Snapshots of an enzyme in action: structural and mechanistic studies on the catalytic cycle of Escherichia coli ketol-acid reductoisomerase. Enzymes are required for almost every process that occurs in a living organism. For this reason, understanding how enzymes work is essential if we are to understand life itself. In this project we will investigate the enzyme KARI by capturing a series of snapshots of its atomic structure as it progresses through its working cycle. In addition, we will make ....Snapshots of an enzyme in action: structural and mechanistic studies on the catalytic cycle of Escherichia coli ketol-acid reductoisomerase. Enzymes are required for almost every process that occurs in a living organism. For this reason, understanding how enzymes work is essential if we are to understand life itself. In this project we will investigate the enzyme KARI by capturing a series of snapshots of its atomic structure as it progresses through its working cycle. In addition, we will make a series of small alterations to the atomic structure that will allow us to understand how the individual parts work together.Read moreRead less
Structure and inhibition of acetohydroxyacid synthase. Acetohydroxyacid synthase (AHAS) has been identified as the target for several widely used herbicides known as the sulfonylureas and imidazolinones. World-wide, these two herbicides account for $US2 billion in annual sales. The aim is to determine the three-dimensional structure of AHAS from several sources and in complex with these herbicides. Furthermore, AHAS appears to be an excellent target for the development of antibacterial compounds ....Structure and inhibition of acetohydroxyacid synthase. Acetohydroxyacid synthase (AHAS) has been identified as the target for several widely used herbicides known as the sulfonylureas and imidazolinones. World-wide, these two herbicides account for $US2 billion in annual sales. The aim is to determine the three-dimensional structure of AHAS from several sources and in complex with these herbicides. Furthermore, AHAS appears to be an excellent target for the development of antibacterial compounds and fungicides. Knowledge of the three dimensional structures of these enzymes will be important in the rational design of more effective inhibitors with improved selectivity.Read moreRead less
Molecular mechanisms of pilin glycosylation in Neisseria: a model system for protein glycosylation in bacteria. The disease causing bacteria Neisseria meningitidis and Neisseria gonorrhoeae are important human pathogens. Cell surface structures, called pili, are known to be important in allowing the bacteria to stick to host cells. Genetic and structural studies have identified that the protein subunits, which make up pili, are glycosylated - modified by the addition of sugars. Until recently ....Molecular mechanisms of pilin glycosylation in Neisseria: a model system for protein glycosylation in bacteria. The disease causing bacteria Neisseria meningitidis and Neisseria gonorrhoeae are important human pathogens. Cell surface structures, called pili, are known to be important in allowing the bacteria to stick to host cells. Genetic and structural studies have identified that the protein subunits, which make up pili, are glycosylated - modified by the addition of sugars. Until recently glycosylation of Gram-negative bacterial proteins was not thought to occur, however our recent work with these bacteria, and other groups studying Pseudomonas and Campylobacter, have shown that this process may be widespread. In our previous studies, we have identified and analysed a number of genes involved in pili glycosylation, in bacteria, which make known sugar structures. We have used this information to developed models for how the biochemistry and physiology of the glycosylation system may work. With a well-established structure and many genes already identified, glycosylation in Neisseria represents the best available model system to study this novel and important process. In the proposed study we describe experiments planned to test our models and reveal the molecular detail of this process. This study could lead to major advances in our understanding of this process and, when understood, may have future applications in biotechnology.Read moreRead less
Mechanistic Studies of Dimethylsulfide Dehydrogenase: A Novel Bacterial Molybdoenzyme. The aim of this proposal is to use electrochemical, spectroscopic and molecular biological techniques to understand the mechanism of action of the enzyme dimethylsulfide dehydrogenase. This enzyme is representative of an major group of molybdenum-containing enzymes that have importance in microbial biotransformations. The project will provide fundamental information about a multi-redox centre protein that has ....Mechanistic Studies of Dimethylsulfide Dehydrogenase: A Novel Bacterial Molybdoenzyme. The aim of this proposal is to use electrochemical, spectroscopic and molecular biological techniques to understand the mechanism of action of the enzyme dimethylsulfide dehydrogenase. This enzyme is representative of an major group of molybdenum-containing enzymes that have importance in microbial biotransformations. The project will provide fundamental information about a multi-redox centre protein that has potential application in biosensors and biocatalysis.Read moreRead less
Linkage Infrastructure, Equipment And Facilities - Grant ID: LE0344441
Funder
Australian Research Council
Funding Amount
$390,000.00
Summary
