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.
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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
Protein degradation in mammals. One mechanism by which the regulation of protein turnover occurs is the balance between the activity of enzymes responsible for the ubiquitination and deubiquitination of target proteins. The majority of targets of this second family of enzymes are unknown. This project proposes a method for the identification of the targets of two specific mammalian deubiquitinating enzymes in order to understand their function and to begin to explore this new research field. ....Protein degradation in mammals. One mechanism by which the regulation of protein turnover occurs is the balance between the activity of enzymes responsible for the ubiquitination and deubiquitination of target proteins. The majority of targets of this second family of enzymes are unknown. This project proposes a method for the identification of the targets of two specific mammalian deubiquitinating enzymes in order to understand their function and to begin to explore this new research field. Knowledge about this new aspect of protein degradation could provide a powerful tool to test the effect of the stabilisation or removal of specific proteins in the cell and also to develop new technologies in protein production.Read moreRead less
Why is the photosynthetic CO2-fixing enzyme, Rubisco, so inefficient? Dissection of the catalytic chemistry by computational simulation and experimental testing. Fixation of CO2 by the enzyme Rubisco during photosynthesis produces organic compounds which feed all life. Despite this critical role, Rubisco catalyses its reaction sluggishly and, worse, discriminates poorly between CO2 and O2, leading to useless products. Our combined expertise equips us to analyse Rubisco's mechanism using quantum- ....Why is the photosynthetic CO2-fixing enzyme, Rubisco, so inefficient? Dissection of the catalytic chemistry by computational simulation and experimental testing. Fixation of CO2 by the enzyme Rubisco during photosynthesis produces organic compounds which feed all life. Despite this critical role, Rubisco catalyses its reaction sluggishly and, worse, discriminates poorly between CO2 and O2, leading to useless products. Our combined expertise equips us to analyse Rubisco's mechanism using quantum-chemical methods and then test predictions experimentally. We will capitalise on our previous successful studies of Rubisco by addressing emergent issues which are the keys to understanding catalytic efficiency and CO2/O2 selectivity: the roles of a carbamylated lysine; the way CO2 addition is rendered irreversible; and the spin inversion inherent in O2 addition.Read moreRead less