Targeting Fungal Phospholipid Metabolism For Antifungal Drug Discovery
Funder
National Health and Medical Research Council
Funding Amount
$828,557.00
Summary
Invasive fungal infections are a serious and escalating health problem. They cause severe disease with a high death rate and are very costly to the health system. New antifungal drugs with novel properties are needed now because there are problems with current drugs. This project aims to develop potent new antifungal drugs that are effective in many fungal diseases and are well-tolerated.
Engineering Subtype Selective Inhibitors Of Voltage-sensitive Sodium Channels
Funder
National Health and Medical Research Council
Funding Amount
$406,980.00
Summary
During efforts to find new inhibitors of voltage sensitive sodium channels (VSSCs), we have discovered two new families of mu-conotoxins from Australian Conus tulipa and C. striatus that inhibit neuronal and muscle forms of the tetrodotoxin-sensitive (TTX-S) sodium channel. From these and related analogues we have identified a number of selective and highly potent inhibitors of VSSCs, opening the possibility of producing the first subtype selective TTX-S inhibitors useful in diseases such as epi ....During efforts to find new inhibitors of voltage sensitive sodium channels (VSSCs), we have discovered two new families of mu-conotoxins from Australian Conus tulipa and C. striatus that inhibit neuronal and muscle forms of the tetrodotoxin-sensitive (TTX-S) sodium channel. From these and related analogues we have identified a number of selective and highly potent inhibitors of VSSCs, opening the possibility of producing the first subtype selective TTX-S inhibitors useful in diseases such as epilepsy and stroke. These analogues also showed high selectivity for TTX-S sodium channels over a TTX-resistant (TTX-R) subtype hPN3, a key channel involved in the transmission of neuropathic pain that we recently cloned from human dorsal root ganglia. Given that TTX-S and TTX-R sodium channels have the same overall structure but differ at a relatively small number of key positions likely to affect mu-conotoxin binding, we believe it is possible to reverse engineer mu-conotoxin pharmacology in favour of the TTX-R form. This project will engineer subtype specific inhibitors of sodium channels in nerves through an understanding of how and wheremu-conotoxin bind to the sodium channel. Our long-term goal is to produce sodium channel drug candidates using m-conotoxins as templates for the development of subtype selective inhibitors of TTX-S and TTX-R sodium channels. The results of this study are designed to maximise the potential of this class of peptides as leads to the development of a new classes of therapeutics for pain, epilepsy and stroke.Read moreRead less
Haemopoiesis is the process by which cells in the blood become committed to a specific cell type, mature and proliferate. The production of blood cells is a dynamic and constant process and if dysregulated will result in a number of different diseases and-or leukemias. Using a leukemic cell line we identified two genes, Hls5 and Hls7-Mlf1, involved in red blood cell maturation. In addition, both these genes have been implicated in cancer, Hls5 functions as a tumor suppressor and Mlf1 is associat ....Haemopoiesis is the process by which cells in the blood become committed to a specific cell type, mature and proliferate. The production of blood cells is a dynamic and constant process and if dysregulated will result in a number of different diseases and-or leukemias. Using a leukemic cell line we identified two genes, Hls5 and Hls7-Mlf1, involved in red blood cell maturation. In addition, both these genes have been implicated in cancer, Hls5 functions as a tumor suppressor and Mlf1 is associated with acute myeloid leukemia. Over-expression of either gene in immature red blood cells inhibited their development; Mlf1 had quite a profound affect on cell shape and size whereas Hls5 affected biochemical pathways with a decrease in haemoglobin production. We have identified binding partners of each of the molecules. Hls5 binds to FOG 1, a regulator of the red blood cell genes. In addition, Hls5 associates with Ubc9 and PIAS-1 - molecules involved in a novel form of gene regulation called sumoylation. Hls5 also regulates GATA-1 a key protein in red cell production. Wer have recently found that Mlf1 also regulates GATA-1. Importantly, we have demonstrated that Mlf1 binds DNA and other nuclear proteins and is able to affect gene transcription. This project will use cellular and biochemical assays as well as mouse models to elucidate the mechanisms by which these genes control the function of red blood cells.Read moreRead less
Dissecting The Divisome: Development Of Antibacterial Agents That Inhibit Bacterial Cytokinesis
Funder
National Health and Medical Research Council
Funding Amount
$504,097.00
Summary
Infectious diseases accounted for 25-30% of the estimated 54 million deaths worldwide in 1998. Unfortunately, the recent spread of antibiotic resistant bacteria from hospitals into the community has coincided with a marked downturn in the rate of development of new antibiotics. Thus, there is an urgent need to develop new antimicrobial agents. The aim of this project is to provide essential groundwork for the development of new antimicrobials that inhibit bacterial cell division.
IgA Mediated Activation Of FcalphaRI, An Fc Receptor And A Leukocyte Ig-like Receptor.
