Study reveals how ulcer-inducing bacteria survive in the stomach

Scientists at The University of Western Australia, in collaboration with researchers at Imperial College London and Perth-based biotech Ondek Pty Ltd, have revealed new insights into the structure of an important biomolecule in Helicobacter pylori, the bacterium that causes stomach ulcers.

H. pylori,
discovered by UWA Professor Barry Marshall and Emeritus Professor Robin Warren, infects the human stomach and causes ulcers. Professor Marshall and Dr Warren were awarded the 2005 Nobel Prize for Medicine and Physiology for their discovery.

The latest UWA-led research, recently published inPLOS Pathogens, reveals the structure and enzymes responsible for the synthesis of the lipopolysaccharide. This biomolecule covers the entire surface of the bacterium like a shield and has unique properties compared to most other bacteria in that the molecule promotes lifelong infection by helping the bacterium evade the host’s natural immune system.

“Even though this information has been known for some time, the precise structure and the enzymes that the bacterium uses to build it have not been fully understood,” Professor Marshall said.

“Now that the enzymes involved in the synthesis have been found, opportunities in developing compounds that prevent the molecule from being formed could lead to new strategies to treat H. pylori infections.”

Co-author and chemical biologist Associate Professor Keith Stubbs, from UWA’s School of Molecular Sciences, said the research team was ideally placed to explore new treatment options.

“The team is now investigating which enzymes are the best targets and new compounds are being developed as potential therapeutics,” Associate Professor Stubbs said.

“Now we know the structure, we’re looking at how the biomolecule assists the bacterium in surviving in the stomach.”

The study was supported by funding from the National Health and Medical Research Council, Biotechnology and Biological Sciences Research Council, the Wellcome Trust, Australian Research Council, West China Hospital Sichuan University, UWA and the Ada Bartholomew Medical Research Trust. Professor Marshall founded biotech company Ondek Pty Ltd in 2006 to develop a range of therapeutics including products to treat allergic disorders.

Image credit: Luke Marshall

Media references

Professor Barry Marshall (UWA School of Biomedical Sciences)                        (+61 8) 6457 4815

Associate Professor Keith Stubbs (UWA School of Molecular Sciences)              (+61 8) 6488 2725

David Stacey (UWA Media and PR Manager)                      (+61 8) 6488 3229 / (+61 4) 32 637 716

The University of Western Australia