TOWARDS A COMPLETE DESCRIPTION OF HOW ENZYMES WORK: development of simulation methods and protocols, blind test predictions, and experimental validation. Enzymes catalyze quite fantastic chemistry under mild physiological conditions. Many special chemical concepts (such as "transition-state stabilization" and "entropy-enthalpy compensation") proposed to explain these powers are unnecessary. Uniquely for a catalyst, these powers are integral to the structure, properties and dynamics of the protei ....TOWARDS A COMPLETE DESCRIPTION OF HOW ENZYMES WORK: development of simulation methods and protocols, blind test predictions, and experimental validation. Enzymes catalyze quite fantastic chemistry under mild physiological conditions. Many special chemical concepts (such as "transition-state stabilization" and "entropy-enthalpy compensation") proposed to explain these powers are unnecessary. Uniquely for a catalyst, these powers are integral to the structure, properties and dynamics of the protein, as constrained and selected by evolution. The question is how do they work? Answering this requires energetic and thermodynamic analysis beyond current experimental techniques, but accessible by computer simulation. We aim to develop a robust toolkit of simulation methods and protocols, blind test them by predicting the mechanism of a new enzyme, with followup experimental validation.
Read moreRead less
Importance of conformational and electrostatic contributions in simulations of enzyme reaction mechanisms. The research will contribute to the development of biomolecular simulation in Australia by demonstrating its potential to complement experiment, and also promote the effective use of APAC (Australian national supercomputer facilities) resources by providing advanced programs and computational protocols for other researchers. It will assist the diffusion of computational biology technology i ....Importance of conformational and electrostatic contributions in simulations of enzyme reaction mechanisms. The research will contribute to the development of biomolecular simulation in Australia by demonstrating its potential to complement experiment, and also promote the effective use of APAC (Australian national supercomputer facilities) resources by providing advanced programs and computational protocols for other researchers. It will assist the diffusion of computational biology technology into industrial applications such as rational drug design and protein engineering, as, for example, in our associated Linkage project grant, and provide novel insights into protein engineering and other sorts of design, which transcend concepts currently used in biomimetic chemistry.Read moreRead less
Characterising and exploiting hydrogen tunnelling in environmentally and medically important enzymes. Theory and experiment will be used to study environmentally and medically important enzymes, and quantify the role that hydrogen tunnelling plays in their activity. The project will determine the basis of their remarkable ability to catalyse chemical reactions, and to engineer and design more efficient proteins and pharmaceuticals.
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
Mammalian histidine kinase: its characterisation and role in hepatic cellular proliferation. Protein kinases regulate all aspects of cellular metabolism, but there is a class of protein kinase, histidine kinases, which exists in mammalian cells, about which remarkably little is understood. This project will be the first detailed characterisation of such an enzyme and investigation of its cellular function. The enzyme to be characterised is hepatic and it has been implicated in the regulation of ....Mammalian histidine kinase: its characterisation and role in hepatic cellular proliferation. Protein kinases regulate all aspects of cellular metabolism, but there is a class of protein kinase, histidine kinases, which exists in mammalian cells, about which remarkably little is understood. This project will be the first detailed characterisation of such an enzyme and investigation of its cellular function. The enzyme to be characterised is hepatic and it has been implicated in the regulation of DNA replication in regenerating liver. We shall obtain a detailed picture of the role of this histidine kinase in liver cell biology and an insight into the more general biological role of this class of enzyme.Read moreRead less
A global approach to structure, assembly and function of yeast mitochondrial ATP synthase. ATP synthase is responsible for the synthesis of the ubiquitous energy substance ATP in living cells. This multisubunit enzyme complex is a molecular rotatory motor whose mechanism relies on functional dynamic interactions of the component protein subunits of the complex. Using a combination of powerful and sophisticated molecular biology techniques the functional and dynamic contacts made by subunits wi ....A global approach to structure, assembly and function of yeast mitochondrial ATP synthase. ATP synthase is responsible for the synthesis of the ubiquitous energy substance ATP in living cells. This multisubunit enzyme complex is a molecular rotatory motor whose mechanism relies on functional dynamic interactions of the component protein subunits of the complex. Using a combination of powerful and sophisticated molecular biology techniques the functional and dynamic contacts made by subunits within the complex, or between ATP synthase and other enzyme complex involved in energy production (including other ATP synthase complexes) will be investigated. New and significant insights into one of the most fundamental and challenging enzymes of life will be obtained.Read moreRead less
