Biosynthesis of nonribosomal peptide toxins in cyanobacteria: A functional characterisation of microcystin synthetase. Microcystins are potent toxins and tumour promoters produced by cyanobacteria associated with blue-green algal blooms. This non-ribosomal peptide is produced by microcystin synthetase, a unique enzyme complex comprised of peptide synthetases, polyketide synthases, and integrated accessory enzymes. We have identified and characterised the extensive gene cluster encoding this enzy ....Biosynthesis of nonribosomal peptide toxins in cyanobacteria: A functional characterisation of microcystin synthetase. Microcystins are potent toxins and tumour promoters produced by cyanobacteria associated with blue-green algal blooms. This non-ribosomal peptide is produced by microcystin synthetase, a unique enzyme complex comprised of peptide synthetases, polyketide synthases, and integrated accessory enzymes. We have identified and characterised the extensive gene cluster encoding this enzyme. This project describes the biochemical characterisation of specific enzyme activities within microcystin synthetase and how they determine the final structure and toxicity of the many forms of microcystin. Interactions between this enzyme complex and its substrate amino acids will provide information for the genetic engineering of this and similar natural products.Read moreRead less
Preventing The Evolution Of Transmissible Nitroimidazole Resistance In Mycobacterium Tuberculosis
Funder
National Health and Medical Research Council
Funding Amount
$664,463.00
Summary
Tuberculosis kills more people than any other infectious disease. Unfortunately, the drugs available to us to treat TB are losing their efficacy due to the evolution of drug resistance. A new class of drugs, nitroimidazoles, has been developed, but there is a risk that the bacterium that causes TB will develop resistance to these compounds too. We will identify resistance mutations before they occur in the wild, to help identify them and find new compounds for which resistance cannot develop.
DsbA Foldases From Multidrug Resistant Pathogens As Targets For New Antimicrobials
Funder
National Health and Medical Research Council
Funding Amount
$743,401.00
Summary
Bacteria that cause common human infections, such as cystitis and diarrhoea, are now resistant to many antibiotics. If no action is taken, by 2050 antibiotic resistant infections will kill more people each year than cancer. This project aims to address this global public health crisis by characterising promising new bacterial targets and inhibitors designed to disarm multidrug resistant pathogens. Longer term this work could provide new infection therapies that are urgently needed.
Broad Spectrum Inhibition Of An Enzyme Antibiotic Target
Funder
National Health and Medical Research Council
Funding Amount
$321,534.00
Summary
There is a well-documented need to replenish the antibiotic pipeline with new products to combat the rise of drug resistant bacteria. In this project, the enzyme dihydrodipicolinate synthase (DHDPS) is targetted which is essential to bacterial viability. A number of independent but synergistic drug discovery approaches are investigated to develop and test DHDPS inhibitors in the pursuit of a novel class of antibiotics.
The Molecular Mechanism Of Sphingosine Kinase Activation
Funder
National Health and Medical Research Council
Funding Amount
$442,500.00
Summary
Many cell processes like growth, death and differentiation are controlled by hormones and other molecules that interact with receptors on the outside of the cell. When this type of molecule binds to a receptor, it often triggers the production of signaling molecules inside the cell that initiate a change in the cells behaviour. The lipid molecule, sphingosine phosphate has been identified as such a signaling molecule that appears to be involved in the regulation of a diverse array of important m ....Many cell processes like growth, death and differentiation are controlled by hormones and other molecules that interact with receptors on the outside of the cell. When this type of molecule binds to a receptor, it often triggers the production of signaling molecules inside the cell that initiate a change in the cells behaviour. The lipid molecule, sphingosine phosphate has been identified as such a signaling molecule that appears to be involved in the regulation of a diverse array of important mammalian cellular processes. Recent studies have found that sphingosine phosphate is involved in the inflammation of cells, and if its production can be blocked, inflammation is not seen. Therefore, this provides a potential target for therapeutic intervention in the inflammation process. However, the manner by which cells regulate sphingosine phosphate levels is not well known. It is known that sphingosine phosphate is produced by the enzyme sphingosine kinase, and strong evidence suggests that changes in this enzyme's activity in the cell regulate sphingosine phosphate levels. However, how the cell changes the levels of sphingosine kinase activity is completely unknown. This study will investigate this problem with the view that understanding this process will allow the development of new drugs to block increases in sphingosine kinase activity, preventing increases in sphingosine phosphate levels, and it turn, preventing cellular inflammation.Read moreRead less
Biochemical Investigation Of Ubiquitination By The Fanconi Anaemia Pathway
Funder
National Health and Medical Research Council
Funding Amount
$603,447.00
Summary
Fanconi anaemia is an inherited disorder with greatly elevated risk of leukaemia and cancers. The causal genes are ‘tumour suppressors’ that protect us from cancer by a complex function in repair of damage to our DNA. This study aims to understand how this DNA repair function protects us from cancer, and may influence some forms of new forms of cancer treatment.
Redox Control Of The Immune Regulatory Protein, Indoleamine 2,3-dioxygenase
Funder
National Health and Medical Research Council
Funding Amount
$576,538.00
Summary
An enzyme called indoleamine 2,3-dioxygenase is important for controlling the immune system during normal and disease conditions including pregnancy, cancer, inflammation and infectious disease. Despite its importance little is known about how this enzyme is controlled. This project will provide important new insights into how this enzyme is regulated. Such fundamental scientific information can discover new ways in which to alter the enzyme's activity in order to modulate immune responses.
An Integrated Approach To Combat Antibiotic Resistance
Funder
National Health and Medical Research Council
Funding Amount
$389,120.00
Summary
The development of antibiotics such as penicillin was hailed as one of the great breakthroughs in medicine. However, an increasing number of pathogens have acquired resistance to these drugs. One of the most common resistance mechanisms employed by these pathogens is the use of metal dependent enzymes that promote the degradation of antibiotics. To date, no clinically useful inhibitors for these enzymes are available. In this project, we aim to develop such inhibitors as therapeutic drug leads.