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The Interaction Between PauA and Plasminogen which Promotes Intramammary Infection and Mastitis by Streptococcus.uberis. - OD1712

Bovine mastitis is the most common infectious disease of dairy cattle and costs the UK dairy industry around £ 170 M per year. Its control and treatment in the UK relies on the use of around 12 million doses of therapeutic and prophylactic antibiotic per year.

Streptococcus uberis is responsible for around 30% of all cases of mastitis in the UK. Infection by this bacterium is not prevented by recommended husbandry procedures and new strategies are needed to limit economic loss, reduce the use of antibiotics, improve food quality and improve the health and welfare of dairy cattle.

Vaccines aimed at preventing the growth of this bacterium in vivo have been shown to have the potential to control infection. All strains of S. uberis require at least eight amino acids for growth. These are not freely available in vivo but may be acquired from host proteins following their degradation by plasmin. S. uberis activates bovine plasminogen to plasn?iin through the action of the protein PauX The activation of bovine plasminogen by PauA is dependent on specific regions of both molecules; these have not been identified. This project aims to address this issue.

By determining the sites of interaction of the two proteins it will be possible to identify regions of PauA which may be used in the formulation of effective vaccines and will identify regions of bovine plasminogen which if altered would prevent its activation by PauX Such information may permit the identification of animals in which this sequence varies, these would be predicted to be more resistant to infection with S. uberis and could be used to breed selectively for resistance to mastitis by this bacterium.

Both strategies should lead to reduced usage of antibiotics.

Project Documents
• Final Report : the interaction between Pau A and Plaminogen which promotes infection and mastitis by streptococcus uberis   (41k)
Time-Scale and Cost
From: 1999

To: 2003

Cost: £679,375
Contractor / Funded Organisations
Institute for Animal Health (BBSRC)
Animal Diseases              
Animal Health              
GM Non-Food              
Plants and Animals              
Fields of Study
Animal Health