Funder
National Health and Medical Research Council
Funding Amount
$535,500.00
Summary
Our immune system exists to seek and destroy infections caused by bacteria and viruses (pathogens) that would grow in us. B cells in the immune system make antibody tags which attach to pathogens marking them for elimination. A special type of antibody is IgA. IgA occurs in two forms, the first is found at mucosal sites, these are membranous passages in the body, such as the lung, the gut and the genital tract. These communicate with the outside and are the major route of pathogen entry into the ....Our immune system exists to seek and destroy infections caused by bacteria and viruses (pathogens) that would grow in us. B cells in the immune system make antibody tags which attach to pathogens marking them for elimination. A special type of antibody is IgA. IgA occurs in two forms, the first is found at mucosal sites, these are membranous passages in the body, such as the lung, the gut and the genital tract. These communicate with the outside and are the major route of pathogen entry into the body. Here IgA forms a rather passive, but pathogen specific, sticky barrier to prevent microbial pathogens attaching to these large surfaces. In an everyday analogy this IgA behaves somewhat like fly-paper. This subdued response is appropriate as we are constantly exposed to micro-organisms living in our gut, or breathed into our lungs, and our immune system would make us ill if it aggressively attacked our innocuous microbial neighbours. The second type of IgA is found in the blood where it attaches to pathogens that have breached the body's barriers. These IgA tags are actively sought by white blood cells whose function is to protect the body from infection by recognising and engulfing the tagged pathogens and destroying them with killer molecules, including bleach. The IgA-Fc receptor is the sensor on the surface of white blood cells which seeks the IgA tags as they attach to pathogens. In order to survive in this hostile environment some of our pathogens, such as Staphylococcus, have their own strategies to make themselves invisible to the immune system. These strategies include cutting up the IgA tags or blocking the sensors for IgA. In this project we will study how IgA tags turn on white blood cells to destroy pathogens. We will also be looking at two Staphylococcal proteins which block up the sensor for IgA tags. Finally we are endeavouring to understand how it is the mucosal type IgA does not activate the white cells nearly as much as the IgA from the blood.Read moreRead less
Selectivity And Mode Of Action Of Rho-conopeptide TIA: A Novel Inhibitor Of Alpha1-adrenoceptors.
Funder
National Health and Medical Research Council
Funding Amount
$399,300.00
Summary
A major obstacle to the development of safer and more effective treatments for cardivascular diseases and benign prostatic hyperplasia is the inability to find small molecules with sufficient specificity to be safe and effective. The applicant team brings together a unique set of complementary research interests and skills in using conotoxins to define, at the molecular level, how rho-conotoxins act at the alpha1-adrenoceptor, a major drug target for cardiovascualr and related diseases. Rho-cono ....A major obstacle to the development of safer and more effective treatments for cardivascular diseases and benign prostatic hyperplasia is the inability to find small molecules with sufficient specificity to be safe and effective. The applicant team brings together a unique set of complementary research interests and skills in using conotoxins to define, at the molecular level, how rho-conotoxins act at the alpha1-adrenoceptor, a major drug target for cardiovascualr and related diseases. Rho-conotoxins are novel peptide inhibitors of the alpha1-adrenoceptor that appear to act at an undescribed allosteric site. This Project will use rho-conotoxins and analogues to characterise structurally and functionally how and where this class of conopepides act. The structure activity relationship for rho-conotoxins will be established to guide the development of subtype specific inhibitors. Pairwise interactins between the alpha1-adrenoceptorand TIA will be used to dock TIA onto a homolgy model of the alpha1-adrenoceptor. The long-term goal of the project is to develop new and safer treatments for cardiovascular and related disorders.Read moreRead less
Fc Alpha RI: Ligand Interaction And Membrane Organisation.
Funder
National Health and Medical Research Council
Funding Amount
$497,640.00
Summary
Antibodies tag invading viruses or bacteria thus marking them as foreign and targeting them for destruction by the immune system. In man the most prevelant antibody is IgA and this antibody provides protection from infecton in the blood and in the fluids at the surface of the lungs, gut and urinogenital tract. Once tagged by antibody the invading bacteria or antigen can be recogniseed white blood cells. These workhorses of the immune system use special molecules called Fc receptors on their surf ....Antibodies tag invading viruses or bacteria thus marking them as foreign and targeting them for destruction by the immune system. In man the most prevelant antibody is IgA and this antibody provides protection from infecton in the blood and in the fluids at the surface of the lungs, gut and urinogenital tract. Once tagged by antibody the invading bacteria or antigen can be recogniseed white blood cells. These workhorses of the immune system use special molecules called Fc receptors on their surface to recognise antibody tags. The receptor for IgA tags is called the Fc alpha receptor. This receptor is essential for the normal IgA-mediated protection against infection. However in a common kidney disease IgA tags accumulate in the glomerulus of the kidney stimulating white blood cells to attack and damage the kidney. This study will explain how the Fc alpha receptor recognises IgA antibody tags. It will investigate how the presentation of different forms of the receptor and different types of IgA antibody tags contributes to immunity to infection. For example one form of the receptor has a fat molecule joined to its end. We believe this may affect where the Fc alpha recptor goes to in the white blood cell membrane and whether it can activate the white blood cell to fight the invading microorganism.Read moreRead less