New Generation Metalloenzyme Magnetic Circular Dichroism Spectrometer Systems. Funding is sought to enhance the existing collaborations between UQ, ANU, Sydney and other universities in the study of metal-centred molecules of biological interest through the construction of advanced magnetic circular dichroism (MCD) spectrometers. These facilities will be the best instruments of their kind, and will enable researchers at Australian institutions to enhance the quality of their research and remain ....New Generation Metalloenzyme Magnetic Circular Dichroism Spectrometer Systems. Funding is sought to enhance the existing collaborations between UQ, ANU, Sydney and other universities in the study of metal-centred molecules of biological interest through the construction of advanced magnetic circular dichroism (MCD) spectrometers. These facilities will be the best instruments of their kind, and will enable researchers at Australian institutions to enhance the quality of their research and remain internationally competitive through the application of modern MCD spectroscopic techniques to the study of metal-centred biomolecules. These facilities will drive a number of programs in the area of metalloenzyme and photosystem II research.Read moreRead less
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
Monolayer crystallization of membrane proteins. Membrane proteins comprise 25-40% of all proteins and conduct a myriad of finely tuned reactions in every cell. Despite their importance and diversity only ~40 membrane protein structures have been solved, due to the difficulty of producing high quality 2D and 3D crystals. We propose to develop and use the new monolayer crystallization technique, which employs a lipid monolayer as a crystallization template for 2D crystal production. A number of ....Monolayer crystallization of membrane proteins. Membrane proteins comprise 25-40% of all proteins and conduct a myriad of finely tuned reactions in every cell. Despite their importance and diversity only ~40 membrane protein structures have been solved, due to the difficulty of producing high quality 2D and 3D crystals. We propose to develop and use the new monolayer crystallization technique, which employs a lipid monolayer as a crystallization template for 2D crystal production. A number of important membrane proteins are available for these structural studies including ABC transporters, Caveolin-3 and the NS1 protein of Dengue virus, all of which are difficult to crystallize using conventional techniques.Read moreRead less
Linkage Infrastructure, Equipment And Facilities - Grant ID: LE0561041
Funder
Australian Research Council
Funding Amount
$347,358.00
Summary
A New Generation Biosensor and Fluorescence Facility for Proteomics. The complete DNA sequence (the genome) is now known for many organisms and advances are being made to identify the complement of messenger RNA (the transcriptome) and the resultant collection of proteins (the proteome). The genome is largely fixed while the transcriptome and proteome differ between cell types in an organism and constantly vary to adapt the cell to changing conditions. The mediators of these variations are prote ....A New Generation Biosensor and Fluorescence Facility for Proteomics. The complete DNA sequence (the genome) is now known for many organisms and advances are being made to identify the complement of messenger RNA (the transcriptome) and the resultant collection of proteins (the proteome). The genome is largely fixed while the transcriptome and proteome differ between cell types in an organism and constantly vary to adapt the cell to changing conditions. The mediators of these variations are proteins, interacting with each other and with signal molecules. The next frontier in molecular biology is to identify and quantify these protein interactions. Our two institutions have a very large cohort of biologists whose research on proteins would be greatly facilitated by the Biacore 3000 and the ISS K2.Read moreRead less
An Integrated Approach Towards Development of Highly Specific Chemotherapeutics. Many diseases are caused or can be treated by modifying the activities of particular enzymes. Molecules that affect enzymatic activities have potential as therapeutic agents. A successful approach to the discovery of new drug molecules is to design them based on very detailed knowledge of how the target enzyme works. In this project, a highly motivated team of scientists will use state of the art instruments and the ....An Integrated Approach Towards Development of Highly Specific Chemotherapeutics. Many diseases are caused or can be treated by modifying the activities of particular enzymes. Molecules that affect enzymatic activities have potential as therapeutic agents. A successful approach to the discovery of new drug molecules is to design them based on very detailed knowledge of how the target enzyme works. In this project, a highly motivated team of scientists will use state of the art instruments and their combined creativity to understand the intimate details of how one large group of enzymes work. The enzymes selected are the bimetallic hydrolases, many of which are associated with disorders including osteoporosis, mental illnesses, cystic fibrosis and various types of cancer.Read moreRead less
BIOCATALYSTS MINED FROM CYTOCHROME P450 LIBRARIES: AN INNOVATIVE TOOL FOR ACCELERATING DRUG DEVELOPMENT. The cytochrome P450s (P450s) are a family of enzymes that are perhaps the most versatile biological catalysts known. DNA shuffling is an emerging technique that takes the genes encoding families of enzymes and creates libraries of catalysts with both improved and novel properties. We will obtain proof of concept that shuffled P450 libraries can be screened and optimized for use as biocatalys ....BIOCATALYSTS MINED FROM CYTOCHROME P450 LIBRARIES: AN INNOVATIVE TOOL FOR ACCELERATING DRUG DEVELOPMENT. The cytochrome P450s (P450s) are a family of enzymes that are perhaps the most versatile biological catalysts known. DNA shuffling is an emerging technique that takes the genes encoding families of enzymes and creates libraries of catalysts with both improved and novel properties. We will obtain proof of concept that shuffled P450 libraries can be screened and optimized for use as biocatalysts in drug development. The methodologies developed here will overcome two critical bottlenecks in current drug development: the optimisation and metabolic profiling of new drug candidates. This will yield important benefits in accelerating the optimisation and safety testing of drugs under development.Read moreRead less