In an article in the journal Proceedings of the National Academy of Science (PNAS) Uppsala researchers are now presenting results of experiments that contradict the theory.
Proteins govern nearly all chemical processes in the body's cells. A fundamental property of proteins is their ability to transfer signals – both within and between proteins. It is known, for example, that such signal transfer is vital to haemoglobin, which transports oxygen in the body. In that instance the mechanism has largely been clarified.
"But in other instances very little is known about the mechanisms or whether such signal transfer even occurs," says Per Jemth, who together with his research group at Uppsala University is studying whether signal transfer also occurs in small proteins.
Nearly ten years ago great attention was attracted by an article published in Science that described a method of demonstrating signal transfer in proteins by comparing their amino acid sequence. The authors recorded a statistical method of showing how certain parts of proteins change together through evolution, i.e. if a change had taken place in one part a change simultaneously took place in another part of the protein. One thus found a network of parts that seemed to belong together, and within this network signal transfer was deemed to take place.
But the Uppsala researchers saw several things that were not right about the results in the much discussed article, and by means of experiments they can now show that no more signals occur in this network than with other parts of the protein. They instead found, completely logically, that nearby parts of the protein interact more with each other than parts that are a long way apart.
"Our results thus question whether statistical methods can demonstrate signal transfer within proteins, and emphasise the importance of precise experiments to substantiate computer-based methods in protein chemistry," says Per Jemth.
The ability to predict proteins' function down to the smallest detail on the basis of their amino acid sequence is a goal that has preoccupied many researchers ever since human DNA became known. This study emphasises that experiments are needed to improve and refine the computerised methods currently in use.
"When theory, computer simulation and experiments provide the same answers the long-term goal has been attained, but there's still a long way to go."
Anneli Waara | alfa
Helping to Transport Proteins Inside the Cell
21.11.2018 | Albert-Ludwigs-Universität Freiburg im Breisgau
UNH researchers create a more effective hydrogel for healing wounds
21.11.2018 | University of New Hampshire
Innsbruck quantum physicists have constructed a diode for magnetic fields and then tested it in the laboratory. The device, developed by the research groups led by the theorist Oriol Romero-Isart and the experimental physicist Gerhard Kirchmair, could open up a number of new applications.
Electric diodes are essential electronic components that conduct electricity in one direction but prevent conduction in the opposite one. They are found at the...
Max Planck researchers revel the nano-structure of molecular trains and the reason for smooth transport in cellular antennas.
Moving around, sensing the extracellular environment, and signaling to other cells are important for a cell to function properly. Responsible for those tasks...
Researchers at the University of New Hampshire have captured a difficult-to-view singular event involving "magnetic reconnection"--the process by which sparse particles and energy around Earth collide producing a quick but mighty explosion--in the Earth's magnetotail, the magnetic environment that trails behind the planet.
Magnetic reconnection has remained a bit of a mystery to scientists. They know it exists and have documented the effects that the energy explosions can...
Biochips have been developed at TU Wien (Vienna), on which tissue can be produced and examined. This allows supplying the tissue with different substances in a very controlled way.
Cultivating human cells in the Petri dish is not a big challenge today. Producing artificial tissue, however, permeated by fine blood vessels, is a much more...
Faster and secure data communication: This is the goal of a new joint project involving physicists from the University of Würzburg. The German Federal Ministry of Education and Research funds the project with 14.8 million euro.
In our digital world data security and secure communication are becoming more and more important. Quantum communication is a promising approach to achieve...
19.11.2018 | Event News
09.11.2018 | Event News
06.11.2018 | Event News
21.11.2018 | Life Sciences
21.11.2018 | Power and Electrical Engineering
21.11.2018 | Life Sciences