Nephila clavipes dragline

Sponner, A., Schlott, B., Vollrath, F., Unger, E., Grosse, F., and Weisshart, K. (2005a). Characterization of the protein components of Nephila clavipes dragline silk. Biochemistry 44, 4727—1736. 

Zarkoob et al. (1998, 2004) were the first to report on the electrospinning of silkworm silk and Nephila clavipes dragline protein. They used an HFIP solution of protein as the spinning dope. The resulting fibers had a wide distribution in diameter and the continuity during spinning could be significantly improved. 

Hinman, M.B., and Lewis, R.V. "Isolation of a Clone Encoding a 2nd Dragline Silk Fibroin - Nephila-Clavipes Dragline Silk Is a 2-Protein Fiber". J. Biol. Chem. 267(27), 19320-19324 (1992). 

M.B. Hinman, R.V. Lewis, Isolation ofa clone encoding a 2nd dragline silk fibroin— Nephila-clavipes dragline silk is a 2-protein fiber, J. Biol. Chem. 267 (1992) 19320-19324. 

Mello, C.M.K., Senecal, B., Yeung, P., Vouros, P. and Kaplan, D., Initial characterisation of Nephila Clavipes dragline silk, in Silk polymers. Materials science and Biotechnology, Kaplan, D., Wade, W.W., Farmer, B. and Viney, C. (eds), 1994, Washington American Chemical Society, 67-79. 

Michal, C.A. and Jelinski, L.W., Rotational-echo double-resonance in complex biopolymers a study of Nephila clavipes dragline sUk. Journal of Biomolecular NMR, 1998, 12(2) 231 1. 

Solid-state NMR study of structural heterogeneity in peptides containing both polyalanine and repeated GGA sequences as a local structural model of Nephila clavipes dragline silk (Spidroin 1) has been reported. Solvent treatments prior to the NMR measurements were shown to induce a structural change in these model peptides. Conformation-dependent NMR chemical shifts were used to determine the local structure, including the evaluation of the fraction of several conformations. 

Solid-state C NMR has also been applied to reveal the structure of characteristic sequences in Nephila clavipes dragline silk. " ... 

Figure 8 (a) Schematic drawing of the proposed structure of the dry dragline silk of Nephila clavipes, consisting of /i-pleated nanocrystallites, connected via amorphous chains, (b) Simplificated model, investigated by Termonia [75], Reproduced with permission from [75]. 1994 American Chemical Society... 

Second viral coefficient molcm g Nephila clavipes spider dragline 3.0 X 10 (13)... 

SOI 51 Tobacco Dragline silk (MaSpl) Nephila clavipes ELP filtration human primary chondro- cytes, CHO-Kl Scheller et al 2004... 

IF9 94 E.coli Dragline silk (MaSpl) Nephila clavipes none 96% ethanol 3T3 fibroblasts Agapov et al 2009... 

Hinman, M. B. and R. V. Lewis (1992). Isolation of aclone encoding a second dragline silk fibroin. Nephila clavipes draghne silk is a two-protein fiber. Journal of Biological Chemistry 267(27) 19320-19324. 

Silks are generally defined as protein polymers that are spun into fibers by some lepidoptera larvae such as silkworms, spiders, scorpions, mites, and flies [331-333]. Silk proteins are usually produced within specialized glands after biosynthesis in epithelial cells, followed by secretion into the lumen of these glands where the proteins are stored before being spun into fibers. Silks differ widely in composition, structure, and properties, depending on the specific source. The most extensively characterized silks are from the domesticated silkworm, Bombyx mori, and from spiders Nephila clavipes and Araneus diademaius). Many of the more evolutionarily advanced spiders synthesize different types of silks. Each of these different silks has a different amino acid composition and exhibits mechanical properties tailored to their specific functions reproduction as cocoon capsular stmctures, lines for prey capture, lifeline support (dragline), web constmction, and adhesion [334]. 

Chimeric (fusion) proteins that incorporate the R5 peptide have been synthesized to control and precipitate silica nanoparticles. Po Foo and coworkers have utilized a two-component chimeric protein consisting of the R5 polypeptide (from C. fusiformis) and the self-assembling domain based on the consensus repeat in the major ampullate spidroin protein 1 (MaSpl) of Nephila clavipes spider dragline silk [64]. MaSpl forms highly stable P-sheet secondary stmctures that can be spun into intricate fibers which, when fused with the sihca-templating R5-peptide, allow for the formation of film-like and fibrous silica structures (Figure 1.18). 

The potential use of spider silk as a new biomaterial has led to the evaluation of various heterologous expression systems for the production of recombinant spider silk-like proteins [65]. Partial cDNA constructs of dragline silk protein were cloned and expressed in Escherichia coli [66], mammalian cell lines (MAC-T/bovine and BHK (baby hamster kidney)/hamster) [67], insect-cell lines [68, 69], and transgenic silkworm larvae [69]. Designer synthetic genes based on Nephila clavipes spider dragline and fiagdliform protein sequences have also been expressed in E. coli... 

Chimeric recombinant systems have also been developed, in an effort to combine the mechanical properties of silks with the biological features of other macromolecules. In one study, the consensus sequence of the major component of the dragline silk from Nephila clavipes was bioengineered into protein variants that incorporated RGD domains and expressed in E. coli. These recombinant proteins were able to maintain their beta-sheet forming abilities and were processable into films and fibers. Both RGD recombinant and recombinant silk without RGD supported human mesenchymal stem cell (hMSC) attachment and osteogenic differentiation. A separate study reported the fusion of domains from the major amplullate... 

---