Functional analysis of Bacillus thuringiensis crystal toxins. Pore-forming toxins, such as anthrax, hemolysin, cholera and diphtheria toxins, are among the most virulent microbial toxins, posing a threat to humans and lifestock. We are using a novel functional approach to test possible lectin and antimicrobial peptide functions of a typical and economically important pore-forming toxin, the crystal endotoxin from Bacillus thuringiensis, to examine why toxicity of the lectin-containing toxin is ....Functional analysis of Bacillus thuringiensis crystal toxins. Pore-forming toxins, such as anthrax, hemolysin, cholera and diphtheria toxins, are among the most virulent microbial toxins, posing a threat to humans and lifestock. We are using a novel functional approach to test possible lectin and antimicrobial peptide functions of a typical and economically important pore-forming toxin, the crystal endotoxin from Bacillus thuringiensis, to examine why toxicity of the lectin-containing toxin is restricted to invertebrates only, while the amphipathic peptide alone is also toxic to many vertebrate cells. The outcome of these experiments has important implications for the sustainable use of biopesticides and for the prevention and containment of infectious diseases.Read moreRead less
Theoretical and computational approaches to accurately predict the structures of a unique family of circular and knotted proteins. The primary outcome will be a fundamental new knowledge on cyclotide structures and a new protein engineering method to design stabilised proteins. Because cyclotides have significantly higher stabilities than conventional proteins, they have a range of pharmaceutical and agricultural applications. Both fields of use have the potential for very great economic and soc ....Theoretical and computational approaches to accurately predict the structures of a unique family of circular and knotted proteins. The primary outcome will be a fundamental new knowledge on cyclotide structures and a new protein engineering method to design stabilised proteins. Because cyclotides have significantly higher stabilities than conventional proteins, they have a range of pharmaceutical and agricultural applications. Both fields of use have the potential for very great economic and social benefits for Australia. From a pharmaceutical perspective our computing development will greatly facilitate the design of stabilised peptide-based drugs using the cyclotide framework. Such drugs have potential sales of several billion dollars per annum and the royalty returns from successful commercialisation of IP can be substantial.Read moreRead less
Structural studies of plant disease resistance proteins. Plant cells have evolved a gene-for-gene disease resistance mechanism, involving an interaction of a plant-derived receptor with a specific pathogen-derived molecule. Currently, plant breeders are restricted to the resistance genes available in particular crop species or sexually compatible relatives. In the last few years, several plant disease resistance genes have been identified, providing a foundation for studying the molecular basis ....Structural studies of plant disease resistance proteins. Plant cells have evolved a gene-for-gene disease resistance mechanism, involving an interaction of a plant-derived receptor with a specific pathogen-derived molecule. Currently, plant breeders are restricted to the resistance genes available in particular crop species or sexually compatible relatives. In the last few years, several plant disease resistance genes have been identified, providing a foundation for studying the molecular basis of the resistance process. We propose to obtain three-dimensional structural information on representative R proteins and their ligand complexes. This will form the basis for modifying existing resistance genes to confer resistance to new diseases, resulting in large economic benefits.Read moreRead less
Molecular basis of the interaction between plant disease resistance proteins and pathogen avirulence proteins. Management of crop diseases involves the integrated use of resistant cultivars and the application of chemical pesticides. Many diseases, however, including rust, continue to pose an economically significant threat to agricultural productivity in Australia. The research outlined in this proposal aims to understand the mechanisms, at a molecular and structural level, that enable resistan ....Molecular basis of the interaction between plant disease resistance proteins and pathogen avirulence proteins. Management of crop diseases involves the integrated use of resistant cultivars and the application of chemical pesticides. Many diseases, however, including rust, continue to pose an economically significant threat to agricultural productivity in Australia. The research outlined in this proposal aims to understand the mechanisms, at a molecular and structural level, that enable resistant plants to detect and respond to pathogen attack. The outcomes of this currently unavailable fundamental understanding will enable new, durable and more effective resistance genes to be engineered. Therefore, the work has significant economic and environmental implications for agricultural crop plant productivity in this country.Read moreRead less
Mechanisms and management of inducible tolerance to synthetic insecticides and Bacillus thuringiensis (Bt)-formulations in Australian populations of diamondback moth. Insects have a cunning ability to respond to damaging environments by evolving genetic resistance or mobilising metabolic tolerance mechanisms. Recent observations of inducible tolerance to synthetic and biopesticides, which can be transmitted to offspring by a maternal effect has the potential to cause ecological and economic prob ....Mechanisms and management of inducible tolerance to synthetic insecticides and Bacillus thuringiensis (Bt)-formulations in Australian populations of diamondback moth. Insects have a cunning ability to respond to damaging environments by evolving genetic resistance or mobilising metabolic tolerance mechanisms. Recent observations of inducible tolerance to synthetic and biopesticides, which can be transmitted to offspring by a maternal effect has the potential to cause ecological and economic problems in agricultural production. We will use field-collected Diamondback moth (DBM), a major insect pest in canola and brassica vegetable crops, to investigate the genetic implications of inducible tolerance for the integrated management of DBM and for the design of new resistance management strategies.Read moreRead less
