A new technology for isolating and studying single proteins is paving the way for improved understanding of disease processes

Scientists have developed a new technology that has made it possible to isolate and study the behavior and changes over time of a single protein – 10,000 times thinner than a human hair.

The Nottingham Trent University team say the work – the first of its kind – allows them to see how the protein behaves in its natural environment and that it could help to better understand proteins associated with disease and how they might respond to certain therapies.

The research involves the use of a very high concentration of light which, when the beam is transmitted through a specially designed nanostructure, generates just the right amount of force to capture and hold a single protein in the liquid without damaging it.

The technology is able to detect how light is scattered, and researchers can analyze this unique data to reveal how the protein is behaving in real time.

The protein is studied in its natural liquid environment, as the team’s technique can mimic the body by changing factors such as salt concentration, pH or oxygen levels.

As a proof of concept, the researchers looked at ferritin, a protein in the blood that stores and releases iron, to prevent diseases associated with iron dysregulation, such as anemia.

During the study, they were able to distinguish between ferritin with and without iron – as the data revealed differences in their weight and movement – and even the point at which ferritin without iron began to capture and store iron.

They say the study has deepened the understanding of the mechanism of iron uptake by ferritin proteins, which may lead to new therapeutics for iron-related diseases.

Until now, ferritin studies have only been able to use ensemble measurements to quantify the characteristics of a large number of proteins, which provides limited information about their structural changes.

The researchers say that because the protein changes occur before the symptoms of the disease, their work could make it possible to identify and treat a number of diseases much earlier.

“To be able to see things beyond your eyesight, you first need the right technology. Our nanostructure allows us to observe proteins at the nanoscale,” said lead researcher Dr Cuifeng Ying from Nottingham Trent University’s School of Science and Technology.

She said: “This technique allows us to study the behavior of a single living protein by using a high-intensity light beam to capture, hold and study it in its own environment. You usually have to study many proteins together to see how a group responds.

“Many proteins are associated with disease; if we can see the root of the problem, then we can potentially treat them better and earlier.”

Arman Yousefi, Doctor of Philosophy. candidate at Nottingham Trent University and first author of this research said: “Scattered light provides us with a unique fingerprint to show us how the protein behaves. In the case of ferritin, we observed the protein’s stiff and relaxed states with and without iron, and even the process of collecting and storing iron from the environment.”

Mohsen Rahmani, NTU Professor of Engineering and Royal Society Wolfson Fellow, added: “This technology and technique gives us the potential to identify changes in proteins in relation to the onset and progression of disease. We can look at many proteins and see how they respond to different drugs. In the future, this breakthrough could play a key role in improving survival rates and reducing healthcare costs.

“Until now, there hasn’t been a tool that allows us to study proteins in this way without destroying them.

The study, which also involved the University of Nottingham and the Adolf Merkle Institute at the University of Friborg in Switzerland, is published in the journal Nano letters.