Does testosterone produce duds or studs? A performance-based examination of the Immunocompetence Handicap Hypothesis. The evolutionary persistence of testosterone (T) as a vertebrate reproductive hormone is viewed as a double-edged sword. On the one hand T secretion is required for development and expression of appropriate reproductive functions. On the other hand T is known to suppress immune functions and is thus considered a liability to male health. We are examining an alternate hypothesis: ....Does testosterone produce duds or studs? A performance-based examination of the Immunocompetence Handicap Hypothesis. The evolutionary persistence of testosterone (T) as a vertebrate reproductive hormone is viewed as a double-edged sword. On the one hand T secretion is required for development and expression of appropriate reproductive functions. On the other hand T is known to suppress immune functions and is thus considered a liability to male health. We are examining an alternate hypothesis: that T-induced immunosuppression benefits breeding males by protecting their physical performance levels during immune challenge. We will examine this hypothesis by quantifying the interactive effects of T and immune challenge on the aerobic capacity of male birds.Read moreRead less
The Fine Tuned Physiology of Microaerophilic Gastric Spirilla. The aim of the project is to understand the molecular basis of fundamental properties of the physiology of enterogastric spiral bacteria of the genera Campylobacter and Helicobacter. The characteristics of these obligate microaerophiles which will be investigated are their aerobic respiratory chains, the special metabolites and enzymes involved in thiol-disulphide redox balance, and their essential requirement for carbon dioxide. Mic ....The Fine Tuned Physiology of Microaerophilic Gastric Spirilla. The aim of the project is to understand the molecular basis of fundamental properties of the physiology of enterogastric spiral bacteria of the genera Campylobacter and Helicobacter. The characteristics of these obligate microaerophiles which will be investigated are their aerobic respiratory chains, the special metabolites and enzymes involved in thiol-disulphide redox balance, and their essential requirement for carbon dioxide. Microaerobes include some bacteria, archea and protozoa. Realisation of the widespread habitats and importance of microaerophiles, has led recently to a vigorous interest in understanding their physiology. Knowledge of the basic properties of microaerophily has potential applications to Environmental Microbiology, Agriculture, Industrial Microbiology, Veterinary Science and Medicine.Read moreRead less
Structural analysis and functional inactivation of bacterial transcription complexes. RNA polymerase 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. As such, the bacterial RNA polymerase represents an ideal target for the development of new antibiotics which will be important in maintaining the health of the Australian community and also in protecting the community from the very real thr ....Structural analysis and functional inactivation of bacterial transcription complexes. RNA polymerase 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. As such, the bacterial RNA polymerase represents an ideal target for the development of new antibiotics which will be important in maintaining the health of the Australian community and also in protecting the community from the very real threat of bioterrorism organisms such as anthrax. This project is designed to identify molecules for development as new antibiotics that are effective against RNA polymerase.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
Plasmid maintenance and interactions with the host cell and its genome. Plasmids are extrachromosomal genetic elements that play a central role in the evolution of bacteria. They are the most dynamic component of the bacterial genome, augmenting the host chromosome by conferring a range of significant phenotypes that facilitate environmental adaptation. This project aims to elucidate fundamental aspects of the relationship between plasmids and their bacterial hosts. Significant outcomes include ....Plasmid maintenance and interactions with the host cell and its genome. Plasmids are extrachromosomal genetic elements that play a central role in the evolution of bacteria. They are the most dynamic component of the bacterial genome, augmenting the host chromosome by conferring a range of significant phenotypes that facilitate environmental adaptation. This project aims to elucidate fundamental aspects of the relationship between plasmids and their bacterial hosts. Significant outcomes include understanding the molecular basis of efficient plasmid inheritance in bacterial populations, and exploration of the innovative hypothesis that plasmids modulate expression of the host chromosome, a possibility that would profoundly alter our view of how plasmids influence host phenotype.Read moreRead less
