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
Cultivating numerically significant soil bacteria. The vast majority of soil bacteria have not been able to be studied in the laboratory because they cannot be grown outside the soil. They are therefore termed unculturable. Most of these belong to groups that are completely unstudied. Advances made in the Janssen lab have overcome this impediment to laboratory cultivation of numerically abundant and globally distributed soil bacteria. This project will develop these advances to generate simple a ....Cultivating numerically significant soil bacteria. The vast majority of soil bacteria have not been able to be studied in the laboratory because they cannot be grown outside the soil. They are therefore termed unculturable. Most of these belong to groups that are completely unstudied. Advances made in the Janssen lab have overcome this impediment to laboratory cultivation of numerically abundant and globally distributed soil bacteria. This project will develop these advances to generate simple and widely applicable methods to enable many of the previously unculturable soil bacteria to be studied. This will allow assessments of their ecological roles and biotechnological potentials to be made.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
Quantum Dot Nanocrystals: Smart Materials for Microbiology. Quantum dots were originally developed for computers but have many advantages over fluorescent dyes currently in use. They can be coupled to larger structures and a excitation with a laser allows simultaneous multiple analyses ("multiplexing"). We propose to adapt these structures for use in microbial ecology because this field is one of the least understood areas in biology. The technology we will develop will have far broader uses, a ....Quantum Dot Nanocrystals: Smart Materials for Microbiology. Quantum dots were originally developed for computers but have many advantages over fluorescent dyes currently in use. They can be coupled to larger structures and a excitation with a laser allows simultaneous multiple analyses ("multiplexing"). We propose to adapt these structures for use in microbial ecology because this field is one of the least understood areas in biology. The technology we will develop will have far broader uses, and will create new diagnostic tools for monitoring and understanding microbial ecosystems would be invaluable in a number of fields. Examples are medical diagnostics, waste-water treatment, bioremediation, food and agriculture, bioprotection and biodiscovery.Read moreRead less
Genome-level insight into the dynamics of a model coral microbiome. The aim of the project is to examine structural and functional microbiome dynamics in an ecologically important coral on the Great Barrier Reef along a natural temperature gradient. Microorganisms form an intimate symbiotic relationship with corals and are critical to their health. However, the microbiome can be disrupted by environmental perturbations, including higher-than-normal ocean temperatures, leaving the coral susceptib ....Genome-level insight into the dynamics of a model coral microbiome. The aim of the project is to examine structural and functional microbiome dynamics in an ecologically important coral on the Great Barrier Reef along a natural temperature gradient. Microorganisms form an intimate symbiotic relationship with corals and are critical to their health. However, the microbiome can be disrupted by environmental perturbations, including higher-than-normal ocean temperatures, leaving the coral susceptible to disease and bleaching. Currently, our understanding of how the microbiome composition and metabolic function change in response to seasonal temperature variation and disease is limited. This project is designed to provide insight into the role the microbiome plays in maintaining coral health and may aid in the long-term preservation of the reefs.Read moreRead less
Defining how bacteriophage shape the biofilm lifecycle of bacteria. Bacteriophages are viruses that infect bacteria and they represent a significant selective pressure that drives the evolution of bacteria. We will study the genetic mechanisms by which genes encoded by a bacteriophage can contribute to increased survival of bacteria in the environment.
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
A novel process for removing phosphorus microbiologically from wastewater. Australia is a water limited continent, and its rivers and lakes are priceless assets, but because of climatic conditions, these are especially sensitive to blooms of 'blue green algae'. Some are highly toxic, and water containing them is unsuitable for most purposes. Current technology for P removal requires constructing complex plant configurations, and most of these operate unpredictably and unreliably. This project ....A novel process for removing phosphorus microbiologically from wastewater. Australia is a water limited continent, and its rivers and lakes are priceless assets, but because of climatic conditions, these are especially sensitive to blooms of 'blue green algae'. Some are highly toxic, and water containing them is unsuitable for most purposes. Current technology for P removal requires constructing complex plant configurations, and most of these operate unpredictably and unreliably. This project will develop and fully evaluate a revolutionarily different alternative with a fully aerobic system, capable of being added onto the end of a conventional treatment plant, making protection of rivers and streams simpler and more feasible. Read moreRead less