chemistry; D020539:Sequence Analysis, Protein; D047011:Silk / Q000096:biosynthesis / Q000737:chemistry*; D012995:Solubility; D013112:Spiders / Q000378:metabolism*; D013314:Stress, Mechanical; D013329:Structure-Activity Relationship
chemical_list: D011994:Recombinant Proteins; D047011:Silk; C076815:spidroin 2; D005349:Fibroins