Research led by the University of Limerick has revealed the complex structure of a unique enzyme found in all living cells.The enzyme ‘cytochrome c oxidase/cytochrome c complex’ provides a vital function in the conversion of oxygen to water and energy within all living cells. Understanding the structure and function of this enzyme will aid scientists understanding of many serious genetic disorders including Leigh Syndrome, MELAS (mitochondrial myopathy, encephalopathy, lactic acidosis and stroke-like episodes), and AISA (acquired idiopathic sideroblastic anemia).

Lead researcher, Dr Tewfik Soulimane, University of Limerick explains the significance of this research; “These findings will have a profound impact on basic and applied sciences through the understanding of cellular respiration and energy conservation as well as genetic disorders including Leigh syndrome, MELAS and AISA.  The structure will help our understanding of these diseases and subsequently will aid researchers in the rational design and discovery of drugs that can help alleviate their effects.”

This is the first membrane protein structure solved by an Irish-based research group and the findings have been published by leading international science journal, Nature.

This enzyme has long been known to provide a central function in cellular respiration and energy conservation. However, until now, the enzyme’s make-up and function has not been fully understood. In cellular respiration, oxygen is transferred through the blood stream and stored in the muscle to be finally reduced to water in mitochondria, the cellular energy powerhouse. This final reaction relies on cytochrome c oxidase to take place.

As well as being the first protein structure solved by an Irish-based research group, it is also the largest membrane protein that has been crystallised to date using a novel crystallisation technique discovered by Landau and Rosenbusch at the Biocentre in Basel, Switzerland in 1996 and further developed to a high standard of miniaturisation and robotics by Professor Martin Caffrey, TCD.

‘Structural insights into electron transfer in caa₃-type cytochrome c oxidase’ was authored by Joseph A Lyons (UL), Orla Slattery (UL), David Aragão (TCD), Tewfik Soulimane* (UL) and Martin Caffrey* (TCD) and published in Nature– see link: http://www.nature.com/nature/journal/vaop/ncurrent/full/nature11182.html

This research was funded by Science Foundation Ireland (SFI) and undertaken at the Department of Chemical and Environmental Sciences and the Materials and Surface Science Institute (MSSI) at the University of Limerick.