Genetics And Biochemistry Of Biosynthesis Of The Cell Wall Of Mycobacteria
Funder
National Health and Medical Research Council
Funding Amount
$260,831.00
Summary
Mycobacteria commolnly cause human disease. The major killer in the group is Mycobacterium tuberculosis which annually causes millions of deaths from tuberculosis (TB) worldwide. Another pathogen from this group is Mycobacterium avium which often infects immunosuppressed people such as those with advanced HIV-AIDS. Mycobacteria have evolved a specialised wall that surrounds their cells which protects them from chemical attack from antibiotics and helps them to establish infections. The major ant ....Mycobacteria commolnly cause human disease. The major killer in the group is Mycobacterium tuberculosis which annually causes millions of deaths from tuberculosis (TB) worldwide. Another pathogen from this group is Mycobacterium avium which often infects immunosuppressed people such as those with advanced HIV-AIDS. Mycobacteria have evolved a specialised wall that surrounds their cells which protects them from chemical attack from antibiotics and helps them to establish infections. The major antibiotic used for TB stops cells from synthesising the protective layer thereby making them very vulnerable to human immune defences. Unfortunately, resistance to this antibiotic is common and new antibiotics are needed to treat mycobacterial infections. We are studying how mycobacteria make the cell wall and are looking for key steps where new drugs might be able to inhibit the process. Our approach is to inactivate genes in the mycobacteria that make the enzymes which control cell wall synthesis. The gene inactivation results in crippled mycobacteria that are unable to make proper cell walls. We analyse the cell wall changes that gene inactivation cause studying the chemical composition of the cell. This helps to identify the steps in cell wall biosynthesis and each step becomes a potential target for new drugs. Each of the weaken mycobacteria can be tested to see how well they can resist antibiotics and to see if they can survive host defences. In this way we can identify which components of the cell wall are critical for them to establish infections and resist antibiotic treatments. Enzymes that participate in the synthesis of such components are prime targets for us to concentrate on to design new antibiotics.Read moreRead less
Novel TB Drug Candidates Via The Inhibition Of Lipid I Biosynthesis
Funder
National Health and Medical Research Council
Funding Amount
$780,743.00
Summary
Tuberculosis (TB) is an enormous global health problem with a continuing impact in Australia. TB is now the leading killer of any infectious disease (1.8 million people per year) and the rapid emergence of drug resistant TB infections threatens to prevent efforts to control the disease. This project seeks to develop novel TB drug candidates that operate by preventing the construction of the cell wall by the bacterial agent that causes the disease.
Apoptosis Amongst Specific And Bystander T Cells In Chronic Bacterial Infection
Funder
National Health and Medical Research Council
Funding Amount
$317,545.00
Summary
When an infection occurs the immune cells (lymphocytes) proliferate in order to initiate and expand the immune response. If the body had no mechanisms to limit proliferation, the numbers of cells would soon overwhelm the body. Working with simple protein antigens rather than infection, other workers have found that once T lymphocytes have been activated and the immune response triggered, they soon undergo a process of self destruction called apoptosis. However, during infection, if the limits to ....When an infection occurs the immune cells (lymphocytes) proliferate in order to initiate and expand the immune response. If the body had no mechanisms to limit proliferation, the numbers of cells would soon overwhelm the body. Working with simple protein antigens rather than infection, other workers have found that once T lymphocytes have been activated and the immune response triggered, they soon undergo a process of self destruction called apoptosis. However, during infection, if the limits to lymphocyte proliferation are imposed before the infecting bacterium is eliminated, full expression of immunity does not occur and chronic infection may result. We believe that this contributes to the chronicity of such infections as tuberculosis and leprosy. We also suspect that, during infection, not only protective T lymphocytes proliferate, but also nonspecific bystander cells. This exaggerates the problem of lymphocyte proliferation and adds to immunopathology (immune damage). We have established an animal model of chronic bacterial infection in order to study how apoptosis is induced in T lymphocytes and how its adverse effects may be overcome. We hypothesize that apoptosis may be induced by one or more of a number of mechanisms, and that they may differ for the specific protective cells and the bystander cells. Once we understand the mechanisms apoptosis of specific lymphocytes may be prevented without harming the body. This has the potential to open new areas of immunotherapy (manipulating the immune response) of these diseases.Read moreRead less
Discovery Of New Tuberculosis Drug Leads Targeting Cell Wall Biosynthesis
Funder
National Health and Medical Research Council
Funding Amount
$714,816.00
Summary
There is a desperate need for the development of new therapies for the treatment of TB due to widespread resistance of Mycobacterium tuberculosis, the causative agent of TB, to current therapies. The overall goal of this research project is to identify new TB drug leads through the development of structural analogues of bacterially-derived natural products called the sansanmycins that inhibit cell wall synthesis in Mycobacterium tuberculosis.
Identifying Drug Targets In Microbial Pathogens Using Metabolomics
Funder
National Health and Medical Research Council
Funding Amount
$763,409.00
Summary
Infectious diseases such as malaria, leishmaniasis and tuberculosis cause enormous morbidity and mortality worldwide. This proposal will utilize advanced analytical and genetic approaches to study the metabolism of the respective protozoan and bacteria agents as well as the associated host responses. These approaches will be used to develop novel therapeutic approaches and new analytical tools that can be applied to other infectious diseases