Environmental influence on evolutionary processes in bacterial populations. Bacterial populations exhibit remarkable adaptive capabilities in many environmental and medical settings. They respond to environmental stress in terms of altered gene expression, but what are the effects on mutation rates and fitness when cells grow at suboptimal growth rates? We plan to test whether the physiological state of an ancestral population is a determinant of a population's subsequent response to selection. ....Environmental influence on evolutionary processes in bacterial populations. Bacterial populations exhibit remarkable adaptive capabilities in many environmental and medical settings. They respond to environmental stress in terms of altered gene expression, but what are the effects on mutation rates and fitness when cells grow at suboptimal growth rates? We plan to test whether the physiological state of an ancestral population is a determinant of a population's subsequent response to selection. A simple model system using controlled culture conditions will be used to investigate the linkage between environment, mutation rate and fitness under selection. Demonstration of these linkages will have significant impacts on microbiology and understanding evolution.Read moreRead less
Genetics and evolution of Shigella O antigens. We use genome scale sequencing techniques to sequence 26 O-antigen gene clusters from Shigella. With the seven already known, this will give sequences for every O-antigen of Shigella. This will be the first time that such set is fully sequenced. Shigella are human specific pathogens, have emerged with the evolution of humans. O-antigens are important for their life and pathogenicity. This project will greatly extend our knowledge of the genetic basi ....Genetics and evolution of Shigella O antigens. We use genome scale sequencing techniques to sequence 26 O-antigen gene clusters from Shigella. With the seven already known, this will give sequences for every O-antigen of Shigella. This will be the first time that such set is fully sequenced. Shigella are human specific pathogens, have emerged with the evolution of humans. O-antigens are important for their life and pathogenicity. This project will greatly extend our knowledge of the genetic basis and evolution of this important polymorphism. O-antigens are used for typing Shigella and also elicit strong immunity. The molecular data will help establish DNA based typing and vaccine development.Read moreRead less
Evolution and mechanisms of interactions in biofilm communities. This project aims to study the long-term experimental evolution of a mixed species bacterial biofilm community. This project expects to gain understanding of the genetic and physiological basis of community evolution. Expected outcomes of this project will be an understanding of how synthetic communities evolve. This will significantly benefit the use of synthetic communities relevant to fields such as antibiotic design, biotechnol ....Evolution and mechanisms of interactions in biofilm communities. This project aims to study the long-term experimental evolution of a mixed species bacterial biofilm community. This project expects to gain understanding of the genetic and physiological basis of community evolution. Expected outcomes of this project will be an understanding of how synthetic communities evolve. This will significantly benefit the use of synthetic communities relevant to fields such as antibiotic design, biotechnology, bioremediation, and synthetic biology where evolution can be inhibited or exploited, respectively.Read moreRead less
Molecular Cell Biology and Comparative Genomics Of Planctomycetes and Verrucomicrobia In Relation To Evolution Of Cytoskeletal Proteins and Membrane-bounded Compartments. Planctomycetes and verrucomicrobia are evolutionarily distinct groups of bacteria which possess unusual cell structure and which share some significant genes important in cell biology with eukaryotes e.g. in verrucomicrobia the cytoskeleton protein tubulin. These bacteria are important for understanding the transition from no ....Molecular Cell Biology and Comparative Genomics Of Planctomycetes and Verrucomicrobia In Relation To Evolution Of Cytoskeletal Proteins and Membrane-bounded Compartments. Planctomycetes and verrucomicrobia are evolutionarily distinct groups of bacteria which possess unusual cell structure and which share some significant genes important in cell biology with eukaryotes e.g. in verrucomicrobia the cytoskeleton protein tubulin. These bacteria are important for understanding the transition from non-nucleated cells with simple cell division to nucleated cells with chromosome separation via cytoskeletal protein movement.The project will compare genomes of of planctomycetes and verrucomicrobia to determine their relationship, determine whether the tubulin homolog of verrucomicrobia can form cytoskeleton structures, and characterize the cytoskeleton of ammonium-oxidizing planctomycetes used in wastewater treatment.Read moreRead less
Roles for quorum sensing and biofilm formation by Vibrio cholerae in resistance to protozoan grazing. This research will benefit Australia through an increased fundamental understanding of how our model bacterium, Vibrio cholerae, survives in the environment. This could lead to the development of strategies that control bacterial biofilms, a significant medical and industrial concern. This project will also be of benefit through the training of postgraduate students in environmental microbiology ....Roles for quorum sensing and biofilm formation by Vibrio cholerae in resistance to protozoan grazing. This research will benefit Australia through an increased fundamental understanding of how our model bacterium, Vibrio cholerae, survives in the environment. This could lead to the development of strategies that control bacterial biofilms, a significant medical and industrial concern. This project will also be of benefit through the training of postgraduate students in environmental microbiology and is expected to result in the publication and presentation of data in quality journals and conferences, which increases the profile of Australian science.Read moreRead less