Beneficial arthropods in Coonawarra vineyards and sustainable grape production. Many species of pest and beneficial arthropods live in vines and groundcover of vineyards. Vignerons often devote considerable effort to sustain populations of what they believe to be beneficial arthropods. However, the types of natural enemies and techniques to enhance their effectiveness are poorly known. This project aims to identify and quantify the role of natural enemies in controlling the main pest in Coonawar ....Beneficial arthropods in Coonawarra vineyards and sustainable grape production. Many species of pest and beneficial arthropods live in vines and groundcover of vineyards. Vignerons often devote considerable effort to sustain populations of what they believe to be beneficial arthropods. However, the types of natural enemies and techniques to enhance their effectiveness are poorly known. This project aims to identify and quantify the role of natural enemies in controlling the main pest in Coonawarra vineyards, identify their food and shelter requirements, and improve management practices and other techniques to optimise populations of beneficial species. The significance of this project is that it will enable the promotion of insecticide-free production of winegrapes in the Coonawarra.Read moreRead less
Novel vaccines and serotyping scheme for Haemophilus parasuis. Glasser's disease, caused by the bacterium Haemophilus parasuis, is a significant problem in Australian and overseas pig industries. Current approaches to the management of Glassers disease utilise antibacterials and also vaccines. However, antibacterials are of limited effectiveness in juvenile pigs (weaners) that are difficult to medicate other than by injection, and current vaccines are only protective against the serotypes incl ....Novel vaccines and serotyping scheme for Haemophilus parasuis. Glasser's disease, caused by the bacterium Haemophilus parasuis, is a significant problem in Australian and overseas pig industries. Current approaches to the management of Glassers disease utilise antibacterials and also vaccines. However, antibacterials are of limited effectiveness in juvenile pigs (weaners) that are difficult to medicate other than by injection, and current vaccines are only protective against the serotypes included in the vaccine. We propose to examine the immune response to natural infection and identify potential vaccine candidates which will then be tested in vaccine trials. The APAI will focus on developing a DNA-based typing scheme for H. parasuis.Read moreRead less
Global genetic regulation of carbon metabolism in filamentous fungi. Fungi are of great importance in medicine, agriculture and industry. They are used extensively for food, antibiotic and chemical production and, increasingly, for generating cheap substrates for bioethanol. However many are serious pathogens of plants and humans. Understanding how fungi control their metabolism is of fundamental importance for their more effective use or control. This project takes advantage of a fungus that is ....Global genetic regulation of carbon metabolism in filamentous fungi. Fungi are of great importance in medicine, agriculture and industry. They are used extensively for food, antibiotic and chemical production and, increasingly, for generating cheap substrates for bioethanol. However many are serious pathogens of plants and humans. Understanding how fungi control their metabolism is of fundamental importance for their more effective use or control. This project takes advantage of a fungus that is easily studied in the laboratory by advanced genetic techniques to identify the ways in which genes are turned on and off in response to changes in the nutrients available. By comparing DNA sequences the results are readily applied to fungi of economic importance.Read moreRead less
A novel approach to fighting fungal infections: targeted disruption of hydrophobin monolayers. Fungal infestations of important crops such as cotton cause large economic losses to Australian agriculture while in the medical sector, fungal infections are responsible for high levels of mortality in immunocompromised patients. Our research will provide a new approach to fighting fungal infections by targeting the hydrophobin proteins, which form a robust coating on fungal aerial structures, such as ....A novel approach to fighting fungal infections: targeted disruption of hydrophobin monolayers. Fungal infestations of important crops such as cotton cause large economic losses to Australian agriculture while in the medical sector, fungal infections are responsible for high levels of mortality in immunocompromised patients. Our research will provide a new approach to fighting fungal infections by targeting the hydrophobin proteins, which form a robust coating on fungal aerial structures, such as spores. This layer is critical for fungal growth and reproduction and confers water resistance and tolerance to harsh conditions. Our work seeks to develop reagents that can specifically block regions on the protein that are responsible for forming this coating.
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Cell-free immune reactions and suppression. Insects pests and insect vectors of diseases are managed by toxic substances, but insects have a cunning ability to persist. How pesticide-tolerant insect pests recognise and inactivate chemical and biological toxins is poorly understood. While vertebrates with a closed circulatory system use coagulation reactions mainly for wound-healing, invertebrates employ cell-free aggregation reactions for the sequestration and inactivation of potentially damagin ....Cell-free immune reactions and suppression. Insects pests and insect vectors of diseases are managed by toxic substances, but insects have a cunning ability to persist. How pesticide-tolerant insect pests recognise and inactivate chemical and biological toxins is poorly understood. While vertebrates with a closed circulatory system use coagulation reactions mainly for wound-healing, invertebrates employ cell-free aggregation reactions for the sequestration and inactivation of potentially damaging objects and substances. We use insect plasma to dissect recognition and inactivation of damaging objects and substances with the aim to understand tolerance and its inhibition to design novel strategies in delaying tolerance to pesticides in insect pests.Read moreRead less