The findings, published today [16 October 2008] in Science Express, are important because there are hundreds of transporter proteins in the body and understanding their structure and how they work will help scientists design the next generation of drugs to treat illness and disease.
“Transporter proteins are very difficult to study,” says Professor Peter Henderson of the University of Leeds. “However, in Leeds we developed methods to maximise their expression in bacteria, and purify them very carefully so they retain their biological activity. We could then maintain a ‘pipeline’ to supply them to experts in a technique called protein crystallography, which requires very high intensity x-rays, available, for example, at the Diamond Light Source national synchrotron facility in Oxfordshire and the European Synchrotron Radiation Facility (ESRF) in Grenoble.”
At Diamond, co-author Professor So Iwata and colleagues from Imperial College London’s Department of Life Sciences imaged the transporter protein Microbacterium hydantoin permease (Mhp1) - which lives in the oily membrane that surrounds bacterial cells – transporting molecules of hydantoin across its otherwise impermeable cell membrane. Once inside the cell, these molecules are converted to useful amino acids, which are of commercial importance, as they are used for food and drink supplements and to make pharmaceuticals.
The structure of Mhp1 was analysed both before and after it had taken in a hydantoin molecule from outside the cell. The researchers saw that the Mhp1 protein opens up on its outer-facing side, allowing the hydantoin molecule to move inside. Once the hydantoin is bound, the pathway closes behind it, ensuring that no other substances are let in. The inward-facing side then opens to release the hydantoin into the cell.
Commenting on the significance of the discovery, Professor Iwata says: “Our research has revealed the detailed molecular function of an important membrane protein. We now know how the protein facilitates the movement of hydantoin across the cell membrane without letting any other substances through at the same time. This mechanism is likely to be shared by many cell membrane transport proteins, including those in the human body, so this is an important step forward in our understanding of the fundamental processes which occur in our cells.”
The research was funded in the UK by the BBSRC and the EU and carried out in collaboration with scientists from Japan and Iran.
The function of Mhp1 was initially discovered during a two year visit to Leeds – which began in 2000 - by a Japanese researcher, Dr Suzuki, from Ajinomoto Inc. This work was patented in Japan and the USA.
Professor Peter Henderson adds: “We hope now to gain sufficient detail of the intimate structure of many transporter proteins to help chemists and industrial sponsors to design and develop drugs to manipulate their activities and treat a variety of diseases.”
Clare Elsley | alfa
Multi-institutional collaboration uncovers how molecular machines assemble
02.12.2016 | Salk Institute
Fertilized egg cells trigger and monitor loss of sperm’s epigenetic memory
02.12.2016 | IMBA - Institut für Molekulare Biotechnologie der Österreichischen Akademie der Wissenschaften GmbH
A multi-institutional research collaboration has created a novel approach for fabricating three-dimensional micro-optics through the shape-defined formation of porous silicon (PSi), with broad impacts in integrated optoelectronics, imaging, and photovoltaics.
Working with colleagues at Stanford and The Dow Chemical Company, researchers at the University of Illinois at Urbana-Champaign fabricated 3-D birefringent...
In experiments with magnetic atoms conducted at extremely low temperatures, scientists have demonstrated a unique phase of matter: The atoms form a new type of quantum liquid or quantum droplet state. These so called quantum droplets may preserve their form in absence of external confinement because of quantum effects. The joint team of experimental physicists from Innsbruck and theoretical physicists from Hannover report on their findings in the journal Physical Review X.
“Our Quantum droplets are in the gas phase but they still drop like a rock,” explains experimental physicist Francesca Ferlaino when talking about the...
The Max Planck Institute for Physics (MPP) is opening up a new research field. A workshop from November 21 - 22, 2016 will mark the start of activities for an innovative axion experiment. Axions are still only purely hypothetical particles. Their detection could solve two fundamental problems in particle physics: What dark matter consists of and why it has not yet been possible to directly observe a CP violation for the strong interaction.
The “MADMAX” project is the MPP’s commitment to axion research. Axions are so far only a theoretical prediction and are difficult to detect: on the one hand,...
Broadband rotational spectroscopy unravels structural reshaping of isolated molecules in the gas phase to accommodate water
In two recent publications in the Journal of Chemical Physics and in the Journal of Physical Chemistry Letters, researchers around Melanie Schnell from the Max...
The efficiency of power electronic systems is not solely dependent on electrical efficiency but also on weight, for example, in mobile systems. When the weight of relevant components and devices in airplanes, for instance, is reduced, fuel savings can be achieved and correspondingly greenhouse gas emissions decreased. New materials and components based on gallium nitride (GaN) can help to reduce weight and increase the efficiency. With these new materials, power electronic switches can be operated at higher switching frequency, resulting in higher power density and lower material costs.
Researchers at the Fraunhofer Institute for Solar Energy Systems ISE together with partners have investigated how these materials can be used to make power...
16.11.2016 | Event News
01.11.2016 | Event News
14.10.2016 | Event News
02.12.2016 | Medical Engineering
02.12.2016 | Agricultural and Forestry Science
02.12.2016 | Physics and Astronomy