Method to ‘unboil eggs’ could slash food production costs

A team of chemists that have figured out a way to 'unboil' egg whites say that their development could dramatically reduce food production costs.

The method, which enables researchers to unlink and refold proteins in their original state is described in the journal ChemBioChem – with the authors behind the study suggesting that the innovation could dramatically reduce costs for medical treatments, food production and other segments of the $160 billion global biotechnology industry.

"We have invented a way to unboil a hen egg," explained Professor Gregory Weiss from the University of California at Irvine – who led the research. "In our paper, we describe a device for pulling apart tangled proteins and allowing them to refold. We start with egg whites boiled for 20 minutes at 90 degrees Celsius and return a key protein in the egg to working order."

Weiss noted that many researchers and commercial players involved in medicine or the production of foods struggle to efficiently produce or recycle valuable molecular proteins that have a wide range of applications but which frequently ‘mis-fold’ into structurally incorrect shapes when they are formed, rendering them useless.

"It's not so much that we're interested in processing the eggs; that's just demonstrating how powerful this process is," suggested the researcher. "The real problem is there are lots of cases of gummy proteins that you spend way too much time scraping off your test tubes, and you want some means of recovering that material."

Indeed, Weiss noted that older methods of recovering and recycling enzymes and proteins are expensive and time-consuming, explaining that the equivalent of dialysis at the molecular level must be done for about four days.

"The new process takes minutes," he said. "It speeds things up by a factor of thousands."

How to unboil an egg?

To re-create the clear and ‘raw’ lysozyme protein from an egg that has been boiled, Weiss and his colleagues added a urea substance that chews away at the whites, liquefying the solid material.

While this is half of the process; at the molecular level, the proteins are still intertwined, and ‘balled up’ into unusable masses, said the authors.

The scientists then used a vortex fluid device - a high-powered machine designed by Professor Colin Raston's laboratory at South Australia's Flinders University. Using the device, shear stress within thin, microfluidic films is applied to the small pieces of tangled protein, forcing them back into their untangled, proper form.

“This rapid refolding technique could significantly shorten times, lower costs, and reduce waste streams associated with protein expression for a wide range of industrial and research applications,” said the team, who added that the method “could transform industrial and research production of proteins."

Indeed, they said that the ability to quickly and cheaply re-form common proteins from yeast or E. coli bacteria could potentially streamline protein manufacturing and make medical treatments more affordable, while industrial cheese makers, farmers and others who use recombinant proteins could also achieve more ‘bang for their buck.’

According to the team, the University of California – Irvine has filed for a patent on the work, and its Office of Technology Alliances is working with interested commercial partners.

Source: ChemBioChem

Published online ahead of print, doi: 10.1002/cbic.201402427

“Shear-Stress-Mediated Refolding of Proteins from Aggregates and Inclusion Bodies”

Authors: Dr. Tom Z. Yuan, et al