Functional Biology Of Large Serine Recombinases From Mobile Antibiotic Resistance Elements
Funder
National Health and Medical Research Council
Funding Amount
$436,328.00
Summary
In recent years there has been increasing concern about the emergence of multiply antibiotic resistant strains of many common bacterial pathogens. The development of multiple resistance phenotypes has already led to compromises in the ability to successfully treat infected patients and to increased treatment costs. The emergence of these resistant bacteria is the result of excessive or inappropriate use of antibiotics and the ability of antibiotic resistance genes to be transferred from resistan ....In recent years there has been increasing concern about the emergence of multiply antibiotic resistant strains of many common bacterial pathogens. The development of multiple resistance phenotypes has already led to compromises in the ability to successfully treat infected patients and to increased treatment costs. The emergence of these resistant bacteria is the result of excessive or inappropriate use of antibiotics and the ability of antibiotic resistance genes to be transferred from resistant to susceptible bacteria, either within or between bacterial species. The movement of resistance elements that are integrated into the bacterial genome often involves their excision from their existing site and their subsequent integration into another site in the same or a different genome. This project centres on the analysis of this process in resistant bacteria that cause major disease problems in our hospitals. The research project will focus on MRSA (Multiply Resistant Staphylococcus aureus) which has been a serious problem in our hospitals for many years, and Clostridium difficile, an emerging pathogen of increasing importance and which causes a very serious and chronic form of colitis in hospital patients. By studying the biochemical processes by which enzymes called recombinases excise and subsequently integrate antibiotic resistance elements from these bacteria and by determining the three dimensional structure of such enzymes we aim to determine the mechanism of action of members of this important enzyme family. The major outcomes of the project will be an increased understanding of one of the major processes by which antibiotic resistance determinants can spread both within and between bacterial pathogens of importance in the hospital environment. These studies will contribute towards the development of improved methods for controlling the spread of resistant pathogens and resistance genes in the hospital environment, with concomitant benefits to human health.Read moreRead less
Structural Studies Of Bacterial Pore-forming Protein Toxins
Funder
National Health and Medical Research Council
Funding Amount
$509,017.00
Summary
In this project the three-dimensional structures of proteins that form pores in membrane cell walls will be determined. These proteins are bacterial toxins and knowledge of their structure may prove useful in the design of new antibiotics. This project will focus on a class of toxins called the cholesterol-dependent cytolysins which are released by Gram positive bacteria such as Clostridia and Streptococcus and which cause a variety of nasty infectious diseases such as gas gangrene, pneumonia an ....In this project the three-dimensional structures of proteins that form pores in membrane cell walls will be determined. These proteins are bacterial toxins and knowledge of their structure may prove useful in the design of new antibiotics. This project will focus on a class of toxins called the cholesterol-dependent cytolysins which are released by Gram positive bacteria such as Clostridia and Streptococcus and which cause a variety of nasty infectious diseases such as gas gangrene, pneumonia and meningitis. The three-dimensional structures will be elucidated using X-ray crystallography. Protein crystallography is the study of three-dimensional shapes of proteins at near atomic resolution. In this method proteins are made to form crystals. X-ray beams are then shone on the crystals causing the X-rays to scatter in a pattern which is characteristic of the protein's three-dimensional shape. Knowledge of the structure of proteins is necessary for the complete understanding of their biological activity and is also very useful for the rational design of new drugs that may alter their activity.Read moreRead less
Evolution Of Pertussis Epidemics And Effect Of Genotypes On Infection Outcomes And Immunisation
Funder
National Health and Medical Research Council
Funding Amount
$657,781.00
Summary
Pertussis, or whooping cough, is caused by Bordetella pertussis. Despite high vaccine coverage, the incidence of pertussis has increased substantially in recent years in Australia. One of the contributing factors is changes in the pertussis strains. This project will determine the genetic composition and virulence characteristics of epidemic strains in Australia and investigate the effect of these strains on disease severity and vulnerability of vaccinated individuals to infection.
The biology, structure and function of bacterial virulence effectors. This project is closely aligned with the National Research Priority of Promoting and Maintaining Good Health and will establish a research framework to investigate novel virulence processes that allow bacterial pathogens to infect humans and cause disease. This fresh approach to the study of bacterial pathogenesis will sit outside classic genetic methods to investigate infection and immunity which rely heavily on genetic manip ....The biology, structure and function of bacterial virulence effectors. This project is closely aligned with the National Research Priority of Promoting and Maintaining Good Health and will establish a research framework to investigate novel virulence processes that allow bacterial pathogens to infect humans and cause disease. This fresh approach to the study of bacterial pathogenesis will sit outside classic genetic methods to investigate infection and immunity which rely heavily on genetic manipulation of the pathogen. Other than providing fundamental information on host-pathogen interactions, this work may lead to novel disease interventions by inhibition of bacterial virulence factor activity and/or enhancement of host inflammatory and immune responses.Read moreRead less
Nasal Epithelium As A Portal Of Entry For Burkholderia Pseudomallei, With Special Reference To Neurological Melioidosis
Funder
National Health and Medical Research Council
Funding Amount
$536,419.00
Summary
Melioidosis is a potentially fatal disease of manly tropical Australia and SE Asia and an emerging disease worldwide. It disproportionately affects indigenous Australians. It is caused by a bacterium found in soil and water and infection may be by inhalation in the rainy season. One manifestation of melioidosis is neurological symptoms. This project seeks to establish sites and pathways of infection resulting from inhalation, including the pathway from nasal mucosa to brain.
Functional characterisation of poly-histidine triad proteins. This project aims to understand the role and function of a novel family of surface proteins produced by Streptococci. These so-called polyhistidine triad proteins are known to contribute to capacity to cause disease in animals and humans, but we need to know how they work, as they may be excellent targets for novel drugs or vaccines.
Novel perspectives on the function of AB5 toxin B subunits in pathogenic bacterial. AB5 toxins are produced by bacteria that cause important diseases in humans and livestock. This project tests the hypothesis that the components of the toxins responsible for binding to host cells and tissues also directly contribute to cellular damage, thereby providing a better understanding of how AB5 toxin-producing bacteria cause disease.
How bacteria cause disease in the urinary tract. This project will investigate the virulence properties of uropathogenic Escherichia coli, the major causative agent of urinary tract infections (UTI) in humans. The results will help to understand how these bacterial pathogens cause disease and will impact strategies aimed at the prevention and treatment of chronic and recurrent UTI.
A One Health Approach To Assessing The Threat Of Clostridium Difficile To Australia’s Biosecurity: A Genomic Investigation Of Human, Animal And Environmental Isolates
Funder
National Health and Medical Research Council
Funding Amount
$318,768.00
Summary
Clostridium difficile is a bacterium that causes life-threatening diarrhoea in humans and animals and is a major public health issue in Australia. This project will study the genetic make-up of the bacterium and identify factors contributing to the emergence, evolution, and spread of C. difficile. This knowledge will be essential in guiding effective public health interventions and reducing deaths from C. difficile infection in humans and animals.
Role Of The Host Fibrinolytic System In Invasive Group A Streptococcal Disease
Funder
National Health and Medical Research Council
Funding Amount
$531,444.00
Summary
The flesh-eating bacterium group A streptococcus (GAS) is estimated to cause 700 million cases of self-limiting disease, and 600,000 cases of serious invasive disease each year. Approximately 25% of invasive infections are fatal. We have shown that GAS are able to hijack the host fibrinolytoc system to cause severe invasive infections. We plan to further examine the details of how this contributes to GAS disease. This research may contribute to the future devlopment of new therapeutics.