Some of the world's most important diseases, including important diseases of indigenous chilren and the hospitalised elderly are caused by bacteria that carry a surface coating called a capsule. It is not clear how this capsule is retained by bacteria. Resolution of this question could lead to the development of new disinfectants that will stop hospital-acquired infections, to new reagents that can be incoporated into medical devices where bacteria frequently grow, and new antibiotics.
This program will investigate the strategies used by pathogenic bacteria to cause human diseases. The research will focus on how bacteria initiate infections, how they invade, cause cell and tissue damage and respond to their human host. It will also examine how the host’s innate immune system interacts with these bacteria. The results will provide new insights into host-pathogen interactions and reveal new targets for the development of novel antibacterial drugs and vaccines.
The Molecular Basis Of Bacterial Infectious Diseases
Funder
National Health and Medical Research Council
Funding Amount
$16,230,996.00
Summary
Bacterial infectious diseases are a serious threat to human health, accounting for over 10 million deaths each year. This multidisciplinary collaborative team is investigating the complex interactions between major disease-causing bacteria and their human hosts, in order to determine how they cause disease. These studies will make a major contribution to fundamental knowledge in this field. This information is also essential for the development of cheaper and more effective vaccines, as well as ....Bacterial infectious diseases are a serious threat to human health, accounting for over 10 million deaths each year. This multidisciplinary collaborative team is investigating the complex interactions between major disease-causing bacteria and their human hosts, in order to determine how they cause disease. These studies will make a major contribution to fundamental knowledge in this field. This information is also essential for the development of cheaper and more effective vaccines, as well as novel drugs. These are urgently needed to reduce death and illness due to bacterial infectious diseases in the 21st century. 11Read moreRead less
The Development Of Novel, Biofilm-resistant Biomaterials
Funder
National Health and Medical Research Council
Funding Amount
$147,360.00
Summary
Almost all patients who are catheterised long term develop a bacterial infection. Most often, the infection is the result of colonisation of the catheter surface by bacteria. Bacterial colonisation of the surface of biomedical devices represents a significant health threat as such bacterial biofilms are extremely resistant to traditional antibiotic regimens. This project aims to develop novel materials that prevent bacterial colonisation on catheters and other biomedical related devices. Our tec ....Almost all patients who are catheterised long term develop a bacterial infection. Most often, the infection is the result of colonisation of the catheter surface by bacteria. Bacterial colonisation of the surface of biomedical devices represents a significant health threat as such bacterial biofilms are extremely resistant to traditional antibiotic regimens. This project aims to develop novel materials that prevent bacterial colonisation on catheters and other biomedical related devices. Our technology is based on compounds identified from a marine alga that prevent bacterial colonisation of its surface. Similarly, we have shown that these compounds, when coated onto test surfaces, prevent bacterial colonisation of a range of materials.Read moreRead less
Characterisation Of A Novel Type Of Promoter Controlling Expression Of Virulence Genes In Neisseria.
Funder
National Health and Medical Research Council
Funding Amount
$200,880.00
Summary
This project will investigate how two different types of bacteria control genes that are involved in determining their disease-causing ability. The expression of many bacterial genes is controlled by a sophisticated battery of regulatory systems that respond to individual, very specific, environmental signals. Such regulatory systems are capable of exerting very precise control over the level of gene expression, in response to the concentration of specific molecules in the immediate environment. ....This project will investigate how two different types of bacteria control genes that are involved in determining their disease-causing ability. The expression of many bacterial genes is controlled by a sophisticated battery of regulatory systems that respond to individual, very specific, environmental signals. Such regulatory systems are capable of exerting very precise control over the level of gene expression, in response to the concentration of specific molecules in the immediate environment. However, there is evidence to suggest that many important disease-causing bacteria are much less reliant on specific regulatory systems. Instead, these bacteria rely more heavily what have been termed global systems for the regulation of gene expression. Such systems typically respond to less specific signals, such as the growth rate of the bacterial cell, but nevertheless appear capable of very precise control. We have evidence for a previously uncharacterised type of global control system that appears to be widespread amongst bacteria. It is likely that many virulence genes in a variety of disease-causing bacteria will prove to be controlled by similar means. Therefore this project will not only provide an insight into how expression of these particular virulence determinants is regulated, but will yield data that may help in our understanding of precise global regulatory processes in other bacterial species of medical importance.Read moreRead less
