Edward Egelman, a professor of biochemistry and molecular genetics, studies ancient single-cell organisms found in some of Earth’s most extreme environments—like acid hot springs—that are hostile to most forms of life. In such inhospitable conditions, how do “extremophiles” survive?

While studying one such organism, Sulfolobus islandicus, Egelman and a team of researchers examined the long, hairy appendages called pili that, Rapunzel-like, extend from the cell to many times its length. The pili, says Egelman, “were indestructible using the normal lab techniques we have for taking things apart”—including boiling in lye. What extraordinary substance, they wondered, could provide such impenetrable protection? 

After nearly a year of work, they found an unexpected answer: sugars.  “There was just a massive amount of sugars chemically bound to the surface of these filaments,” says Egelman, a discovery that—“as far as we know,” he emphasizes—has not yet been observed elsewhere in nature. 

How the organism goes about assembling its sugary suit of armor, “we don’t know anything about,” Egelman says. “It’s not simply ‘Shake ’n Bake,’ where you roll these things in sugars.”

And what is the significance of this finding? While Egelman notes there certainly could be long-term practical applications—perhaps in these sugar-shielded pili will be found the secret to indestructible new materials—what interests him is not the answers, but the questions.  “The most important takeaway,” he says, “is that there is so much about life on Earth that we still don’t understand.”