Evolution of diverse symbiotic phenotypes among native soil bacteria following spread of a genomic island from a rhizobial inoculant. The quality of legume protein depends on symbiotic nitrogen fixation by root nodule bacteria (RNB). Sustainable legume production in Australian agriculture depends on legume inoculation with effective strains of these bacteria. Unfortunately inoculant strains transfer DNA to other soil bacteria resulting in soil populations of RNB that compete for nodulation but a ....Evolution of diverse symbiotic phenotypes among native soil bacteria following spread of a genomic island from a rhizobial inoculant. The quality of legume protein depends on symbiotic nitrogen fixation by root nodule bacteria (RNB). Sustainable legume production in Australian agriculture depends on legume inoculation with effective strains of these bacteria. Unfortunately inoculant strains transfer DNA to other soil bacteria resulting in soil populations of RNB that compete for nodulation but are less effective in nitrogen fixation. This transfer of DNA threatens a $2 billion asset in Australian agriculture. We will use molecular microbial ecology to investigate the mechanisms of genetic transfer of symbiotic DNA in RNB, and use this knowledge to prevent it.Read moreRead less
Bacterial Proteomics: From Cell Division to Novel Antibiotic Targets. When a cell divides it is essential that each newborn cell gets a complete copy of the DNA. To ensure that this happens, cell division must be tightly controlled. It is not known how this occurs in bacteria. However, if we knew what molecules were involved in this control, we could target them to kill harmful bacteria. This project aims to identify such regulatory molecules as candidate targets for antimicrobial agents, with a ....Bacterial Proteomics: From Cell Division to Novel Antibiotic Targets. When a cell divides it is essential that each newborn cell gets a complete copy of the DNA. To ensure that this happens, cell division must be tightly controlled. It is not known how this occurs in bacteria. However, if we knew what molecules were involved in this control, we could target them to kill harmful bacteria. This project aims to identify such regulatory molecules as candidate targets for antimicrobial agents, with a view to developing powerful, novel antibiotics to protect us from the imminent threat of bioterrorism and antibiotic-resistant bacteria.
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Unlocking the potential of bacterial polymers by defining key determinants. Sugary structures that coat the surface of some bacteria, known as capsules, can be modified by bacterial viruses (bacteriophage) in the environment. For the bacterial genus Acinetobacter, this influences their use as naturally renewable 'green' biopolymers for remediating environments contaminated with petroleum hydrocarbons. This project aims to characterise crucial capsule polymerase enzymes using a combination of bio ....Unlocking the potential of bacterial polymers by defining key determinants. Sugary structures that coat the surface of some bacteria, known as capsules, can be modified by bacterial viruses (bacteriophage) in the environment. For the bacterial genus Acinetobacter, this influences their use as naturally renewable 'green' biopolymers for remediating environments contaminated with petroleum hydrocarbons. This project aims to characterise crucial capsule polymerase enzymes using a combination of bioinformatics and experimental methodologies to establish how bacteriophage influence Acinetobacter capsules. Outcomes include the development of an innovative genomics pipeline to detect capsule change, improving the use of living bacteria for bioremediation and sustainable rehabilitation of natural ecosystems.Read moreRead less
Discovery Early Career Researcher Award - Grant ID: DE240100316
Funder
Australian Research Council
Funding Amount
$435,431.00
Summary
Population genomic methods for modelling bacterial pathogen evolution. This project aims to develop novel techniques to model bacterial genome evolution and improve our understanding of how major agricultural and human pathogens, including Enterococcus, Salmonella and E. coli, evolve. The project expects to generate new knowledge about how horizontal gene transfer shapes the evolution of bacteria and how these dynamics vary over different temporal scales. Expected outcomes include methodological ....Population genomic methods for modelling bacterial pathogen evolution. This project aims to develop novel techniques to model bacterial genome evolution and improve our understanding of how major agricultural and human pathogens, including Enterococcus, Salmonella and E. coli, evolve. The project expects to generate new knowledge about how horizontal gene transfer shapes the evolution of bacteria and how these dynamics vary over different temporal scales. Expected outcomes include methodological advances that will enable the analysis of massive contemporary datasets. These methods and resulting analyses will provide significant benefits including informing the design of superior long-term interventions to reduce bacterial disease in both agriculture and health that are robust to the evolution of bacteria.Read moreRead less
The role of dysregulated signalling by TORC1 in mitochondrial disease. The mitochondria are tiny subcellular compartments responsible for producing over 90 per cent of the cell's energy. Mitochondrial defects feature both in genetic diseases that directly affect the mitochondria and in most neurodegenerative diseases. These incurable diseases are expected to eclipse cancer as the second major cause of death worldwide by 2040. Using a simple model organism, Dictyostelium, previous research showed ....The role of dysregulated signalling by TORC1 in mitochondrial disease. The mitochondria are tiny subcellular compartments responsible for producing over 90 per cent of the cell's energy. Mitochondrial defects feature both in genetic diseases that directly affect the mitochondria and in most neurodegenerative diseases. These incurable diseases are expected to eclipse cancer as the second major cause of death worldwide by 2040. Using a simple model organism, Dictyostelium, previous research showed that dysregulated intracellular signalling by a cellular energy-sensing alarm protein is responsible for diverse cellular pathologies in mitochondrially diseased cells. This project will determine the role in these pathways of a second cellular stress-sensing protein complex, TORC1. New treatment possibilities may emerge.Read moreRead less
