Structural Analysis Of Poxvirus Immature Particles And Spheroids
Funder
National Health and Medical Research Council
Funding Amount
$387,489.00
Summary
Despite the eradication of smallpox by vaccination, poxviruses remain a threat to public health because of bioterrorist scares from kept variola stocks and because of the possible emergence of other poxvirus pathogens from the extensive animal reservoir. The structural analysis of the assembly of poxvirus will not only improve our knowledge of fundamental processes, highly conserved in DNA viruses, but could also provide valuable targets for the rational design of antiviral drugs.
RECOMBINANT MALARIAL PYRIMIDINE ENZYMES AS DRUG TARGETS
Funder
National Health and Medical Research Council
Funding Amount
$229,750.00
Summary
Malarial parasites have now developed resistance to most of the available drugs and there is an urgent need for drugs with new mechanisms of action. Institutions collaborating on the Malarial Genome Project have sequenced the majority of DNA in the 14 chromosomes. The nucleotide sequence available on the internet contains thousands of open reading frames (ORFs) which encode proteins essential for survival of the parasite. Many of these proteins are enzymes which are suitable targets for drug dev ....Malarial parasites have now developed resistance to most of the available drugs and there is an urgent need for drugs with new mechanisms of action. Institutions collaborating on the Malarial Genome Project have sequenced the majority of DNA in the 14 chromosomes. The nucleotide sequence available on the internet contains thousands of open reading frames (ORFs) which encode proteins essential for survival of the parasite. Many of these proteins are enzymes which are suitable targets for drug development. A knowledge of the molecular architecture of the active site of such enzymes provides a template for drug design. The malarial parasite, Plasmodium falciparum, can only synthesise pyrimidine nucleotides for DNA via the de novo pyrimidine pathway. We have cloned the genes encoding three of the enzymes of the de novo pathway using sequence information from the Malarial Genome Project. Dihydroorotase, orotate phosphoribosyltransferase, and OMP decarboxylase, catalyse reactions 3, 5 and 6 of the pathway. We have expressed these enzymes in the bacterium Escherichia coli enabling large-scale production of these drug targets. We propose to characterise the catalytic and inhibitory properties of these enzymes, and grow protein crystals for determination of atomic structures by x-ray diffraction. The structures will provide templates for rational design of new antimalarial drugs. In a second approach for develoment of new drugs, the 3 malarial enzymes will be screened against chemical libraries for inhibition of catalytic activity. The initial screen will utilise a high throughput Biacore 3000 instrument which detects strong interactions between a target enzyme and candidate inhibitors. A thorough knowledge of the catalytic mechanisms, the three-dimensional structures and novel first generation inhibitors of these 3 malarial target enzymes, will provide a strong basis for development of new antimalarial drugs.Read moreRead less
The Future Of HIV Care - Long Term Remission And Eliminating Co-morbidities
Funder
National Health and Medical Research Council
Funding Amount
$577,189.00
Summary
Despite the great successes in antiretroviral therapy (ART) in reducing HIV-associated mortality, treatment is life long and there is no cure. The major barrier to a cure for HIV is the persistence of long lived latently infected cells on ART. Over the next five years I will discover, develop, optimise and evaluate novel interventions to eliminate latently infected cells, long lived infected cells in the liver and enhance HIV-specific immunity through immunotherapy.
