How spider silk avoids hungry bacteria

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