Charles Sturt University
Charles Sturt University

Molecular Biology

Molecular Biology

Continuing genotypic and other analysis of Mucor amphibiorum fungal isolates from diseased platypuses and amphibians

We have compared Mucor isolates from diseased Tasmanian platypuses and mainland toads and frogs using ISSR PCR and also sequencing of the conserved ITS regions. 

Top of page

Surface tegument development of Fasciola hepatica under different culture conditions in vitro

Fasciolosis, caused by the parasite Fasciola, is a zoonotic disease in production animals and humans, causing significant economic losses (>US $3 billion p.a.) to the global agricultural sector. Over 500 million animals are infected with Fasciola sp. in the world, and up to 40 million sheep and 6 million cattle graze on fluke endemic pastures in Australia, causing economic loss within Australia of $90 million p.a. Resistance to the main anthelmintic used to treat this parasitic infection, triclabendazole, has been reported in Australia and is now widespread in Europe. At present, there is no commercial vaccine for controlling this disease; we are interested in developing a vaccine by targeting surface proteins expressed on the surface sheath(tegument) of the parasite since we know that immunity to Fasciola in sheep involves an antibody-mediated killing mechanism directed to these surface tegument proteins. However, the parasite is able to evade the host's immune system by varying the tegumental proteins as it develops from a juvenile to adult parasite within the host but the surface proteins expressed by the parasite have not yet been well defined.

  • The first aim of this project is to culture Fasciola hepatica parasites from juvenile stages through to young adults in the presence of various mediums to determine the effects they have on the growth and development of the parasite.
  • The second aim is to examine, using proteomics and microscopy techniques, tegument changes during the development process. The student will receive training in tissue culture, proteomics, cell biology, bioinformatics and Parasitology.

Supervisor

     

Top of page

Identification of Staphylococcus aureus biomarkers in milk of Dairy Cows

Milk from cows with mastitis (S. aureus infections) is unsafe for human consumption and detection of an infection is critical to food safety. At present, bacterial culture is performed on milk products but these tests can take days and often results are returned as negative or inconclusive. These poor results may be due to irregular distribution of S. aureus in the cow's udder or contamination of other bacteria. For successful treatment of S. aureus, infected cows need to be diagnosed quickly, and treated to minimise spread of the pathogen to the herd.

  • The first aim of this project is to screen milk samples from control and infected cows for somatic cell count irregularities.
  • The second aim is to compare, using 1D and 2D electrophoretic techniques, protein profiles of each of these samples. Novel protein markers observed in infected milk will be characterised using MALDI-TOF MS/MS and bioinformatics. With time permitting, antisera will be generated to biomarkers of interest and used for ELISA and western blot analysis to potentially diagnose mastitis. The student will receive training in microbiology, proteomics, cell biology and bioinformatics.

Supervisor

Top of page

Diversity among cryptochrome genes in chicken and their association with magnetic orientation behaviour

The discovery of the magnetic sense in migratory birds and subsequent research has identified the Earth's magnetic field as the major cue in the orientation of many organisms ranging from tiny bacteria to many invertebrates and vertebrates. A recent study on chickens, a common laboratory animal, has shown that they also possess a magnetic sense. However, the mechanism that chickens, and indeed other birds, use for detecting the magnetic field is largely unknown. Cryptochromes are a family of proteins found in many animals, birds and plants where they play a role in mediating and regulating circadian rhythms and other responses to light. Recently, it was demonstrated that two cryptochrome genes are expressed in the retinas of European robins and are potential involved in detecting the magnetic field. The genetic analysis of the cryptochromes of these two birds suggests that cryptochrome eCry1b is the possible transducer for the avian magnetic sense. However, while these results appear promising too few birds have yet been screened for retinal cryptochromes and their potential association with the magnetic sense. This project combines analysis of orientation behaviour of chickens in a laboratory test with cloning and sequencing cryptochrome genes to investigate if any genetic variability exists between individuals able or not able to respond to magnetic cues.

Supervisor 

Top of page

Use of faecal DNA as a Tool for Diagnosing Plant Poisoning in Livestock

Plant poisonings cost the Australian livestock industry more than $100 million each year through loss of animals, losses in production, and associated veterinary costs (Dowling & McKenzie 1993). Part of the difficulty in treating (if possible) affected animals is the problem of ascertaining whether the animal(s) has in fact consumed a poisonous plant. In many instances, the plant may no longer be present in the immediate area, simply because the animal has consumed it. Faecal DNA has been successfully used to determine the presence of specific (desirable) plants in the diets of grazing sheep and kangaroos (current research, Krebs et al). The aim of this research is to establish if consumption of poisonous plants can be determined using faecal DNA and if level of consumption impacts on the success of the technique.

There are a large number of toxic plants that grazing animals have access to, but in most instances these will be avoided by livestock. For this initial study, only two plants will be selected:

  • Echium plantagineum (Patterson's Curse), contains pyrrolizidine alkaloids. Toxic to all grazing animals, but considered highly toxic to horses in particular.
  • Heliotropium europaeum (Common heliotrope), contains pyrrolizidine alkaloids, and is responsible for poisonings in sheep, cattle and horses

The project will involve the following:

  • An animal based feeding study (sheep & horses) using clinically non-toxic levels of the two poisonous plants to confirm consumption via faecal DNA analysis over a set time course.
  • Utilisation of molecular biology techniques to determine the probability, reliability & specificity of detecting the specific plant DNA in small faecal samples.

Supervisor

  • Dr Gaye Krebs
  • Partner Investigator: Dr Kevin Ho (Chemistry Centre of Western Australia)

Top of page

 

Livestock Semen Assessment: A Comparison of Traditional and New Methodologies

Using submitted extended boar semen, the student will compare routine traditional semen assessment methods with new/evolving methods, as below.

Traditional methods New methods/technologies
Motility (BF microscopy)
% Live/dead
% Normal sperm
Sperm motility (CASA)
Ubiquitin (proteomics)
SCSA* (flow cytometery)

* Sperm chromatin structure assay

As part of this project, the student will learn a number of research techniques including Lab GLP and applications of biostatistics. In addition, each test employed must be validated. The student will be expected to undertake a literature review of semen evaluation methods.

Supervisor

Top of page