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
Evolutionary and ecological complexity in an experimentally controlled environment. Understanding the capacity and mechanism of microbial evolution provides the framework for developing new strategies for preventing infectious disease. If we know how evolution works, it will be possible to hamper the capacity to evolve as a mechanism of preventing new diseases and controlling existing ones. This project will provide a mechanistic description of evolution in real time under controlled conditions. ....Evolutionary and ecological complexity in an experimentally controlled environment. Understanding the capacity and mechanism of microbial evolution provides the framework for developing new strategies for preventing infectious disease. If we know how evolution works, it will be possible to hamper the capacity to evolve as a mechanism of preventing new diseases and controlling existing ones. This project will provide a mechanistic description of evolution in real time under controlled conditions. This detailed information will be used in the education of the public and in debates about evolution. The project will also train at least five students in molecular and evolutionary microbiology, essential for facing future challenges.
Read moreRead less
Synthesis and assembly of bacterial repeat unit polysaccharides. Bacteria make an enormous range of surface polysaccharides. The complexity was first appreciated as antigenic diversity, but we now have hundreds of chemical structures and perhaps a hundred sequences of their gene clusters, but the number in nature must be many thousands. Our knowledge of gene function is growing but is not keeping up with the discovery of new sequences and structures. The aim is to determine structure and functio ....Synthesis and assembly of bacterial repeat unit polysaccharides. Bacteria make an enormous range of surface polysaccharides. The complexity was first appreciated as antigenic diversity, but we now have hundreds of chemical structures and perhaps a hundred sequences of their gene clusters, but the number in nature must be many thousands. Our knowledge of gene function is growing but is not keeping up with the discovery of new sequences and structures. The aim is to determine structure and function of key O antigen processing genes and the functions of a range of glycosyl transferases, and to use the information to generate novel gene clusters to synthesise novel polysaccharidesRead moreRead less
Elucidation of bacterial glycosylytransferase specificity. The benefits are involvement in the growth area of polysaccharide research, with potential for major industrial spin off. Polysaccharides are critical in all organisms as signalling, structural and storage compounds. Bacteria make a wide variety with extensive use of unusual sugars, some with uses from oil emulsifiers to food thickeners. The project is on the enzymes that assemble bacterial polysaccharides. We are world leaders in genet ....Elucidation of bacterial glycosylytransferase specificity. The benefits are involvement in the growth area of polysaccharide research, with potential for major industrial spin off. Polysaccharides are critical in all organisms as signalling, structural and storage compounds. Bacteria make a wide variety with extensive use of unusual sugars, some with uses from oil emulsifiers to food thickeners. The project is on the enzymes that assemble bacterial polysaccharides. We are world leaders in genetics of the gene clusters especially synthesis of the unusual sugars. We now aim to fill a major gap by determining which enzymes make which bonds, leading to options for new gene combinations and novel structures. We have a lead in research in this area and Australia gains if we maintain that lead.Read moreRead less