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
For a chimpanzee, one good turn deserves another
27.06.2017 | Max-Planck-Institut für Mathematik in den Naturwissenschaften (MPIMIS)
New method to rapidly map the 'social networks' of proteins
27.06.2017 | Salk Institute
An international team of scientists has proposed a new multi-disciplinary approach in which an array of new technologies will allow us to map biodiversity and the risks that wildlife is facing at the scale of whole landscapes. The findings are published in Nature Ecology and Evolution. This international research is led by the Kunming Institute of Zoology from China, University of East Anglia, University of Leicester and the Leibniz Institute for Zoo and Wildlife Research.
Using a combination of satellite and ground data, the team proposes that it is now possible to map biodiversity with an accuracy that has not been previously...
Heatwaves in the Arctic, longer periods of vegetation in Europe, severe floods in West Africa – starting in 2021, scientists want to explore the emissions of the greenhouse gas methane with the German-French satellite MERLIN. This is made possible by a new robust laser system of the Fraunhofer Institute for Laser Technology ILT in Aachen, which achieves unprecedented measurement accuracy.
Methane is primarily the result of the decomposition of organic matter. The gas has a 25 times greater warming potential than carbon dioxide, but is not as...
Hydrogen is regarded as the energy source of the future: It is produced with solar power and can be used to generate heat and electricity in fuel cells. Empa researchers have now succeeded in decoding the movement of hydrogen ions in crystals – a key step towards more efficient energy conversion in the hydrogen industry of tomorrow.
As charge carriers, electrons and ions play the leading role in electrochemical energy storage devices and converters such as batteries and fuel cells. Proton...
Scientists from the Excellence Cluster Universe at the Ludwig-Maximilians-Universität Munich have establised "Cosmowebportal", a unique data centre for cosmological simulations located at the Leibniz Supercomputing Centre (LRZ) of the Bavarian Academy of Sciences. The complete results of a series of large hydrodynamical cosmological simulations are available, with data volumes typically exceeding several hundred terabytes. Scientists worldwide can interactively explore these complex simulations via a web interface and directly access the results.
With current telescopes, scientists can observe our Universe’s galaxies and galaxy clusters and their distribution along an invisible cosmic web. From the...
Temperature measurements possible even on the smallest scale / Molecular ruby for use in material sciences, biology, and medicine
Chemists at Johannes Gutenberg University Mainz (JGU) in cooperation with researchers of the German Federal Institute for Materials Research and Testing (BAM)...
19.06.2017 | Event News
13.06.2017 | Event News
13.06.2017 | Event News
27.06.2017 | Power and Electrical Engineering
27.06.2017 | Information Technology
27.06.2017 | Physics and Astronomy