THE REAL RISK OF ANTIBIOTIC RESISTANCE
The threat of deadly pathogenic antibioticresistant bacteria has become very real recently, in some cases with fatal consequences. Foodborne bacteria are known to carry resistance to some antibiotics, and they can transfer their resistance to less genial species. It is estimated that a quarter of food production involves microbial fermentation, and such food can contain several million lactic acid bacteria per gram. By feeding it to animals and eating it ourselves, we may be continually making genes for antibiotic resistance available to pernicious organisms that have potential to kill if we are unable to treat them. Yet the scale of this problem is not known. There are no data on the extent of antibiotic resistance in bacteria used in food and we do not know how easily resistance transfers between different bacteria in natural environments.
A project funded under the Sixth Framework Programme is studying antibiotic resistance in bacteria used in the food chain, with a view to evaluating this risk. Assessment and Critical Evaluation of Antibiotic Resistance Transferability in food chain, or ACE-ART, is a Specific Targeted Research Project involving 14 European institutions. It hopes to improve our understanding of the dynamics of antibiotic resistance amongst bacteria in both the environment andour bodies.
TESTING THE RESISTANCE
The research will be the first to test naturally occurring, non-disease bacteria for their ability to withstand antibiotics. It focuses on species used commercially as starter cultures for probiotic and fermented food: Lactobacillus, Bifidobacterium, Lactococcus and Streptococcus thermophilus. Strains isolated from natural habitats, including animal and human guts, plants and dairy products, will be assessed for resistance to common antibiotics. In addition, strains isolated before 1950, when antibiotics were introduced, will be compared with post-antibiotic strains to see how much resistance has developed in response to antibiotic use.
To find out how easily antibiotic resistance is transferred, resistant bacteria will be assembled with non-resistant bacteria of different strains, in experimental gut or plant environments. The 'model' human gut comprises a population of laboratory rats carrying human gut flora. The non-resistant strains, including disease organisms such as Listeria and Salmonella, will then be tested for acquired resistance. If the resistance transfers more easily between bacteria when their environment is treated with antibiotics, this may show how widespread antibiotic use in medicine and agriculture promotes the spread of antibiotic resistance.
CRACKING THE CODE
The final thread of the project is to locate the genes or mutations responsible for resistance. Where they are in the bacterial genome reveals a lot about their mobility. If they are in mobile circular pieces of DNA known as plasmids, they are very prone to transfer between bacteria. If they are in the bacterial chromosomes, they may be associated with mobile DNA elements and may also transfer easily. This work will enable the development of DNA tests for antibiotic resistance in food-borne bacteria.
A relevant role will be played by EFFCA, the European association of producers of feed and food starter cultures. A better understanding of antibiotic resistance and the conditions that promote its spread should help companies to minimise the risk of transferring it to the environment via the food chain.
List of Partners
- Istituto di Microbiologia, Universitą Cattolica del Sacro Cuore (Italy)
- Institute of Food Safety and Nutrition (Denmark)
- Instytut Biochemii i Biofizyki PAN (Poland)
- TEAGASC, The National Food Centre (Ireland)
- RIKILT Institute of Food Safety - MCB (The Netherlands)
- Chr. Hansen A/S (Denmark)
- Instituto de Productos Lįcteos de Asturias, Consejo Suprerior de Investigaciones Cientificas (Spain)
- VTT Biotechnology (Finland)
- Institute of Applied Biotechnology, University of Kuopio (Finland)
- Department of Dairy Research and Bacteriology, BOKU (Austria)
- Laboratorium voor Microbiologie, Ghent University (Belgium)
- Department of Gastrointestinal and Parasitic Infections, Statens Serum Institut (Denmark)
- Norwegian Food Research Institute (Norway)
- Swedish National Food Administration (Sweden)
- Full title:
- Assessment and critical evaluation of antibiotic resistance transferability in food chain
- Contract n°:
- Project co-ordinator:
- Lorenzo Morelli, Universitą Cattolica del Sacro Cuore, Istituto di Microbiologia, Lorenzo.firstname.lastname@example.org
- EC Scientific Officer:
- Judit Krommer, email@example.com
- EU contribution:
- € 2.5M
- Specific Targeted Research Project