Characterization Of A Novel Secretion System Necessary For Porphyromonas Gingivalis Virulence.
Funder
National Health and Medical Research Council
Funding Amount
$596,412.00
Summary
In this study we will characterize a novel bacterial secretion system that we have discovered. This sytem mediates the secretion of proteins from the bacterial cell and their attachment to the cell surface. This system is essential for the virulence of Porphyromonas gingivalis, a bacterium associated with chronic periodontitis. The chacterization of this system may offer opportunities for the development of new treatments to target this disease.
Characterization Of The Type IX Secretion System In Porphyromonas Gingivalis
Funder
National Health and Medical Research Council
Funding Amount
$831,656.00
Summary
Periodontitis is associated with the keystone pathogen Porphyromonas gingivalis. We have identified a novel protein secretion machine comprised of at least 12 components in P. gingivalis which transports the bacterium's major virulence factors to the cell surface and attaches them to the outer membrane. We aim to determine the spatial arrangement and specific role of each of these 12 components and thereby provide targets for future treatments against this disease.
Dissecting Retrograde Endosome- To-Golgi Transport Pathways Relevant To Development, Cell Function And Disease
Funder
National Health and Medical Research Council
Funding Amount
$545,216.00
Summary
Movement of molecules within cells by a process known as membrane transport is critical for normal cell function and also exploited by bacteria to promote infection. The pathway that connects the import pathway to the export pathway is essential for the function of a large number of proteins, however this connecting pathway is poorly characterised. This study will define the machinery of this trafficking pathway, which will provide the ability to modulate biological processes and cytotoxicity.
Macrophages are important cells at the front-line of immunity where one of their main roles is to release anti-bacterial proteins. We will study the macrophage molecules, subcellular organelles and pathways that help to release these proteins to kill bacteria and fight infection. Our studies will identify new cellular targets for boosting immunity and treating inherited diseases with defective macrophage function.
Characterisation Of A Newly-discovered, Virulence-associated, Protein Secretion System Of Enteropathogenic E. Coli
Funder
National Health and Medical Research Council
Funding Amount
$582,149.00
Summary
The cell walls of bacteria act as a barrier to the export of any proteins they produce. We recently discovered a protein secretion system, which diarrhoea-causing strains of E. coli require to cause disease. The aim of this study is to characterise this secretory system, and discover how it functions and what it secretes. The knowledge obtained from this research will shed new light on how E. coli causes disease and could reveal novel methods to treat and prevent infections with this bacterium.
Role Of Microbiota In The Developing Enteric Nervous System
Funder
National Health and Medical Research Council
Funding Amount
$661,979.00
Summary
The correct development of neurons in the gut is vital for digestive functions. This project will provide novel insights into how environmental factors such as the bacteria that reside in the gut and changes in diet affect maturation of the gut’s nervous system. The data will improve knowledge of the effects of widely used antibiotics and probiotics, which will facilitate strategies to improve human health and quality of life.
Intracellular Survival Of Burkholderia Pseudomallei And Evasion Of Autophagy
Funder
National Health and Medical Research Council
Funding Amount
$450,799.00
Summary
Melioidosis is a disease with high mortality that is caused by the bacterium Burkholderia pseudomallei. Autophagy is a natural part of the mammalian immune system. This project seeks to explain how Burkholderia pseudomallei avoids killing by host autophagy and identify the bacterial factors necessary for its survival within cells. The identified genes will be future targets for medical intervention.
Neural Mechanisms Mediating Hypersecretion And Motility Patterns Induced By Enterotoxins
Funder
National Health and Medical Research Council
Funding Amount
$415,250.00
Summary
This project aims to identify the nerve cells that are responsible for the massive oversecretion of water and salt seen with cholera and other diseases producing diarrhoea. Many of these disease act through specific toxins and, although the biochemical targets of these toxins are reasonably well understood, the nerve cells on which they act have never been identified. Furthermore, the mechanisms that couple the oversecretion with a massive increase in the propulsive activity of the intestine are ....This project aims to identify the nerve cells that are responsible for the massive oversecretion of water and salt seen with cholera and other diseases producing diarrhoea. Many of these disease act through specific toxins and, although the biochemical targets of these toxins are reasonably well understood, the nerve cells on which they act have never been identified. Furthermore, the mechanisms that couple the oversecretion with a massive increase in the propulsive activity of the intestine are also unknown. We will investigate each of these questions using the small intestine of the guinea-pig, because the nerve circuit in this preparation is better understood than that of any other. Nerve cells that respond to three specific toxins, each known to activate the nervous system via different mechanisms, will be determined using intracellular recording methods, injection of marker dyes and methods that allow the identification of their neurochemistry. This will allow the functions of responsive nerve cells to be identified and their places in the circuits that control secretion and propulsion to be determined. This information will be correlated with studies in whole animals being undertaken in Sweden so that potential sites for intervention can be identified.Read moreRead less
Expression And Secretion Of Large Clostridial Toxins From The Pathogenic Clostridia.
Funder
National Health and Medical Research Council
Funding Amount
$332,258.00
Summary
The large clostridial toxins are an important family of bacterial virulence factors that includes toxins from many disease-causing clostridial species. Despite their impact on public health, pathogenesis of disease caused by these bacteria is poorly understood. We will analyse how these bacteria regulate the production and secretion of the large toxins, which will give us a better understanding of the mechanisms of disease causation as well as identifying novel common therapeutic targets.
Secretion is an essential step in memory and learning, control of metabolism and reproduction and the functioning of most organs. Secretory dysfunction also underlies many diseases including type 2 diabetes. We plan experiments to test for a new model of control of insulin secretion.