Origins And Relationships Of Shigella And Enteroinvasive Escherichia Coli
Funder
National Health and Medical Research Council
Funding Amount
$377,310.00
Summary
Shigella is a well known highly infectious human pathogen with as few as 10 cells allowing effective spread by infected food or water, and also by person to person contact. Shigellosis is a particularly significant disease for children due to lack of pre-existing immunity and greater chance of transfer by fecal-oral route. One group of E. coli called Enteroinvasive E. coli (EIEC) resembles Shigella in many aspects from disease symptoms to biochemical properties. EIEC is a major cause of diarrhoe ....Shigella is a well known highly infectious human pathogen with as few as 10 cells allowing effective spread by infected food or water, and also by person to person contact. Shigellosis is a particularly significant disease for children due to lack of pre-existing immunity and greater chance of transfer by fecal-oral route. One group of E. coli called Enteroinvasive E. coli (EIEC) resembles Shigella in many aspects from disease symptoms to biochemical properties. EIEC is a major cause of diarrhoea in less developed countries and has also caused large outbreaks in developed countries. It is now clear that Shigella and E. coli are really one species. EIEC and Shigella strains are variants of E. coli with humans as the only host. However separation of the two in all records and most studies means that there is no integrated understanding of the forms. We aim to study the relationships of Shigella and EIEC and expect significant insights into the origins of Shigella-EIEC. This will facilitate diagnosis and understanding of the disease(s) and lead to a far better classification . EIEC-Shigella strains have arisen from other E. coli independently. This has happened seven times in the derivation of Shigella and we expect more such events with EIEC. An interesting phenomenon during this process is that strains tend to lose metabolic functions. In this study we will look at what, why and how functions are lost. O antigens are important in evading the host immune system. Shigella strains obtained many O antigens, the majority apparently from other species. This is quite likely the key to its success. We will look at how Shigella obtained new O antigens. This project will be significant in the understanding of Shigell-EIEC, a very significant human pathogen, and in general for understanding emergence of new pathogens.Read moreRead less
Investigation Of The Role Of Specific Mucous Associated Bacteria In Children And Young Adults With Crohns Disease
Funder
National Health and Medical Research Council
Funding Amount
$431,764.00
Summary
The role of bacteria in Crohn's disease is well accepted however to date no conclusive agents have been identified. Recent animal studies have implicated mucus-associated bacteria. We have recently shown that such bacteria, the Helicobacteriaceae, are present in humans and children with Crohn's disease. The aim of this project is to determine in children and young adults the role of these bacteria in IBD thus providing information that could be used to design improved therapies for IBD.
Investigation Of The Effects Of Polymicrobial Infection On The Induction Of Otitis Media
Funder
National Health and Medical Research Council
Funding Amount
$235,511.00
Summary
Middle ear infection is a highly prevalent paediatric disease characterised by an inflammation of the middle ear and is the most prevalent illness of childhood. It is reported that greater than 80% of children have had at least one episode of acute otitis media by 3 years of age and almost 40% of children have more than 6 episodes by age 7 years. The cause and pathogenesis of middle ear infection are multifactorial and influence of prevalence and chonicity of the infections. Prevention of bacter ....Middle ear infection is a highly prevalent paediatric disease characterised by an inflammation of the middle ear and is the most prevalent illness of childhood. It is reported that greater than 80% of children have had at least one episode of acute otitis media by 3 years of age and almost 40% of children have more than 6 episodes by age 7 years. The cause and pathogenesis of middle ear infection are multifactorial and influence of prevalence and chonicity of the infections. Prevention of bacterial middle ear infection caused by Streptococcus pneumoniae, nontypeable Haemophilus influenzae and Moraxella catarrhalis requires a much better knowledge of how these bacteria interact with each other and with the host. The poor efficacy of the current pneumococcal paediatric vaccine for preventing middle ear infections highlights this deficiency in our knowledge and will impede the development of a suitable multvalent vaccine to prevent infection by the 3 major bacterial pathogens. This study will investigate how the bacteria colonising the respiratory tract interact during infection and how they affect the host.Read moreRead less
Crohn's disease is a severe, chronic inflammatory disease of the gut which affects up to 50,000 Australians. The majority of patients develop the disease in their twenties, with significant impact on their quality of life. Our preliminary work has identified a novel gene, which could potentially cause a critical reduction in the production of anti-bacterial proteins by cells in the small bowel. Exploring the function of this gene in relation to clinical outcome could lead to better treatment.