We plan to continue our work that to date is consistent with the idea that excessive induction of the enzyme iNOS, and thus production of nitric oxide in key locations, is a central event in how falciparum malaria kills people who become infected with this parasite. This will largely be based on detecting iNOS and nitrotyrosine in tissues from autopsies collected as part of a malaria research programme conducted in Malawi. Laboratory experiments will also be performed. In particular, there is a ....We plan to continue our work that to date is consistent with the idea that excessive induction of the enzyme iNOS, and thus production of nitric oxide in key locations, is a central event in how falciparum malaria kills people who become infected with this parasite. This will largely be based on detecting iNOS and nitrotyrosine in tissues from autopsies collected as part of a malaria research programme conducted in Malawi. Laboratory experiments will also be performed. In particular, there is a body of evidence that suggests the following interactions between inflammatory cytokines and salicylate, with important practical ramifications, in children. 1. Salicylate toxicity, like the acute multi-organ form of childhood malaria it mimics, is probably caused by excess systemic iNOS induction. This plausibly includes the metabolic acidosis, hypoglycaemia, seizures, coma and cerebral oedema seen in both conditions. Both are thus logically susceptible to treatment with specific iNOS inhibitors. 2. The same picture would arise in children when smaller doses of salicylate synergise with IFN-g, IL-1b, and perhaps other cytokines induced by malaria as well as by viruses. This gives the first proposed explanation for Reye's syndrome, defining the circumstances in which it occurs, and predicting a rationale for its treatment. Through the parallels seen in different age groups in malaria and aspirin toxicity, it also rationalises the difference in childhood vs adult malaria syndromes. 3. The overall severity and mortality of childhood malaria in East Africa may be worsened, through this cytokine-salicylate synergy, by home treatment with aspirin when children first become ill. 4. A relative absence of salicylate intake by children in various malarial Pacific Islands may contribute to falciparum malaria being a less severe disease there than in East Africa.Read moreRead less
A Functional And Structural Approach To Understanding Leptospiral Host-pathogen Interactions
Funder
National Health and Medical Research Council
Funding Amount
$504,097.00
Summary
Leptospirosis is a zoonosis of worldwide distribution caused by infection with pathogenic Leptospira. Infection occurs due to contact with water contaminated by urine of domestic animals. It occurs infrequently in Australia, but recent local surveillance data indicate hospitalisation rate of 56% with an average duration of 5.3 days. Through the combined approach of structural biology and functional microbiology we hope to understand how leptospira interacts with the human host.
Translating Research Into HIV-related Health Outcomes In The Developing World
Funder
National Health and Medical Research Council
Funding Amount
$714,745.00
Summary
Professor Crowe's research addresses important health issues for HIV infected people living in resource limited countries. Her team validates low cost point of care tests to monitor HIV infection, including a test she co-developed to determine when to start anti-HIV treatment, and investigates how these low cost tests can improve clinical care of people with HIV and TB. In addition she will determine how changes in the immune system increase the risk of heart attacks in young HIV patients.
Structural Characterization Of Novel AB5 Cytotoxin - SubAB
Funder
National Health and Medical Research Council
Funding Amount
$445,011.00
Summary
AB5 toxins are virulence factors from a range of pathogenic bacteria, including Shiga toxigenic E. coli (STEC), S. dysenteriae, V. cholerae, and B. pertussis. AB5 toxins comprise a catalytic A subunit that disrupts distinct essential cellular processes within the cell and a receptor binding, pentameric B subunit that enables the toxin to target certain cell types. We are structural characterizing a novel AB5 toxin that targets an essential component of the cellular machinery.
Randomised Trial To Determine The Safety And Efficacy Of Early Vs Deferred Treatment Of HIV
Funder
National Health and Medical Research Council
Funding Amount
$1,070,331.00
Summary
Treatments for HIV represent a miraculous achievement of medical research. Global use of antiretroviral drugs has prevented substantial morbidity and mortality. However, it is unclear if these drugs should be used in people who are HIV positive with early HIV disease but no clinical symptoms. The START trial will result in a precise estimate of the risk-benefit for earlier versus later use of these treatments. It will immediately affect treatment guidelines around the world and inform future res ....Treatments for HIV represent a miraculous achievement of medical research. Global use of antiretroviral drugs has prevented substantial morbidity and mortality. However, it is unclear if these drugs should be used in people who are HIV positive with early HIV disease but no clinical symptoms. The START trial will result in a precise estimate of the risk-benefit for earlier versus later use of these treatments. It will immediately affect treatment guidelines around the world and inform future research for many years to come.Read moreRead less
Inhibition Of Histidine Kinase Signal Sensing: A Novel Paradigm For Antimicrobial Development
Funder
National Health and Medical Research Council
Funding Amount
$464,144.00
Summary
Staphylococcus aureus (Golden staph) has been termed a superbug because of its remarkable ability to acquire resistance to virtually all antibiotics. Until recently, Golden Staph infections were almost always acquired in hospitals, but the increasing incidence of community-acquired S. aureus infections has rendered it a major public health threat in Australia. The aim of this research is to develop antimicrobial agents to combat antibiotic-resistant strains of Staphylococcus aureus.