Marie Schöpping, industrial PhD student at the Division of Industrial Biotechnology at Chalmers, and Chr. Hansen A/S, is part of the project where two tools to investigate the metabolism of bifidobacteria have been delveoped, Image courtesy of Chr. Hansen A/S (photo of bifidobacteria)
Bifidobacteria are bacteria that contribute to a healthy gut microbiome in both humans and animals. These bacteria can be used as probiotics, which are dietary supplements with added live bacteria, to achieve several positive health effects.
In the study, the researchers at Chr. Hansen A/S and Chalmers developed two valuable tools for studying the metabolism and physiology of probiotic bifidobacteria.
“The strains we studied are used in existing health-promoting probiotic products. The tools we have developed will help us understand how these probiotic microorganisms behave during the cultivation process of the production. It can also help us understand how the bacteria behave in their natural environment, for example, the human gut” says Carl Johan Franzén, Professor in Bioreaction Engineering.
Model simulates how the cell uses part of the metabolism
The first tool is a mathematical model which describes all the biochemical reactions involved in the metabolism of an organism.
Dr. Ahmad Zeidan is leading the project at Chr. Hansen A/S. He explains:
“This is called a genome-scale metabolic model, or ‘GEM’. The GEM can be used to simulate how a cell uses its metabolism for growth and production of chemical compounds under different environmental conditions. Moreover, it serves as a framework for interpreting results from many different experiments. To make accurate predictions, the GEM must be very detailed and must be created for the specific strain of the bacterium that is being studied.”
Defined growth medium for better analysis
The researchers developed GEMs for two industrially relevant probiotic bifidobacterial strains, and used them to develop the second tool, which is a chemically defined cultivation medium in which the cells are cultured.
“This medium contains all nutrients that are required for the two bifidobacterial strains to grow. Since all of the nutrients and their concentrations are known, it allows us to measure and interpret the behaviour of the bacteria more accurately than with the standard growth medium,” says Marie Schöpping, industrial PhD student at Chr. Hansen A/S and the Division of Industrial Biotechnology, Chalmers.
The research combining the two tools will lead to more reliable, resource-efficient and sustainable production processes of the bacteria. Improved knowledge of the bacteria’s metabolism may also contribute to improvement of their high health-promoting activities, through a better design of the cultivation process.
About the study
The study is part of Marie Schöpping’s industrial PhD project, which is a collaboration between Chalmers and Chr. Hansen A/S, a global supplier of microorganisms for the food industry, among other things.
The project is jointly funded by Innovation Fund Denmark and Chr. Hansen A/S. In the project, Marie Schöpping will use the GEMs and the defined medium to investigate how probiotic bacteria are affected by different factors during their production.
Read the study: Identifying the essential nutritional requirements of the probiotic bacteria Bifidobacterium animalis and Bifidobacterium longum through genome-scale modeling