（法新社洛杉磯十四日電） 蜘蛛界令人聞之色變的黑寡婦，製造出來的蜘蛛絲可能搖身一變，成為超強護身盔甲？加州大學河濱分校科學家宣布，已經辨識出黑寡婦基因及DNA序列裡兩種關鍵蛋白質，「黑寡婦牌」盔甲未來可能成真。
圖1. 雌性黑寡婦蜘蛛
加州大學在新聞稿中表示，這項發現未來用途極廣，創造出來的新材料可以應用在產業界、醫學及軍事方面等。
蜘蛛絲其實相當強韌，其中黑寡婦蜘蛛絲的強度及延展性又特別強，能夠承受極大能量的衝擊。蜘蛛絲的強韌特性也引起軍事、運動及醫療界的興趣，想要進一步發展出極輕的身體護甲、特殊運動服裝或應用在醫療設備上。
圖2. 蜘蛛造絲器官顯微圖（圖片來源：http://www.goodsky.homestead.com/files/silk.html）
目前市面上並沒有蜘蛛絲製成的產品，研究團隊領導人哈雅希說：「目前沒有什麼比自然蜘蛛絲更好的材料，進行整體基因分析後，相信我們又往前邁進了一大步。」
她說，根據目前所得的研究結果，蜘蛛絲的基因藍圖未來可能注入生物宿主，例如細菌、植物或動物，利用合成過程製造出蛋白質。
接下來要把蛋白質轉化成絲纖維，質地又必須與真正的蜘蛛絲相同，將是未來的另一挑戰。
英文原文：
Biologists Unravel The Genetic Secrets Of Black Widow Spider Silk
Science Daily — Biologists at the University of California, Riverside have identified the genes, and determined the DNA sequences, for two key proteins in the "dragline silk" of the black widow spider -- an advance that may lead to a variety of new materials for industrial, medical and military uses.
圖1. Female black widow spider (Latrodectus hesperus) walking on web made of dragline silk. (Credit: Mark Chappell, UCR)
The black widow spider's dragline silk is a standout compared to other spider silks because of its superior strength and extensibility, a combination which enables black widow dragline silk to absorb enormous amounts of energy. These properties suggest that synthetically-produced silk might find applications as diverse as lightweight super-strong body armor, components of medical devices and high-tech athletic attire.
The researchers -- Associate Professor of Biology Cheryl Hayashi, postdoctoral researchers Nadia Ayoub and Jessica Garb, and graduate students Robin Tinghitella and Matthew Collin -- report their findings in the June 13 online edition of the journal PLoS ONE. In the article, they describe their work to identify the genes encoding the two key proteins, named MaSp1 and MaSp2, and determine the genes' complete DNA sequences. The UCR Office of Technology Commercialization has filed a patent application on the gene sequences.
圖3. Complete amino acid sequence for L. hesperus major ampullate spidroin 1 (MaSp1). The sequence is read from left to right and then top to bottom. The diamond marks the start position and the asterisk denotes the stop position. The protein is dominated by poly-A (red) and GGX (green) motifs. The majority of the sequence can be categorized into four types of ensemble repeat units. Repeats of each type are aligned within a box. Gaps (-) have been inserted in order to align repeat units within a type.
There are currently no products on the market based on the dragline silk of spiders. "There's nothing quite as good yet as natural dragline silk, but we should get a lot closer now that we have the full genetic recipe," Hayashi said.
With the ingredients and their genetic blueprint now known, it may be possible to synthetically produce the proteins by inserting the genetic sequences into host organisms such as bacteria, plants or animals, she said. Once the pure proteins are harvested, a manufacturing challenge will be spinning them into silk fibers that have the same remarkable properties as spider spun silk. But several advances have recently been made in artificial spinning methods.
When spiders manufacture dragline silk, their silk glands produce a "gooey" slurry of the proteins needed, which are transported to the spinneret through a duct where the proteins interact and align to form the silk strands.
"The production of artificial silk is not quite there yet," Hayashi said. "Now, with the full length genes known and as we learn more about theses two proteins, hopefully we will have a better shot at mimicking nature."
Spider silks have some of the best mechanical properties of any known natural fibers, thus they are being considered in the improvement of a variety of products including surgical microsutures and specialty ropes. Dragline silk -- just one type of the seven different silks that an individual spider produces -- are used by spiders as the structural foundation of their webs and to support their body weight as they move about. The dragline silk of black widows is one of the strongest and toughest spider silks identified thus far.
Note: This story has been adapted from a news release issued by University of California - Riverside.
論文出處：
"Blueprint for a High-Performance Biomaterial: Full-Length Spider Dragline Silk Genes ", PLoS ONE, 2007, 2(6): e514.
http://www.plosone.org/article/fetchArticle.action?articleURI=info%3Adoi%2F10.1371%2Fjournal.pone.0000514
相關連結：
1. Spider Silk：http://www.chm.bris.ac.uk/motm/spider/page3.htm