MOLECULAR BREEDING OF CYTOCHROME P450 ENZYMES. Cytochrome P450s are enzymes that catalyse an impressive array of oxidative transformations. However, there is little available data on how to modify their substrate specificity and generate tailored biocatalysts. We plan to use an emerging technology known as DNA shuffling to create libraries of P450s with varying activities. These will then be screened for enzymes that can catalyse the formation of indigo (a blue dye) and indirubin (a chemother ....MOLECULAR BREEDING OF CYTOCHROME P450 ENZYMES. Cytochrome P450s are enzymes that catalyse an impressive array of oxidative transformations. However, there is little available data on how to modify their substrate specificity and generate tailored biocatalysts. We plan to use an emerging technology known as DNA shuffling to create libraries of P450s with varying activities. These will then be screened for enzymes that can catalyse the formation of indigo (a blue dye) and indirubin (a chemotherapeutic agent). The enzymes that catalyse indigo formation will be useful in the production of coloured transgenic plants and those that produce indirubin will have a role in gene therapy.Read moreRead less
Nano-reactors: Protein cages as reusable scaffolds for designer enzymes. This project aims to develop robust protein cages derived from the coats of viruses to contain heat-stable P450 enzymes, for use as specialised protein bio-catalysts in chemical industries. A valuable chemical precursor of renewable bio-plastics will be produced from seed oils by enzymes, reducing the use of fossil fuels. This synthetic biology approach combines biotechnology, nanotechnology and protein engineering to estab ....Nano-reactors: Protein cages as reusable scaffolds for designer enzymes. This project aims to develop robust protein cages derived from the coats of viruses to contain heat-stable P450 enzymes, for use as specialised protein bio-catalysts in chemical industries. A valuable chemical precursor of renewable bio-plastics will be produced from seed oils by enzymes, reducing the use of fossil fuels. This synthetic biology approach combines biotechnology, nanotechnology and protein engineering to establish a plant-based platform biotechnology for using enzymes as catalysts to make high-value molecules. The project aims to show how to engineer clean, sustainable chemistry in designer nano-environments. This should make synthetic processes more sustainable and enhance advanced chemical manufacturing in Australia.Read moreRead less
Enantioselective nitrilases from filamentous fungi. The optical characteristics (chirality) of chemical precursors are important for many fine chemicals. Chiral intermediates are in high demand by the pharmaceutical and agrochemical industries for the preparation of bulk drug intermediates and agricultural products. Nitriles are attractive starting points but their conversion to corresponding amides and carboxylic acids generates significant wastes. Their hydrolysis can be performed under mil ....Enantioselective nitrilases from filamentous fungi. The optical characteristics (chirality) of chemical precursors are important for many fine chemicals. Chiral intermediates are in high demand by the pharmaceutical and agrochemical industries for the preparation of bulk drug intermediates and agricultural products. Nitriles are attractive starting points but their conversion to corresponding amides and carboxylic acids generates significant wastes. Their hydrolysis can be performed under mild conditions by enzymes termed nitrilases. We will work on fungal nitrilases as they present a globally attractive, yet untapped commercial target. The outcome for Applimex will be a suite of biocatalysts specific for the production of key intermediates for drug and agrochemical syntheses.Read moreRead less
Role of the proteasome in eradication of misfolded proteins in fungal cell factories. Filamentous fungi contribute to the well being of modern society as surrogate hosts for the synthesis of vaccines, hormones and enzymes for their application to health, agriculture, industry and the environment. However, attempts to express foreign proteins to the full potential of a given system have been disappointing. It is vital to understand unexplored molecular and physiological factors such as protein ....Role of the proteasome in eradication of misfolded proteins in fungal cell factories. Filamentous fungi contribute to the well being of modern society as surrogate hosts for the synthesis of vaccines, hormones and enzymes for their application to health, agriculture, industry and the environment. However, attempts to express foreign proteins to the full potential of a given system have been disappointing. It is vital to understand unexplored molecular and physiological factors such as protein quality control in the cell to take advantage of the global opportunities that recombinant gene expression indisputably offers in the form of unrestricted supply of proteins of social and economic value. The project will create novel IP and licensing opportunities for Australia.Read moreRead less