A Unique Target in the Purine Biosynthesis of the Pathogen Helicobacter pylori. The uptake systems of purine and analogues of the human pathogen Helicobacter pylori will be characterised because they can be utilised to introduce cytotoxic compounds into the cells. The first step in de novo purine biosynthesis of the bacterium is catalysed by two different enzymes, which are components of other biosynthetic pathways. These unique properties make them excellent potential therapeutic targets. Their ....A Unique Target in the Purine Biosynthesis of the Pathogen Helicobacter pylori. The uptake systems of purine and analogues of the human pathogen Helicobacter pylori will be characterised because they can be utilised to introduce cytotoxic compounds into the cells. The first step in de novo purine biosynthesis of the bacterium is catalysed by two different enzymes, which are components of other biosynthetic pathways. These unique properties make them excellent potential therapeutic targets. Their individual combined activities in purine biosynthesis will be characterised in situ and in vitro. Isogenic mutants with inactivated genes encoding for these enzymes will be constructed to investigate their role in the survival of the organism.Read moreRead less
Evolution of viviparity in reptiles: the fundamental role of junctional complexes. This project utilises unique Australian reptile fauna to understand global questions in fundamental biology. We will discover basic biological information on native species, which will be important in future conservation of Australian ecosystems and animals and ultimately in helping to maintain Australia's biodiversity. The project also provides training opportunities for graduate and undergraduate students in ....Evolution of viviparity in reptiles: the fundamental role of junctional complexes. This project utilises unique Australian reptile fauna to understand global questions in fundamental biology. We will discover basic biological information on native species, which will be important in future conservation of Australian ecosystems and animals and ultimately in helping to maintain Australia's biodiversity. The project also provides training opportunities for graduate and undergraduate students in several different research methods that are widely applicable in the more general Australian workforce. Because the research work is genuinely cross-disciplinary research, its findings are applicable to both biological and medically oriented technologies.Read moreRead less
Uterodomes and the evolution of viviparity. We will test the hypothesis that uterodomes, which are cell structures unique to the early pregnant uterus in mammals, and the cellular changes accompanying their development, are essential to the evolution of viviparity in amniotes. The proposal stems from our recent discovery that uterodomes develop in the uteri of viviparous lizards as well as in mammals, suggesting key commonalities at the cellular level in the evolution of live birth across amnio ....Uterodomes and the evolution of viviparity. We will test the hypothesis that uterodomes, which are cell structures unique to the early pregnant uterus in mammals, and the cellular changes accompanying their development, are essential to the evolution of viviparity in amniotes. The proposal stems from our recent discovery that uterodomes develop in the uteri of viviparous lizards as well as in mammals, suggesting key commonalities at the cellular level in the evolution of live birth across amniote vertebrates. We will take advantage of the unique combination of placental types among Australian lizards, including a species with both oviparous and viviparous populations.Read moreRead less
Comparative Biogeography of Australasian biota. Establishing an internationally recognised biogeographical research program will help scientists, policy makers and the public understand the past and future distribution patterns of the plants and animals of Australia. Discovering these patterns will help conservation biologists and government implement the right policies and practices to deal with biodiversity loss and climate change.
Conserving our native carnivores: the application of molecular genetics to the conservation management of quolls. Quolls, the largest native mammalian predators on mainland Australia, occupy a pivotal ecological niche. All species are declining and are threatened by a variety of interacting environmental processes. This program brings together seven wildlife agencies in a nationwide partnership for understanding and protecting quolls. We will provide new genetic data to test current populatio ....Conserving our native carnivores: the application of molecular genetics to the conservation management of quolls. Quolls, the largest native mammalian predators on mainland Australia, occupy a pivotal ecological niche. All species are declining and are threatened by a variety of interacting environmental processes. This program brings together seven wildlife agencies in a nationwide partnership for understanding and protecting quolls. We will provide new genetic data to test current population and conservation theories using four species of quolls as model taxa to inform us about past histories of populations and to measure parameters of importance to on-ground managers. Results of these projects will help guide management practices for both short- and long-term conservation of these species.Read moreRead less