• Project Lead
    Professor Michael Kamm

Project Details

Eastern Inflammatory Bowel Disease Gut Microbiota – The ENIGMA  II Study

Within the gut resides a vast ecosystem of bacteria, fungi and viruses, otherwise known as the gut microbiota. This ecosystem comprises 90 percent of the cells in our body. Our normal human cells therefore constitute only a minority of the cells in our body.

We are working with scientists to unravel the exact nature of these organisms in our gut, and the role they play in causing or curing disease. New molecular techniques are identifying previously unknown bacterial species. New insights are also emerging about the effect of diet on the gut bacteria and how this might affect gut inflammation.

The presence and function of the microbiota are essential to our wellbeing - these organisms perform a range of functions critical to development, growth, metabolic function, and protection from disease.  However, the gut microbiota is now also thought to play some role in the development of inflammatory bowel disease, obesity, arthritis, and allergic diseases.

Identifying particular bacteria that play a role in disease can have an enormous impact. For example, identification of the bacterium Helicobacter pylori by Australian Nobel prize-winning researchers led to the virtual eradication of stomach and bowel ulcer disease. That single observation was one of the key medical discoveries of the twentieth century.

Of a similar magnitude, discovery of the rotavirus as the commonest cause of childhood diarrhoea, by scientists at the Royal Children’s Hospital, Melbourne, together with the subsequent development of a vaccine, has had a huge impact on childhood illness and death worldwide. There are more discoveries to be made in this area.

The ENIGMA II Study (Eastern Inflammatory Bowel Disease Gut Microbiota) - is a collaboration with our colleagues at the Chinese University of Hong Kong and Frazer Institute at the University of Queensland.  This study combines basic science, dietetics and clinical science to form a unique and powerful research combination to address the role of the gut microbiota and diet in surging Crohn's disease prevalence.  The ENIGMA II Study is making fundamental discoveries about the key microbial organisms and related dietary factors that cause and contribute to the development of IBD in the West, and in the East (Hong Kong and China) where IBD incidence is rapidly increasing.

The ecosystem within our gut is central to our well-being, but also to the development of many gut and non-gut disorders. Its scientific exploration is leading to new therapies and cures.


Professor Michael Kamm – Group Leader

Dr. Amy Hamilton – Clinical Scientist

Ms. Annalise Stanley – Research Nurse

Dr. Gina Trakman – Research Dietitian

Dr. Amy Wilson-O’Brien – Clinical Scientist


Chinese University of Hong Kong:
Ms. Jessica Ching
Ms. Winnie Lin
Professor Siew Ng
Mr. Leo Or
Professor Joseph Sung
Professor Jun Yu
Dr. Wendy Zhang

The University of Queensland – Diamantina Institute
Professor Mark Morrison
Mr. Seungha Kang
Mr. Jing Jie Teh


The Leona M. and Harry B. Helmsley Charitable Trust

Research Publications

Novel strain-level resolution of Crohn's disease mucosa-associated microbiota via an ex vivo combination of microbe culture and metagenomic sequencing.

Teh JJ, Berendsen EM, Hoedt EC, Kang S, Zhang J, Zhang F, Liu Q, Hamilton AL, Wilson-O'Brien A, Ching J, Sung JJY, Yu J, Ng SC, Kamm MA, Morrison M.ISME J. 2021 Nov;15(11):3326-3338. doi: 10.1038/s41396-021-00991-1. Epub 2021 May 25.PMID: 34035441

Processed Food as a Risk Factor for the Development and Perpetuation of Crohn's Disease-The ENIGMA Study.

Trakman GL, Lin WYY, Hamilton AL, Wilson-O'Brien AL, Stanley A, Ching JY, Yu J, Mak JWY, Sun Y, Niu J, Miao Y, Lin X, Feng R, Chen M, Shivappa N, Hebert JR, Morrison M, Ng SC, Kamm MA.Nutrients. 2022 Sep 2;14(17):3627. doi: 10.3390/nu14173627.PMID: 36079885

Childhood antibiotics as a risk factor for Crohn's disease: The ENIGMA International Cohort Study.

Mak JWY, Yang S, Stanley A, Lin X, Morrison M, Ching JYL, Niu J, Wilson-O'Brien AL, Feng R, Tang W, Hamilton AL, Or L, Trakman GL, Lin WYY, Sung JJY, Chen MH, Mao Y, Kamm MA, Ng SC.JGH Open. 2022 Jun 1;6(6):369-377. doi: 10.1002/jgh3.12755. eCollection 2022 Jun.PMID: 35774350

Development and Validation of Surveys to Estimate Food Additive Intake.

Trakman GL, Lin W, Wilson-O'Brien AL, Stanley A, Hamilton AL, Tang W, Or L, Ching J, Morrison M, Yu J, Ng SC, Kamm MA.Nutrients. 2020 Mar 19;12(3):812. doi: 10.3390/nu12030812.PMID: 32204474

Research Group

Michael Kamm

School Research Themes

Key Contact

For further information about this research, please contact the research group leader.

Department / Centre



St Vincent's Hospital

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