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
A functional genomic approach for understanding metal ion adaptation in marine cyanobacteria. Unicellular marine cyanobacteria constitute 20-40% of total marine chlorophyll biomass and carbon fixation, and hence significantly impact the global carbon cycle and are very relevant to combating global warming. This research will reveal some of the major mechanisms by which marine cyanobacteria have adapted to metal levels in coastal and oligotrophic environments. Thus these results will help us und ....A functional genomic approach for understanding metal ion adaptation in marine cyanobacteria. Unicellular marine cyanobacteria constitute 20-40% of total marine chlorophyll biomass and carbon fixation, and hence significantly impact the global carbon cycle and are very relevant to combating global warming. This research will reveal some of the major mechanisms by which marine cyanobacteria have adapted to metal levels in coastal and oligotrophic environments. Thus these results will help us understand the distribution and diversity of these organisms in relation to global primary productivity. They will also lead to the development of more robust biomarkers for metal stress and pollution in coastal environments.Read moreRead less
Further Genetic and Molecular studies of an Important Prokaryotic Regulator Protein TyrR. Genomes encode many functions whose expression varies dramatically depending on particular cellular environments. Special proteins called Regulator Proteins act as sensors to detect subtle changes in the environment and, in response, to influence the expression of certain genes either dampening them down or stimulating their activity. We are working with the TyrR regulator protein of the simple bacterium E ....Further Genetic and Molecular studies of an Important Prokaryotic Regulator Protein TyrR. Genomes encode many functions whose expression varies dramatically depending on particular cellular environments. Special proteins called Regulator Proteins act as sensors to detect subtle changes in the environment and, in response, to influence the expression of certain genes either dampening them down or stimulating their activity. We are working with the TyrR regulator protein of the simple bacterium Escherichia coli to elucidate the molecular strategies used in these controls. Because this protein controls the expression of a number of genes with diverse functions, evolution has selected equally diverse mechanisms to achieve appropriate transcriptional responses. The detailed knowledge of the E.coli genome and of the various genes regulated by TyrR make it an excellent system for such fundamental studies.Read moreRead less
Cellular Gene Regulation Networks. The benefit to Australia will be scientific in terms of providing an understanding of how cells integrate transcriptional control systems and the networks that are involved. This will inform research on folate deficiency and aberrant human development and towards identifying genes that are important in improving efficiency of microbial fermentations. Additional and more practical major benefits will follow from the development of tools to analyse interaction ....Cellular Gene Regulation Networks. The benefit to Australia will be scientific in terms of providing an understanding of how cells integrate transcriptional control systems and the networks that are involved. This will inform research on folate deficiency and aberrant human development and towards identifying genes that are important in improving efficiency of microbial fermentations. Additional and more practical major benefits will follow from the development of tools to analyse interactions between control systems, including software of value to the research community. The work will provide postgraduate students with major training in up-to-date genomic technologies, and in the interface between application of bioinformatics and experimental science.
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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
The evolution of bacterial pathogenesis: a genomic approach. The outcome of this research will be a better understanding of the genes involved with adaptation to particular pathogenic lifestyles. Specifically, genes that are rapidly evolving in selected bacterial pathogens of medical and veterinary importance will be identified using a bioinformatics approach that exploits the existence of multiple closely-related genome sequences. Such genes encode potential new targets for therapeutic interv ....The evolution of bacterial pathogenesis: a genomic approach. The outcome of this research will be a better understanding of the genes involved with adaptation to particular pathogenic lifestyles. Specifically, genes that are rapidly evolving in selected bacterial pathogens of medical and veterinary importance will be identified using a bioinformatics approach that exploits the existence of multiple closely-related genome sequences. Such genes encode potential new targets for therapeutic intervention that provide alternatives in the face of emerging antibiotic resistance. Importantly, the methodology developed in this project is broadly applicable to the study of evolution of bacterial pathogenesis in any background: medical, agricultural or horticultural.Read moreRead less
Peril and promise: Origins and spread of integron gene cassettes. Integrons have a major role in spreading antibiotic resistance genes among pathogens. They do so by capturing gene cassettes encoding resistance, yet how these cassettes are generated, the taxa in which they originate, and the range of traits that cassettes can encode have been outstanding questions for 30 years. This project addresses these long standing questions. The project will analyze single bacterial cells to detect newly ....Peril and promise: Origins and spread of integron gene cassettes. Integrons have a major role in spreading antibiotic resistance genes among pathogens. They do so by capturing gene cassettes encoding resistance, yet how these cassettes are generated, the taxa in which they originate, and the range of traits that cassettes can encode have been outstanding questions for 30 years. This project addresses these long standing questions. The project will analyze single bacterial cells to detect newly generated cassettes and assign them to specific taxa, using an innovative method that links cassette DNA to bacterial 16S rDNA. Understanding cassette origins is the key to controlling their activity, both to harness integrons for biotechnology, and to prevent pathogens from acquiring new, dangerous traits. 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 development of a two-colour flow cytometric assay for the detection of whole cell biosensors in environmental samples. Macquarie University and the University of Copenhagen have expertise in fluorescence detection and whole cell biosensors respectively. The project will take advantage of these skills and develop a sensitive assay for monitoring biosensor bacteria in soil. The technology will be significant as it will enable real time analysis of antibiotic production in situ through the de ....The development of a two-colour flow cytometric assay for the detection of whole cell biosensors in environmental samples. Macquarie University and the University of Copenhagen have expertise in fluorescence detection and whole cell biosensors respectively. The project will take advantage of these skills and develop a sensitive assay for monitoring biosensor bacteria in soil. The technology will be significant as it will enable real time analysis of antibiotic production in situ through the detection of GFP expression. This work will then be used to isolate new antibiotic produces and will be extended to research into the bioavailability of toxic compounds and stress. An existing collaboration between the two institutions will be extended enabling the transfer and application of biosensor technology to Australia.Read moreRead less
Defining New Building Blocks for the Construction of Artificial Genetic Circuits. By characterising the components of a natural genetic switch, we will make available a set of well defined genetic building blocks for construction of rationally designed biological circuits. The ability to build such circuits would have significant economic benefit in areas such as metabolic engineering, to improve the efficiency of production of natural compounds from micro-organisms, and in biomedicine, for the ....Defining New Building Blocks for the Construction of Artificial Genetic Circuits. By characterising the components of a natural genetic switch, we will make available a set of well defined genetic building blocks for construction of rationally designed biological circuits. The ability to build such circuits would have significant economic benefit in areas such as metabolic engineering, to improve the efficiency of production of natural compounds from micro-organisms, and in biomedicine, for the controlled release of therapeutic compounds. The involvement of Honours and Ph.D students in this project will expose the next generation of Australian scientists to this emerging discipline. International collaboration leading to publications in high impact scientific journals will enhance Australia's scientific reputation.Read moreRead less