保护与存活：饥饿的细菌不吃蜘蛛丝，何以如此？_风闻

【来源龙腾网】

正文原创翻译：

Tougher than any fibre made by humans and extraordinarily good at transmitting vibrations to the predators that weave it, spider silk has been a source of inspiration for the development of everything from scaffolding for regenerating bones to bulletproof vests, remote sensors and noise reducers.

蜘蛛丝比任何人造纤维都更加强韧，并能很好地将振动传递给织网的捕食者。其成为了许多事物发展的灵感来源：从再生骨头的支架到防弹背心、遥感器和降噪设备。

Yet one of its most remarkable attributes, its resistance to decay, has received little attention. Some researchers speculate that spider silk keeps hungry bacteria at bay by being laced with antibiotics.

然而蜘蛛丝最奇特的特征之一——抗腐蚀，却未被重视。一些研究人士推测饥饿的细菌不腐蚀蜘蛛丝是因为其中含有抗生素。

But work by Wang Pi-Han and Tso I-Min at Tunghai University, in Taiwan, published in the Journal of Experimental Biology, suggests this is not the case.

但台湾东海大学的汪碧涵和卓逸民发表于《实验生物学期刊》上的文章表明事实并非如此。

Rather, silk manages to avoid being eaten by locking the nutrients it contains behind an impenetrable barrier. Spider silk is made of proteins that ought to be attractive to microbes.

相反，蜘蛛丝将所含营养锁在无法穿透的屏障内，以此避免被细菌腐蚀。蜘蛛丝是由微生物喜爱的蛋白质构成的。

原创翻译：龙腾网 http://www.ltaaa.com 翻译：mud_99 转载请注明出处

Moreover, because webs are often built in environments, like forests and bogs, that are rife with these bugs, there should be ample opportunities for bacteria to settle on the strands and feast. Remarkably, This does not seem to happen.

另外，因为蜘蛛网常常生长于森林沼泽这样充满虫子的环境，所以细菌有充足的机会栖居其上、尽情饱餐。令人惊异的是，这一切似乎并未发生。

Dr Wang and Dr Tso were curious about how spiders manage this. They began their investigation by putting bacteria and spider silks together in laboratory conditions perfect for bacterial growth. They worked with silk strands collected from three species of spider that build their webs in different environments, and set these down on nutrient-rich plates. Each plate had one of four bacterial species growing on it.

这是如何实现的？王博士和陶博士感到十分好奇。他们对此展开了研究，将细菌和蜘蛛丝放在一起，置于适宜细菌生长的实验室条件下。从在不同环境中织网的三种蜘蛛处收集了蜘蛛丝，将它们放进富含营养的培养皿中。共四种细菌，每个培养皿中都有一种细菌在蜘蛛丝上生长。

The team then used microscopes to monitor the behaviour of the bacteria over the course of 24 hours. After repeating the experiment three times, they found that the bacteria never fed on the silks.

之后这个团队用显微镜观察24小时内细菌的行为。在重复该实验三次之后，它们发现细菌从未腐蚀蜘蛛丝。

They also found, however, that the strands were not immune to having bacteria grow over and around them—suggesting that those strands were not laced with antibiotics.

然而，它们也发现细菌在蜘蛛丝上和其周围得以生长，表明蜘蛛丝内并无抗生素。

The two researchers then tried growing their bacteria directly on silk strands, by providing them with a range of nutrient supplements.

其后，两位研究员为蜘蛛丝提供了一些营养补充剂，尝试着直接让细菌生长在蜘蛛丝上。

Only one of these supplements, nitrogen, encouraged consumption of the silk.

只有一种补充剂——氮——让细菌以蜘蛛丝为食。

When the strands were lathered in a nitrogen-rich solution, bacteria ate them. Without nitrogen, they were held at bay.

当蜘蛛丝被涂上富含氮的溶液时，细菌便以蜘蛛丝为食。如果没有氮，细菌就不吃。

This is odd, because proteins (of which silk is made) are, themselves, rich in nitrogen. That led Dr Wang and Dr Tso to conclude that the antibacterial properties of spider silk are caused not by any sort of antibiotic but, rather, the structure of the silk itself.

这很奇怪。因为构成蜘蛛丝的蛋白质自身就富含氮。王博士和陶博士于是得出结论，蜘蛛丝的抗菌特性并不是因为其中含有抗生素，而是由于蜘蛛丝自身的结构。

Natural sextion, it seems, has driven spider silk to store the proteins it is composed of behind a layer made impenetrable by its physical rather than its chemical structure.

自然选择似乎驱使蜘蛛丝将构成自身的蛋白质储存于一个表层之后，因其物理结构而非化学结构而无法穿透。

What, exactly, that structure is the two researchers have yet to determine. Once it has been elucidated, though, the discovery should pave the way for artificial antibacterial materials that do not use antibiotics to keep the bugs away.

这一结构具体是什么，两位研究人员还没有定论。但是，一旦将其阐明，这一发现将会为人造抗菌物质铺平道路，不必使用抗生素就可以使细菌远离。

译者补充：

1. 所提论文见于《实验生物学杂志》2019年10月23日，222卷，20期。论文题目为Nitrogen inaccessibility protects spider silk from bacterial growth。doi: 10.1242/jeb.214981

2. 汪碧涵教授邮箱：[email protected]；卓逸民教授邮箱：[email protected]。