The Structure Function and Biology of Serpins. The serpin family of proteins control protease activity, in a variety of biological systems, via a dramatic conformational change. We are 4 leaders in the serpin reseacrh field using an integrated approach of biochemistry, biophysics, molecular biology, cell biology, structural biology and bioinformatics to analyse every facet of serpin structure, function and biology. We will apply and develop novel technologies that will determine how these confor ....The Structure Function and Biology of Serpins. The serpin family of proteins control protease activity, in a variety of biological systems, via a dramatic conformational change. We are 4 leaders in the serpin reseacrh field using an integrated approach of biochemistry, biophysics, molecular biology, cell biology, structural biology and bioinformatics to analyse every facet of serpin structure, function and biology. We will apply and develop novel technologies that will determine how these conformational changes are achieved and how they are controlled. Our increased understanding of this inhibitor - enzyme interaction will have implications to other proteins which undergo conformational change and biotechnology.Read moreRead less
Structural and functional studies on prokaryote serpins. Proteins are the machines of life, many of which undergo complex movements to achieve function. The basic research described in this proposal will result in major outcomes in understanding how proteins fold, undergo complex changes in conformation, and misfold to dysfunctional states. As a result, the study will contribute fundamental knowledge that will underpin research in the fields of structural biology, protein design and protein fo ....Structural and functional studies on prokaryote serpins. Proteins are the machines of life, many of which undergo complex movements to achieve function. The basic research described in this proposal will result in major outcomes in understanding how proteins fold, undergo complex changes in conformation, and misfold to dysfunctional states. As a result, the study will contribute fundamental knowledge that will underpin research in the fields of structural biology, protein design and protein folding. Through providing insight into protein misfolding, the work will will contribute to our understanding of degenerative misfolding pathologies that affect the ageing population and thus targets the 'ageing well ageing productively' priority goal.Read moreRead less
Developing orthogonal synthetic signaling cascades. This project proposes a generic approach for the construction of molecular switches based on artificially autoinhibited proteases. The bottom-up design of protein-based signaling networks is a key goal of synthetic biology. Yet, this remains elusive due to our inability to tailor-make signal transducers and receptors that can be readily compiled into defined signaling networks. Using structure-guided design and directed protein evolution, a set ....Developing orthogonal synthetic signaling cascades. This project proposes a generic approach for the construction of molecular switches based on artificially autoinhibited proteases. The bottom-up design of protein-based signaling networks is a key goal of synthetic biology. Yet, this remains elusive due to our inability to tailor-make signal transducers and receptors that can be readily compiled into defined signaling networks. Using structure-guided design and directed protein evolution, a set of protease-based signal transducers and ligand activated allosteric receptors will be created. The developed components are intended to be used to construct artificial signaling networks in mammalian cells that are orthogonal to the endogenous signaling cascades.Read moreRead less
Functional Dissection of the Bacterial Replisome. This project aims to develop and use a suite of new single-molecule techniques to define how the bacterial replisome really works. The replisome is the machine that makes DNA in cells that are about to divide. Replisomes have many mechanistic challenges as they work to copy both strands of DNA at the same time. Many years of classic biochemical studies have worked out how many of these challenges are overcome. In recent years, the use of single-m ....Functional Dissection of the Bacterial Replisome. This project aims to develop and use a suite of new single-molecule techniques to define how the bacterial replisome really works. The replisome is the machine that makes DNA in cells that are about to divide. Replisomes have many mechanistic challenges as they work to copy both strands of DNA at the same time. Many years of classic biochemical studies have worked out how many of these challenges are overcome. In recent years, the use of single-molecule biophysical techniques has begun to challenge many aspects of the elegant textbook view of replisome function. This approach is expected to reveal how synthesis of the two DNA strands in different directions at the same time is coupled together and how timing mechanisms work.Read moreRead less