Structure, Function And Regulation Of Human Cytosolic Sulfotransferases
Funder
National Health and Medical Research Council
Funding Amount
$265,500.00
Summary
The sulfotransferase family of enzymes serve an important role in the metabolism of drugs and foreign chemicals. They also metabolise a range of chemicals that are normally present in the body such as hormones and substances that are involved in brain function (neurotransmitters). Observations from clinical studies suggest that differences in sulfotransferases activities may be a causal factor in the incidence of certain types of cancer and neurodegenerative diseases. Recent advances in understa ....The sulfotransferase family of enzymes serve an important role in the metabolism of drugs and foreign chemicals. They also metabolise a range of chemicals that are normally present in the body such as hormones and substances that are involved in brain function (neurotransmitters). Observations from clinical studies suggest that differences in sulfotransferases activities may be a causal factor in the incidence of certain types of cancer and neurodegenerative diseases. Recent advances in understanding the molecular biology of these enzymes have shown us that multiple forms of sulfotransferase existed within the body. In this area my laboratory has been at the forefront of the cloning and characterisation of these enzymes. Indeed, we were the first laboratory to clone the major human sulfotransferase (SULT1A3) responsible for the metabolism of brain neurotransmitters. We have also used new technology to determine the shape of this important enzyme. At the time of writing my laboratory has characterised a total seven human sulfotransferases but unlike SULT1A3, our knowledge of the functional significance of the other six sulfotransferase is poorly understood. Further, our knowledge of what regulates the amount of sulfotransferase in different tissues is practically nonexistent. The thrust of this project is to extend our studies on the physiological function of these enzymes and also through the use of molecular biology techniques understand what controls the level of their expression in different human tissues. This knowledge will provide a basis for understanding the role of sulfotransferases play in drug and chemical metabolism. It will also aid our understanding of their role in hormone and neurotransmitter metabolism and help determine whether they are involved in such diseases as cancer and neurodegenerative diseases.Read moreRead less
Developing Novel Selective Glycine Receptor Potentiators As A Means To Control Pain.
Funder
National Health and Medical Research Council
Funding Amount
$552,647.00
Summary
It has been estimated that >3M Australians suffer from pain at a cost to the economy of >$34B, with chronic pain (persisting beyond 1-6 mths) accounting for ~half this burden. There is an urgent and compelling social and economic case for the development of safer and more effective pain therapeutics. This project takes inspiration from a new class of Australian marine natural products that selectively regulate a key pain pathway, and will optimize and develop these as a new class of pain d ....It has been estimated that >3M Australians suffer from pain at a cost to the economy of >$34B, with chronic pain (persisting beyond 1-6 mths) accounting for ~half this burden. There is an urgent and compelling social and economic case for the development of safer and more effective pain therapeutics. This project takes inspiration from a new class of Australian marine natural products that selectively regulate a key pain pathway, and will optimize and develop these as a new class of pain drug.Read moreRead less
The Structural Basis Of Cytokine Signalling Inhibition
Funder
National Health and Medical Research Council
Funding Amount
$239,473.00
Summary
Cell-cell communcation is vital for the correct functioning of the body. Cells need to be told the correct time to divide, to produce certain enzymes or chemicals, to migrate and also when to apoptose, or die. Cells receive these signals through the binding of small soluble proteins called cytokines. Cytokines bind to specialized receptors on the surface of the cell and initiate an intracellular signaling cascade that passes the correct message to the nucleus. It is important that cells react to ....Cell-cell communcation is vital for the correct functioning of the body. Cells need to be told the correct time to divide, to produce certain enzymes or chemicals, to migrate and also when to apoptose, or die. Cells receive these signals through the binding of small soluble proteins called cytokines. Cytokines bind to specialized receptors on the surface of the cell and initiate an intracellular signaling cascade that passes the correct message to the nucleus. It is important that cells react to these protein messengers however it is just as vital that they don't overreact. Many human diseases, especially inflammatory diseases such as rheumatoid arthritis and type II diabetes, are due to aberrant cytokine signaling. To ensure this doesn't occur, cells have evolved a mechanism to quickly switch off the signaling cascade after it has started. This mechanism involves an entire family of proteins, the Suppressors of Cytokine Signalling (SOCS) family. These proteins can act via two distinct mechanisms. The first is to directly block the JAK-STAT proteins, proteins that initiate the intracellular part of the signaling cascade. The second mechanism has been less well studied, it involves the SOCS proteins upregulating the degradation of signaling intermediates. The SOCS proteins can do this through the action of a 40 residue domain called the SOCS box. The SOCS box directs proteins bound to other domains of the SOCS proteins to be degraded by interacting with a complex called an E3 ubiquitin ligase. This project involves determining the three-dimensional atomic structure of the SOCS-E3 ligase interaction and investigating biophysical aspects of the interaction. This information will lead to a fuller understanding of the mechanism of signaling inhibition and will provide information crucial to the design of SOCS inhibitors. Such inhibitors would be therapeutically important in the treatment of a number of human diseases such as cancer, arthritis and type II diabetes.Read moreRead less