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
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
Regulation of saxitoxin production in bacteria and algae. In Australia, toxic algal blooms have had a devastating impact on marine and freshwater resources. In collaboration with a biotechnology company, this project will develop exciting new methods based on information regarding the genetics of the toxin, to monitor and potentially mitigate the effects of algal blooms on water supplies and aquaculture industries. We will use this method to determine the impact of light and salinity in regulati ....Regulation of saxitoxin production in bacteria and algae. In Australia, toxic algal blooms have had a devastating impact on marine and freshwater resources. In collaboration with a biotechnology company, this project will develop exciting new methods based on information regarding the genetics of the toxin, to monitor and potentially mitigate the effects of algal blooms on water supplies and aquaculture industries. We will use this method to determine the impact of light and salinity in regulating toxin production in cyanobacteria and algae.Read moreRead less
In vitro evolution of more thermostable dextranases for the Australian sugar industry. Dextrans are polysaccharides that adversely affect the productivity of sugarcane mills. The Australian sugar industry currently imports dextranases to deal with this problem but they are not heat stable so the mills have run at lower temperatures than optimal. We have isolated dextranases from thermophilic microorganisms and aim to improve their performance by generating superior heat-stable dextranases using ....In vitro evolution of more thermostable dextranases for the Australian sugar industry. Dextrans are polysaccharides that adversely affect the productivity of sugarcane mills. The Australian sugar industry currently imports dextranases to deal with this problem but they are not heat stable so the mills have run at lower temperatures than optimal. We have isolated dextranases from thermophilic microorganisms and aim to improve their performance by generating superior heat-stable dextranases using in vitro evolution, creating new activity levels by random mutation and recombination. The research will be significant in providing novel enzymes for domestic use, allowing import substitution and an outcome will be the development of a product with export potential.
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