Michiel Kleerebezem is to receive a four-hundred-thousand-euro NWO grant for further research into health-promoting bacteria in the human gut. Kleerebezem, professor of Host-Microbe Interactomics, aims to investigate the lifestyle of bifidobacteria.
Bifidobacteria are gut bacteria that suppress other, harmful bacteria and stimulate the absorption of iron, calcium, magnesium and zinc. They are dominant in the guts of infants that receive breastfeeding. In this situation, the 'bifido' population can grow to 80% of the entire gut microbiome. Once children switch to solid foods, the proportion of bifido bacteria gradually shrink until they form only a small percentage of the bacterial community in the guts of adults.
Immune system
In the first stages of life, bifidobacteria play an important part in the development of intestional mucosa and the immune system, Kleerebezem explains. As such, this intial phase plays a crucial role in later health. He wants to better understand how the interaction between bacteria and intestinal mucosa is controlled in this initial stage.
'In the PhD project, we'll zoom in on the role of a small RNA molecule that has a regulating function in the expression of other genes in the bacterium. Earlier research has shown that this sRNA regulates two key functions in the bacterium: the interaction with the host (immunoregulation) and the bacterium's own growth and metabolism. This same research also predicted that this sRNA influences a large number of functions that are key to the lifestyle of the bacterium in the gut.'
Molecular mechanism
Kleerebezem wants to find out which of the bacterium's functions are regulated by the sRNA and confirm their importance for the bacterium's growth and survival in the human gut. 'In addition, we want to unravel the molecular mechanism behind the regulating role of the sRNA to better understand how this molecule works. Once we gain more insight into this regulation, we hope we will be able to influence the gene expression and lifestyle of the bacterium in the gut. This may enable us to point out specific dietary components that reinforce the function of the sRNA.'
Such components may be included in infant formula and baby feed to stimulate the health-promoting effect of these bacteria in young children, Kleerebezem says.
Yoghurt
The bifidobacteria are already added to health-promoting probiotics in foods like yoghurt, but their role in adult guts isn't entirely clear yet, Kleerebezem explains. 'Some studies report improved intestinal function, improved bowel movements, reduced symptoms of gluten allergy and stress reduction, but not all studies support these findings.'
The research is funded through the NWO Open Competition ENW programme, which serves to stimulate fundamental research in the fields of physics and exact sciences.