Biosynthesis of nonribosomal peptide toxins in cyanobacteria: A functional characterisation of microcystin synthetase. Microcystins are potent toxins and tumour promoters produced by cyanobacteria associated with blue-green algal blooms. This non-ribosomal peptide is produced by microcystin synthetase, a unique enzyme complex comprised of peptide synthetases, polyketide synthases, and integrated accessory enzymes. We have identified and characterised the extensive gene cluster encoding this enzy ....Biosynthesis of nonribosomal peptide toxins in cyanobacteria: A functional characterisation of microcystin synthetase. Microcystins are potent toxins and tumour promoters produced by cyanobacteria associated with blue-green algal blooms. This non-ribosomal peptide is produced by microcystin synthetase, a unique enzyme complex comprised of peptide synthetases, polyketide synthases, and integrated accessory enzymes. We have identified and characterised the extensive gene cluster encoding this enzyme. This project describes the biochemical characterisation of specific enzyme activities within microcystin synthetase and how they determine the final structure and toxicity of the many forms of microcystin. Interactions between this enzyme complex and its substrate amino acids will provide information for the genetic engineering of this and similar natural products.Read moreRead less
Role of a novel zinc-binding motif in the structure-function of deubiquitinating enzymes. The ubiquitin pathway destroys many proteins that control cell function and growth, by attaching ubiquitin to them and marking them for degradation. Deubiquitinating enzymes (DUBs) regulate protein destruction by controlling the amount of ubiquitin attached. DUBs and the ubiquitin pathway can also be manipulated in biotechnology applications. However, very little is known about the structure/function of DUB ....Role of a novel zinc-binding motif in the structure-function of deubiquitinating enzymes. The ubiquitin pathway destroys many proteins that control cell function and growth, by attaching ubiquitin to them and marking them for degradation. Deubiquitinating enzymes (DUBs) regulate protein destruction by controlling the amount of ubiquitin attached. DUBs and the ubiquitin pathway can also be manipulated in biotechnology applications. However, very little is known about the structure/function of DUBs. We have identified a new zinc-binding motif in DUBs, and we will explore how this contributes to their structure, and interactions with other proteins. This will significantly enhance our knowledge of how DUBs function in both biotechnology and in controlling cell function.Read moreRead less
The molecular biology and biochemistry of bacterial manganese oxidation. This project will further the understanding of bacterial manganese (Mn2+) oxidation. A multi-disciplinary approach will be used to further investigate the genetics and biochemistry of the Mn2+-oxidising systems of Pseudomonas putida, Leptothrix sp. and Pedomicrobium sp. This work will focus in particular on comparing the Mn2+-oxidising systems from unrelated bacteria. A combination of molecular biology, protein biochemis ....The molecular biology and biochemistry of bacterial manganese oxidation. This project will further the understanding of bacterial manganese (Mn2+) oxidation. A multi-disciplinary approach will be used to further investigate the genetics and biochemistry of the Mn2+-oxidising systems of Pseudomonas putida, Leptothrix sp. and Pedomicrobium sp. This work will focus in particular on comparing the Mn2+-oxidising systems from unrelated bacteria. A combination of molecular biology, protein biochemistry and spectroscopy will be used. This will be the first time that the enzymes of bacterial Mn2+-oxidation will have been characterised in such detail and will lead to a greater understanding of the process of bacterial manganese oxidation.Read moreRead less
Understanding mechanistic and systemic regulation of protein prenyltransferases. The proposed research will expand our understanding of lipid-conjugating enzymes that are critical for a multitude of normal cellular functions. We seek to reveal the basic workings of cells and help to explain the development and complexity of signalling networks in eukaryotic evolution. The findings will enable us to explore and exploit the catalytic properties of these lipid-related enzymes for applications in bi ....Understanding mechanistic and systemic regulation of protein prenyltransferases. The proposed research will expand our understanding of lipid-conjugating enzymes that are critical for a multitude of normal cellular functions. We seek to reveal the basic workings of cells and help to explain the development and complexity of signalling networks in eukaryotic evolution. The findings will enable us to explore and exploit the catalytic properties of these lipid-related enzymes for applications in biotechnology. The ultimate aim is to create novel technologies for protein production, modification and analysis that will accelerate the pace of discovery in protein research, basic cell and organism biology, diagnostics, biotechnology and drug discovery. Read moreRead less
Mapping networks governing cell state plasticity: how, where and when? Single cell organisms are the basic unit of life, yet, if they had not developed the ability to change cell states we would not exist today. Changing cell states lies at the core of almost every developmental and disease process in multicellular organisms. Building upon our fundamental discovery that stem cells and non-stem cells readily interconvert, we will now incorporate innovative cell systems and the development of our ....Mapping networks governing cell state plasticity: how, where and when? Single cell organisms are the basic unit of life, yet, if they had not developed the ability to change cell states we would not exist today. Changing cell states lies at the core of almost every developmental and disease process in multicellular organisms. Building upon our fundamental discovery that stem cells and non-stem cells readily interconvert, we will now incorporate innovative cell systems and the development of our new multi-layered systems biology strategy to elucidate the first comprehensive understanding of the cell biology that underlies cell state changes. These studies are a major step toward understanding the fundamentals of life. Read moreRead less