Tracking the Chemical Footprints of Bacteria

9 March, 2017

We all know that green leafy vegetables, seafood, meat, dairy, cereals and even mushrooms, almonds and vegemite are all healthy for us. One essential ingredient in them is vitamin B2 (riboflavin) that enriches our immune system. But did you know that bacteria in our bodies also make this vitamin?

Scientists at the Universities of Queensland, Melbourne and Monash recently learned that when bacteria produce this vitamin, they leave behind a trail of chemical footprints that are invisible under microscopes and vanish in minutes. Two chemists at the University of Queensland’s Institute for Molecular Bioscience, Dr Jeff Mak and Dr Ligong Liu, have now made these chemicals in a testube.

Dr Mak said “Certain white blood cells in our immune system act like sniffer dogs in finding these footprints and chasing after bacteria to destroy them”. Dr Liu said “Our immune cells can find just a few molecules in a trillion (1,000,000,000,000) of these chemical footprints”. “By learning how to make these trace chemicals from bacteria, scientists around the world now have new tools to find even traces of infection in our body and new clues to fight disease”, added team leader Professor David Fairlie.

The work published this week in Nature Communications was supported by the ARC Centre of Excellence in Advanced Molecular Imaging and the National Health and Medical Research Council of Australia.

Why was half the Fairlie Group present at the Australian Synchrotron in Melbourne this month?

26 October, 2014

The new ARC Centre of Excellence in Advanced Molecular Imaging is integrating the research activities of physicists, structural biologists, chemists and immunologists in order to better understand the molecular basis of immunity and disease. The Australian Synchrotron is providing the power necessary to see into the secrets of immunology that have to date evaded researchers in the field. Our cooperative studies can give a more detailed picture on how the immune system works at the atomic, molecular, macromolecular, cellular and animal levels and this is essential in 21st century efforts to combat major diseases.

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New National Health And Medical Research Council Grants

17 October, 2014

Congratulations to Dr Abishek Iyer, Dr Rink-Jan Lohman, Dr Jacky Suen and Prof David Fairlie from the Fairlie Group who are chief investigators on three new research grants:

(1) Targeting Protease Activated Receptor 2 In Immunometabolism And Obesity

(2) Downsizing A Human Protein To Modulate Inflammatory Diseases

(3) Modulating Inflammatory and Fibrogenic Pathways in Kidney Disease using a novel antagonist of     Protease-Activated-Receptor-2

Launch of the ARC Centre of Excellence in Advanced Molecular Imaging

15 October, 2014

Researchers from the Fairlie Group travelled to Melbourne for the official launch of this new ARC Centre of Excellence at Monash University and for a mini-symposium at the Australian Synchrotron involving the Centre’s researchers.  This begins a seven year collaboration between physicists, chemists, structural biologists and immunologists aimed at understanding the molecular basis of immunity.

http://www.uq.edu.au/news/article/2014/10/imaging-centre-unravel-secrets-of-immune-system

PhD Student News

1 October, 2014

Congratulations to PhD student Daniel Nielsen for winning a Graduate School International Travel Award from a field of over 100 applicants. Dan will use the award to present at the 249th national meeting of the American Chemical Society in Denver, Colorado and to visit collaborators at Pfizer in Boston.

Congratulations to new PhD student Yuhong Jiang for winning a Chinese Scholarship Council award to commence studies at the University of Queensland.

Two recent publications recommended by F1000

Two of our newest 2014 publications in American Chemical Society journals have been selected for F1000Prime after recommendations (as being of special significance in their fields) by members of the Faculty of 1000.

Cyclic Penta- and Hexa- Leucine Peptides without N-Methylation Are Orally Absorbed” American Chemical Society Medicinal Chemistry Letters, 2014 (DOI: 10.3410/f.718535035.793498861) by Dr Tim Hill and colleagues. Faculty of 1000Prime citation (http://f1000.com/prime/718535035).

Stereoelectronic Effects Dictate Molecular Conformation and Biological Function of Heterocyclic Amides” Journal of the American Chemical Society, 2014 (DOI: 10.3410/f.718522891.793498839) by Dr Robert Reid and colleagues. Faculty of 1000Prime citation (http://f1000.com/prime/718522891).

Immune sentries protect gut from bugs by sensing vitamins

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Dr Ligong Liu and Dr Jeffrey Mak

Australian researchers have identified a biochemical key that alerts immune cells to the presence of bacteria and fungi, which could lead to new ways of diagnosing and treating diseases such as inflammatory bowel disease, peptic ulcers and even infections like tuberculosis.

The discovery, made by scientists from the Universities of Queensland, Melbourne, Monash and Cork, provides a starting point for understanding a human’s first line of immune defence and what causes it to go wrong in disease.

The team had previously found that a type of immune cell, known as mucosal-associated invariant T cells (MAITs), could detect molecules produced by bacteria and fungi when manufacturing vitamin B2, also known as riboflavin.

Bacteria synthesise vitamin B2 for their growth whereas humans are unable to make this vitamin.

The researchers have now pinpointed the exact chemicals that activate these special human immune cells, which act as red flags to the immune system.

Professor David Fairlie, from UQ’s Institute for Molecular Bioscience, said this finding may be very important for understanding the body’s reaction to some bacterial infections.

“Essentially this is a way of sensing the presence of bacteria and mounting an immune response, without interfering with nutrition,” Professor Fairlie said.

“This may be a valuable clue to previously unknown mechanisms of immunity and possibly disease pathology, and could lead to entirely new drug development strategies.

He acknowledged Dr Ligong Liu and Dr Jeff Mak, also from UQ’s Institute for Molecular Bioscience, who synthesised and isolated the unstable chemicals that trigger activation of these T cells.

Other senior authors on the paper, published overnight in world-leading scientific journal Nature, were Professor Jim McCluskey from The University of Melbourne and Professor Jamie Rossjohn from Monash University.

“This is an excellent example of how collaborative research in Australia can bring groups with expertise in different areas together to make significant advances,” Professor McCluskey, Deputy Vice-Chancellor (Research) of The University of Melbourne, said.

The work is an early win for the recently announced Australian Research Council Centre of Excellence in Advanced Molecular Imaging.

“We want to unravel the complex molecular interactions that define how we fight disease,” Professor Rossjohn said.

“This remarkable research collaboration shows us how to do it.”

Media contact: IMB Communications Manager Bronwyn Adams, 0418 575 247, 07 3346 2134,b.adams@imb.uq.edu.au