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
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
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
Stuctural analysis of RNA polymerase elongation complexes. RNA polymerase (RNAP) is an essential enzyme in all living cells. Its role is to convert the genetic information stored in genes into a message that can be converted into protein. Many additional factors are required to ensure that this enzyme functions correctly in the cell. The aim of this project is to obtain structural information on a bacterial RNAP complexed with an essential transcription factor called NusA. Using this information ....Stuctural analysis of RNA polymerase elongation complexes. RNA polymerase (RNAP) is an essential enzyme in all living cells. Its role is to convert the genetic information stored in genes into a message that can be converted into protein. Many additional factors are required to ensure that this enzyme functions correctly in the cell. The aim of this project is to obtain structural information on a bacterial RNAP complexed with an essential transcription factor called NusA. Using this information, plus data already obtained on the structure of this enzyme complexed with another essential factor called sigma, we will design small molecules to inhibit the interaction of these essential factors with polymerase. These molecules will serve as leads for the development of new antibiotics.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
Identifying Novel Biosynthetic Pathways in Mycobacteria using DNA Microarray Technology. DNA microarrays are a powerful new bioinformatics-based technology and an ideal tool for characterising complex biosynthetic pathways since the expression of all genes in the bacterial genome can be monitored in a single experiment. In this project we aim to construct and use a DNA microarray to identify novel biosynthetic pathways in mycobacteria. Of particular interest are pathways used to create compone ....Identifying Novel Biosynthetic Pathways in Mycobacteria using DNA Microarray Technology. DNA microarrays are a powerful new bioinformatics-based technology and an ideal tool for characterising complex biosynthetic pathways since the expression of all genes in the bacterial genome can be monitored in a single experiment. In this project we aim to construct and use a DNA microarray to identify novel biosynthetic pathways in mycobacteria. Of particular interest are pathways used to create components of the highly complex and poorly characterised cell wall. Since this structure is unique in the bacterial world, we expect to identify and characterise pathways that are unique to mycobacteria.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