Safety in numbers: Bacterial aggregation and adaptation to oxidative stress. This project is a new collaboration which links two molecular microbiologists with the complementary skills required to make new insights into the molecular processes that underpin bacterial aggregation and biofilm formation. Biofilms are of immense significance in medical, industrial and environmental settings and so the fundamental information gained from this project will have wider relevance to the field of microbio ....Safety in numbers: Bacterial aggregation and adaptation to oxidative stress. This project is a new collaboration which links two molecular microbiologists with the complementary skills required to make new insights into the molecular processes that underpin bacterial aggregation and biofilm formation. Biofilms are of immense significance in medical, industrial and environmental settings and so the fundamental information gained from this project will have wider relevance to the field of microbiology. An outcome of this proposal will be fundamental knowledge about the production of surface adhesins that will form the basis for rational treatment of disease in the future. Prevention of aggregation and biofilm formation would make bacterial populations more susceptible to conventional antibiotic treatment.Read moreRead less
Molecular mechanisms of pilin glycosylation in Neisseria: a model system for protein glycosylation in bacteria. The disease causing bacteria Neisseria meningitidis and Neisseria gonorrhoeae are important human pathogens. Cell surface structures, called pili, are known to be important in allowing the bacteria to stick to host cells. Genetic and structural studies have identified that the protein subunits, which make up pili, are glycosylated - modified by the addition of sugars. Until recently ....Molecular mechanisms of pilin glycosylation in Neisseria: a model system for protein glycosylation in bacteria. The disease causing bacteria Neisseria meningitidis and Neisseria gonorrhoeae are important human pathogens. Cell surface structures, called pili, are known to be important in allowing the bacteria to stick to host cells. Genetic and structural studies have identified that the protein subunits, which make up pili, are glycosylated - modified by the addition of sugars. Until recently glycosylation of Gram-negative bacterial proteins was not thought to occur, however our recent work with these bacteria, and other groups studying Pseudomonas and Campylobacter, have shown that this process may be widespread. In our previous studies, we have identified and analysed a number of genes involved in pili glycosylation, in bacteria, which make known sugar structures. We have used this information to developed models for how the biochemistry and physiology of the glycosylation system may work. With a well-established structure and many genes already identified, glycosylation in Neisseria represents the best available model system to study this novel and important process. In the proposed study we describe experiments planned to test our models and reveal the molecular detail of this process. This study could lead to major advances in our understanding of this process and, when understood, may have future applications in biotechnology.Read moreRead less
The host specificity of bacterial pathogens. The vast majority of microorganisms that cause diseases in animals are host specific. In other words, they cause disease exclusively in a particular animal species, but are harmless for others. Despite considerable recent advances in our understanding of the mechanisms used by microorganisms in general to cause disease, in most cases the underlying basis of host-specificity is not known. In this project, we will use two animal pathogens, rabbit-spe ....The host specificity of bacterial pathogens. The vast majority of microorganisms that cause diseases in animals are host specific. In other words, they cause disease exclusively in a particular animal species, but are harmless for others. Despite considerable recent advances in our understanding of the mechanisms used by microorganisms in general to cause disease, in most cases the underlying basis of host-specificity is not known. In this project, we will use two animal pathogens, rabbit-specific enteropathogenic E. coli and the closely related bacterium, Citrobacter rodentium, which specifically infect rabbits and mice respectively, to investigate the molecular basis of host specificity.Read moreRead less
The biology of integrons and their role in bacterial adaptation. Bacteria evolve in ways that animals and plants do not. One of the tools available is the ability to share genes amongst individuals in a community. One example of this is the very rapid spread of antibiotic resistance genes in pathogens. Here we will be studying a genetic element that greatly contributes to this horizontal spread of genes. This will lead to a better understanding of how bacteria work, the direct benefits of whic ....The biology of integrons and their role in bacterial adaptation. Bacteria evolve in ways that animals and plants do not. One of the tools available is the ability to share genes amongst individuals in a community. One example of this is the very rapid spread of antibiotic resistance genes in pathogens. Here we will be studying a genetic element that greatly contributes to this horizontal spread of genes. This will lead to a better understanding of how bacteria work, the direct benefits of which includes the discovery of new pathways and genes for the biotechnology industry and greater understanding of how bacteria cause disease in us, other animals and in commercial crops.Read moreRead less
How does Clostridium perfringens carry multiple closely related plasmids? The project aims to determine how bacteria are able to replicate and maintain multiple copies of very closely related extrachromosomal elements or plasmids in the same cell. These plasmids are important as they encode toxin genes and antibiotic resistance genes. The project proposes to examine two fundamental hypotheses that are postulated to explain this novel phenomenon. The anticipated outcome of the project is the adva ....How does Clostridium perfringens carry multiple closely related plasmids? The project aims to determine how bacteria are able to replicate and maintain multiple copies of very closely related extrachromosomal elements or plasmids in the same cell. These plasmids are important as they encode toxin genes and antibiotic resistance genes. The project proposes to examine two fundamental hypotheses that are postulated to explain this novel phenomenon. The anticipated outcome of the project is the advancement of fundamental knowledge of how bacteria that cause disease in food-production animals can maintain the genetic elements that enable them to cause these diseases. This would contribute to our understanding of the epidemiology of these economically significant animal pathogens and may support the development of new methods of prevention or treatment.Read moreRead less