19 September 2006

A new University of Queensland study aims to improve understanding of a remarkable organism which is an important cause of diarrhoea in animals and humans.

Dr Darren Trott, a lecturer in UQ’s School of Veterinary Science, has received a $55,000 UQ Foundation Research Excellence Award to study the intestinal spirochaete Brachyspira pilosicoli, a snake-like bacterium inhabiting the colon.

“This organism has consistently been identified as one of the major disease-causing agents (pathogens) leading to colitis in pigs and poultry,” Dr Trott said.

“In the past, antibiotics were used to control these pathogens. However, the use of these agents is being phased out in many countries due to concerns over the transfer of antibiotic resistance to human pathogens.

“Alternative strategies to antibiotics must be investigated, and I hope that this basic research project may lead to new methods of control.

“For example, vaccines based on novel surface proteins found in the organisms could be an applied outcome of this research.”

He said if scientists could understand the way the organism attached itself to the surface of the intestine and how its proteins were involved in this process, there was a good opportunity for controlling it.

Dr Trott said B. pilosicoli also was a common organism in developing countries and among immuno-suppressed human patients. Its significance for causing disease in humans was receiving further recognition.

It led to failure to gain weight in grower pigs, while in poultry, birds with these organisms had sub-optimal feed conversion rates, increased numbers of weak chicks and produced fewer eggs.

Dr Trott, from Milton, said he “truly loved” working on the organism, which had a remarkable attachment mechanism, forming a covering like a shag pile carpet on the colon surface.

He characterised and named B. pilosicoli during his PhD studies with Professor David Hampson at Murdoch University in the late 1990s (“pilosicoli” literally means “of a hairy colon” in Latin).

B. pilosicoli is an evolutionary successful bacterial parasite,” he said.

“It out-competes other intestinal bacteria and establishes itself in a range of hosts, initiating damage to host cells without eliciting a strong inflammatory response.”

Dr Trott is also working with Professor Ben Adler of the ARC Centre of Excellence in Structural and Functional Microbial Genomics at Monash University in a project to sequence the entire genome of a related organism which causes a more serious condition, swine dysentery. This project will hopefully develop a vaccine against swine dysentery, which affects 10-15 percent of the Australian pig herd.

The University of Queensland’s outstanding research achievements are being celebrated during Research Week 2006 from September 18 to 22.

The event is designed to raise awareness of current UQ research among the university community, the general public, industry, government and the media.

For details of this year’s program visit http://www.uq.edu.au/research-week/

Media inquiries: Dr Darren Trott (07 3365 2985) or Jan King at UQ Communications (0413 601 248).