e. coli

A whale’s skin is easily glommed up with barnacles, algae, bacteria and other sea creatures, but sharks stay squeaky-clean. Although these parasites can pile onto a shark’s rippled skin too, they can’t take hold and thus simply wash away. Now scientists have printed that pattern on an adhesive film that will repel bacteria pathogens from hospitals and public restrooms.

Images of the Virgin Mary have appeared on grilled cheese sandwiches, trees and now in a petri dish. But that last appearance was no heavenly manifestation. It was a sign that Christopher Voigt’s photographic bacteria were working.

Generally, DNA is only good for preserving and passing on blueprints for making organisms. However, scientists at MIT and Boston University have altered E. coli DNA to perform another function within the cell, like basic computing. Essentially, they've taught E. coli to count.

We've all heard of the five-second rule when having dropped food on the floor—if you pick it up before five seconds have passed, it's safe to eat. In recent years, scientists have put that folk wisdom to the test and the results fell somewhere in the middle. If bacteria are present on the floor, researchers found that five seconds is plenty of time for it to attach to your food. However, most floors harbor very little bacteria, so unless you're unlucky enough to drop your toast on a tiny patch of e. coli, you'll probably be fine to eat it. If you were to drop that bread on your keyboard, though, that's another story. You'd maybe want to back away slowly and reach for the nearest tongs.

It could be an aerial photo of an oil spill: liquid spheres pooling, oozing, dwarfing a bedraggled landscape. I half expect to zoom in on poisoned seal pups or waterbirds dragging their oil-soaked feathers. But the scene is microscopic. The landscape is made of E. coli. And whats happening is exactly the opposite of what it seems. The little bugs arent drowning in fuel. Theyre making it.