Autotransporter proteins of enterohemorrhagic Escherichia coli O157:H7. Escherichi (E.) coli O157:H7 has caused hundreds of outbreaks in the United States and United Kingdom. Although not currently a major problem in Australia, the emergence of E. coli O157:H7 here would have serious implications for our meat and livestock industry. This study will provide important information for the selection of vaccine antigens used to prevent the colonisation of cattle with E. coli O157:H7 and other diarrho ....Autotransporter proteins of enterohemorrhagic Escherichia coli O157:H7. Escherichi (E.) coli O157:H7 has caused hundreds of outbreaks in the United States and United Kingdom. Although not currently a major problem in Australia, the emergence of E. coli O157:H7 here would have serious implications for our meat and livestock industry. This study will provide important information for the selection of vaccine antigens used to prevent the colonisation of cattle with E. coli O157:H7 and other diarrhoeagenic E. coli serotypes. A direct outcome of this will be improved human health, as E. coli O157:H7 can cause life threatening infections in humans. The study will also examine the contribution of specific adhesins to biofilm formation; measures to prevent biofilm formation may reduce the persistence and spread of E. coli O157:H7 in the environment.Read moreRead less
Unravelling small RNA regulatory networks to target and control bacteria. Small RNA (sRNA) molecules are critical regulators of bacterial gene expression. These molecules control important phenotypes in the Gram-negative veterinary pathogen Pasteurella multocida. This project aims to identify the range of P. multocida sRNAs and to show how expression of these molecules changes under various growth conditions. Specifically, this project endeavours: to identify the mRNA targets of the sRNAs; to id ....Unravelling small RNA regulatory networks to target and control bacteria. Small RNA (sRNA) molecules are critical regulators of bacterial gene expression. These molecules control important phenotypes in the Gram-negative veterinary pathogen Pasteurella multocida. This project aims to identify the range of P. multocida sRNAs and to show how expression of these molecules changes under various growth conditions. Specifically, this project endeavours: to identify the mRNA targets of the sRNAs; to identify the mechanisms of sRNA-mRNA interaction; to build systems-biology models that describe the sRNA regulatory circuits; to design inhibitors capable of disrupting critical sRNA-mRNA interactions; and to use the new inhibitors to modulate specific phenotypes. The ability to precisely manipulate sRNA regulatory circuits could allow fine control of bacterial phenotypes and could be widely applicable.Read moreRead less
Molecular pumps and metabolism: regulatory interactions that control metal uptake and metabolism in bacteria. ABC (ATP-Binding Cassette) transporters are ubiquitous pumps that transport small molecules into and out of cells. This project investigates the novel roles of small-molecule-binding domains in the protein machine that drives the transporters for molybdenum and iron. They are predicted to interact with regulatory proteins and integrate transport with metabolism. It will provide insights ....Molecular pumps and metabolism: regulatory interactions that control metal uptake and metabolism in bacteria. ABC (ATP-Binding Cassette) transporters are ubiquitous pumps that transport small molecules into and out of cells. This project investigates the novel roles of small-molecule-binding domains in the protein machine that drives the transporters for molybdenum and iron. They are predicted to interact with regulatory proteins and integrate transport with metabolism. It will provide insights into metal trafficking and characterize gene regulatory networks that are important for bacterial pathogenicity and biological nitrogen fixation.Read moreRead less
A comprehensive analysis of the outer membrane, surface exposed and secreted proteome of Pasteurella multocida. Pasteurella multocida is the causative agent of a range of animal diseases. The molecular mechanisms of P. multocida pathogenesis are poorly understood and the current vaccines generally ineffective. We will identify all P. multocida outer membrane, surface exposed and secreted proteins expressed during natural infection, or under conditions which mimic natural infection, by a global p ....A comprehensive analysis of the outer membrane, surface exposed and secreted proteome of Pasteurella multocida. Pasteurella multocida is the causative agent of a range of animal diseases. The molecular mechanisms of P. multocida pathogenesis are poorly understood and the current vaccines generally ineffective. We will identify all P. multocida outer membrane, surface exposed and secreted proteins expressed during natural infection, or under conditions which mimic natural infection, by a global proteomics approach. We believe that secreted proteins and those found on the outer surface of the bacterial cell are likely to be crucial virulence determinants. The expected outcomes are the identification of a number of candidate vaccine antigens and an enhanced understanding of Pasteurella pathogenesis.Read moreRead less
Discovery of Novel Bacteriophage with the Capacity to Modulate Gut Bacteria. This project aims to experimentally validate the largest ever collection of bacterial viruses (bacteriophages) within the gut microbiome. This project expects to generate new knowledge in the area of bacteriophage biology and genomics by using the innovative approaches of wet-lab and bioinformatic genome analyses. Expect outcomes of this project include the discovery of novel phages using bioinformatics, wet-lab validat ....Discovery of Novel Bacteriophage with the Capacity to Modulate Gut Bacteria. This project aims to experimentally validate the largest ever collection of bacterial viruses (bacteriophages) within the gut microbiome. This project expects to generate new knowledge in the area of bacteriophage biology and genomics by using the innovative approaches of wet-lab and bioinformatic genome analyses. Expect outcomes of this project include the discovery of novel phages using bioinformatics, wet-lab validation of their activity and characterisation of their potential to contribute new bacterial host metabolism. This should provide benefits, such as advancement to our understanding of bacteriophages, improved bioinformatic software, and a characterised collection of commercially valuable bacterial strains and phages.Read moreRead less