Though often depicted as static blobs, proteins are more like collections of balls and springs, constantly in motion, and their endless atomic twitching conveys information about their organization, Zanni says. Infrared laser beams can detect the minute vibrations and identify characteristic patterns to deduce protein structures.
A few years ago, Zanni's team built the first device capable of designing infrared laser beams with a computer. The team has now simplified and speeded up the process with an automated version of the 2-D IR technique. As described in the current study, they obtained a single structural scan of hIAPP in less than a second - more than 500 times faster than previously possible.
The speed is crucial for trying to understand a dynamic process like hIAPP mis-folding, Zanni says.
The group now plans to capture series of snapshots during individual folding reactions to identify multiple phases as the proteins convert from an unordered mishmash into flat sheets, then coil into fibers.
"No matter how fast they're moving, we can take pictures of them," says Zanni. Without their automated method, he says, such experiments would be nearly impossible.
The technique also has potential application in other human diseases that involve protein mis-folding, such as Alzheimer's and Huntington's diseases.
At this time, however, he says the automation of the device itself is a tremendous achievement. "In time, automated 2-D IR spectroscopy will become a common analytical technique, widely available in university and industrial research laboratories around the world."
Source:University of Wisconsin-Madison