Poster Presentations

Session Title: Global Climate Change
Presentation Date: Thursday, August 21, 2008
Poster Board Number: 0358

DEVELOPMENT OF A METHOD FOR ISOLATING VIRUSES OF RUMINAL METHANOGENS

D. Ouwerkerk, E. Constantinoiu, A. Klieve
Department of Primary Industries and Fisheries, Animal Science, Moorooka, Australia

Background and aims: Enteric methane generation in ruminants is a significant source of greenhouse gas emissions. While bacteriophages have been used to lower populations of bacteria such as Escherichia coli O157:H7 in ruminants, no viruses of rumen methanogens have been isolated. The objective of this study was to develop methodologies to isolate lytic viruses of ruminal methanogenic archaea.
Methods: A modification of the Hungate roll-tube technique has been developed. The roll-tube technique allows for pressurisation of the tube with H₂ gas which is necessary for the growth of the methanogens. Methanobrevibacter sp. YE286 was inoculated into 50 mL BY+ broth medium and harvested in early log growth phase by centrifugation to concentrate the cells. These cells were inoculated into the modified roll tube, pressurised to 30 psi with H₂ and incubated at 39 ^oC. Standard techniques for the concentration and isolation of bacteriophage populations from a variety of sources including abattoir wash, sewage and rumen fluid will be used for isolation of methanogen viruses.
Results: A thick lawn of methanogenic bacteria has been successfully grown in the modified roll tubes and source material obtained for concentration of viruses for screening against Methanobrevibacter sp. YE286.
Conclusion: The establishment of a visible lawn of Methanobrevibacter sp YE286 using a modified roll-tube technique will greatly enhance efforts to isolate viruses that may reduce methanogen populations and methane emissions.