University of California, Irvine, chemistry and molecular biology professor Gregory Weiss wanted to figure out how to refold lab-created proteins associated with cancer. "The problem is when we tried to produce cancer-associated proteins... often times the proteins come out as a jumbled mess," Weiss said. "It kind of looks like boiled eggs... When that happens, we sigh deeply."
It can take days, even weeks, for scientists to tease out those gunked-up proteins that are stuck to the edges of test tubes. Until recently, those proteins were unpacked using dialysis, a method that's been around for more than a century.
So Weiss when visited Colin Raston’s South Australia’s Flinders University laboratory and saw his high-powered, vortex-fluid device that essentially pulls things apart, Weiss thought: why not pull proteins apart?
A graduate student brought one of Raston's machines back to Weiss's lab in California, and the chemist set himself to testing it out. "I wanted to demonstrate the power of this technique," Weiss said.
The saying "you can't unscramble an egg" came to mind; Weiss thought he'd set about proving that wrong.
So they took an egg (cost: $2 for a dozen), and separated the yolk from the white, Julia Childs-style. The whites were boiled for 20 minutes at 90 degrees Celsius, which, yuck. "At the end they're rock hard," Weiss said.
The egg whites' proteins had changed shape, but the proteins themselves remained intact -- much like misshapen cancer-associated proteins. So Weiss set about unfolding those egg white proteins back into shape, by first dissolving the boiled egg whites overnight in an urea chemical solution.
Then, he took the mixture, put it into the vortex fluid device, and the whites went for a high-speed, five-minute spin. As the proteins brush up against the test tube walls, the high shear force generated is enough to pull the proteins.
"They're like little elastic bands," Weiss said. "This stretches and unstretches them, and gives them their shape back."
The result was a clear solution that looked just like diluted egg whites. At a molecular level, researchers looked at the protein lysozyme (a pretty important protein in giving eggs their antibacterial property). The process of diluting the egg whites and sticking them in the machine restored lysozyme back to about 85 percent of pre-boiled activity, Weiss said.
"The fundamental principle that we demonstrated was this idea that the proteins have changed their shape but they haven't changed their bonding patterns, their connectivity," Weiss said.
And that can be a big deal. Weiss discussed some of those application in depth during a Reddit AMA. Rather than spending days and weeks putting certain misshapen proteins back together, people in laboratories may be able to stick solutions into 2-by-2 foot machines and be done with it just minutes later, so they can get back to the work of developing cancer treatments.