Mapping cell wall and surface structures of Gram-positive cocci. The synthesis of the Gram-positive cell wall and protein transport are fundamental processes, the improved understanding of which will impact across a range of fields including microbiology, biochemistry and biotechnology, and the application and manipulation of Gram-positive bacteria in agriculture, industry and human health. In the long-term, the analysis of the Gram-positive ExPortal and cell wall will identify proteins that ma ....Mapping cell wall and surface structures of Gram-positive cocci. The synthesis of the Gram-positive cell wall and protein transport are fundamental processes, the improved understanding of which will impact across a range of fields including microbiology, biochemistry and biotechnology, and the application and manipulation of Gram-positive bacteria in agriculture, industry and human health. In the long-term, the analysis of the Gram-positive ExPortal and cell wall will identify proteins that may represent targets for therapeutic intervention. Additionally a precise understanding of the mechanisms of secretion of anchorless proteins will have an important impact in the biotechnology field, as new methodologies for the secretion of recombinant proteins of industrial value is a potential outcome.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
Nuclear structure and function in the nucleated planctomycete bacterium Gemmata obscuriglobus: a third cell plan for living organisms? The project will contribute knowledge of how cells such as those of animals and plants evolved from bacterial components. Origins of cell nuclei and pores in nuclear membranes will be studied via the simple eukaryote-like nucleus of the planctomycete Gemmata obscuriglobus, from Australian freshwater. Simple nuclear pore-like structures of G. obscuriglobus will he ....Nuclear structure and function in the nucleated planctomycete bacterium Gemmata obscuriglobus: a third cell plan for living organisms? The project will contribute knowledge of how cells such as those of animals and plants evolved from bacterial components. Origins of cell nuclei and pores in nuclear membranes will be studied via the simple eukaryote-like nucleus of the planctomycete Gemmata obscuriglobus, from Australian freshwater. Simple nuclear pore-like structures of G. obscuriglobus will help understanding nucleus function in animal cells, and such pores will give insight into 'minimal' composition needed for cell nuclei, and allow design of biological nanopores. The origin of the nucleus is a major problem in biology, and an Australian contribution to its solution will achieve international recognition. Read moreRead less
Autotransporter proteins of Escherichia coli. Autoransporters are a novel class of proteins associated with bacterial virulence properties such as adhesion, invasion and biofilm formation. Despite this, limited information is available on their functional role. The aim of this project is to characterize several of the autotransporter proteins from pathogenic E. coli. The likely contribution of these proteins to infection suggests that they are potential targets for strain attenuation and vaccine ....Autotransporter proteins of Escherichia coli. Autoransporters are a novel class of proteins associated with bacterial virulence properties such as adhesion, invasion and biofilm formation. Despite this, limited information is available on their functional role. The aim of this project is to characterize several of the autotransporter proteins from pathogenic E. coli. The likely contribution of these proteins to infection suggests that they are potential targets for strain attenuation and vaccine strain construction. Many of these proteins also mediate bacterial aggregation and are therefore targets for novel drugs that inhibit this process. The project will be carried out with a high profile partner from Denmark and will provide opportunity for travel and technology development. 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
Disulfide catalysis and protein folding in bacterial virulence. The molecular mechanisms that underpin disulfide bond formation have had a major impact on our understanding of protein folding and function. This project will make a major contribution to fundamental areas of disulfide catalysis pathways in bacterial pathogens and thus help maintain a strong international profile for Australian research in this field. The work will lead to training of research scientists and students in techniques ....Disulfide catalysis and protein folding in bacterial virulence. The molecular mechanisms that underpin disulfide bond formation have had a major impact on our understanding of protein folding and function. This project will make a major contribution to fundamental areas of disulfide catalysis pathways in bacterial pathogens and thus help maintain a strong international profile for Australian research in this field. The work will lead to training of research scientists and students in techniques that include molecular genetics, protein biochemistry and structural biology. Our findings may impact future directions for vaccine research on pathogens that cause life threatening infections in humans and therefore lead to improved health and reduced health care expenditure.Read moreRead less
NmlR-dependent thiol-based redox systems and their role in global stress responses in bacteria. All cells sense changes to their environment and respond by altering their metabolism. A major environmental change is oxidative stress which damages cells. Cells have the ability to sense oxidative stress and alter metabolic processes to defend against the damage that it elicits. This proposal will characterize a novel oxidative stress defense system that is found in a number of bacterial pathogens t ....NmlR-dependent thiol-based redox systems and their role in global stress responses in bacteria. All cells sense changes to their environment and respond by altering their metabolism. A major environmental change is oxidative stress which damages cells. Cells have the ability to sense oxidative stress and alter metabolic processes to defend against the damage that it elicits. This proposal will characterize a novel oxidative stress defense system that is found in a number of bacterial pathogens that need to defend themselves against attack by the host. The project may identify new ways to manage these bacterial pathogens. It may also provide an insight into oxidative stress defense processes that are linked to pathologies in humans.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
Control of Wolbachia replication: maintaining a stable symbiosis. This project will use a comparative genomics approach to better understand how Wolbachia infections of insects are able to maintain themselves in insects without causing pathology. The results will allow us to better understand a distinguishing characteristic of an intracellular symbiont, namely replication control. The results also have the potential to lead to new approaches to insect pest control through a better understanding ....Control of Wolbachia replication: maintaining a stable symbiosis. This project will use a comparative genomics approach to better understand how Wolbachia infections of insects are able to maintain themselves in insects without causing pathology. The results will allow us to better understand a distinguishing characteristic of an intracellular symbiont, namely replication control. The results also have the potential to lead to new approaches to insect pest control through a better understanding of how Wolbachia might be used to skew insect population age structure.Read moreRead less