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Joseph Lyons receives The Young Investigator Award at Diamond Light Source

Joseph Lyons receives the award in recognition of the work carried out during his PhD studies on the development of a lipid mediated crystallisation method and its application to membrane proteins, which involved extensive use of the I24 beamline at Diamond Light Source. In addition to the honour of winning the award, Joseph Lyons receives GBP500.

Joseph Lyons (left) receives The Young Investigator Award at Diamond Light Source

The Diamond Young Investigator of the Year Award is given to the person with the most outstanding contribution to research involving synchrotron light and is sponsored by the Diamond Light Source located in Oxfordshire, UK. It is only the second time that the award is given.

Description of the PhD project

Joseph Lyons’ carried out his PhD studies in the Research Group of Prof. Martin Caffrey at the University of Limerick and later at Trinity College Dublin. The work centered on the development of a lipid mediated crystallisation method and its application to membrane proteins. Specific to this award, the protein in question is the multi-subunit respiratory enzyme, cytochrome c oxidase, an essential enzyme in aerobic respiration. 

The project was carried out in collaboration with Prof. Tewfik Soulimanewho provided the caa3-type cytochrome oxidase which was isolated natively from Thermus thermophilus. The enzyme serves to split the two oxygen atoms of an oxygen molecule apart, using separately donated electrons and protons, in a tightly regulated process that produces water and at the same time the derived energy from the reaction is preserved in the form of a chemical and an electrical (proton) gradient across the membrane. This gradient is used downstream for a variety of processes, chief amongst them the production of chemical energy in the cell, i.e., ATP synthesis. 

While the structure of cytochrome c oxidase is largely known, of particular note in this work is a signature sequence motif close to the active site that is poised for controlling oxygen reduction and proton pumping, thus painting an alternative picture for how proton gating occurs in this cytochrome oxidase. The work also provides the first crystallographic snapshot of a cytochrome c/cytochrome c oxidase complex, a complex which has resisted crystallographic invesigations due to the transient nature of their interaction. This complex is covalently locked in caa3-type cytochrome oxidase and allowing for the facile determination of the electron transport pathway through which electrons are shuttled from cytochrome c to the active site.

The project involved the generation of micro-crystals of the protein which were systematically screened at Diamond Light Source, UK and the Advanced Photon Source, USA. These facilities offered complementary and state of the art instrumentation which made it possible to collect data from such small challenging and fragile samples.


Structural insights into electron transfer in caa3-type cytochrome oxidase
Joseph A. Lyons, David Aragão,  Orla Slattery,  Andrei V. Pisliakov,  Tewfik Soulimane & Martin Caffrey
http://www.nature.com/nature/journal/vaop/ncurrent/full/nature11182.html

The research was funded by Science Foundation Ireland, National Institutes of Health, EU FP7 and Marie Curie Actions.


Diamond Light Source

Photo: Diamond Light Source

About Diamond Light Source

Diamond Light Source is the UK’s national synchrotron facility, located at the Harwell Science and Innovation Campus in Oxfordshire. By accelerating electrons to near light-speed, Diamond generates brilliant beams of light from infra-red to X-rays which are used for academic and industry research.

 


More information

Postdoctoral Fellow Joseph A. Lyons
Department of Molecular Biology
Aarhus University, Denmark
lyons@mb.au.dk