51: Food innovation at the heart of future health concerns

The Enzyme and Cellular Engineering Laboratory (GEC), a CNRS-UTC joint unit, combines fundamental and applied research around two main themes. The first, called the "green" theme, concerns everything related to plant metabolism and bioresources with concrete applications, such as the replacement of mineral oils by lipids produced by plants, or the use in nutrition and health of phytosanitary-compounds known for their antioxidant and anti-tumoral properties, such as betanine. The second, the "red" theme, aims to explore the issues of bio-mimetism and biomolecular diversity, in particular by designing biomolecule banks or creating polymers with molecular fingerprints whose recognition performance is comparable to that of antibodies. Innovative research with fields of application ranging from health, to cosmetics and agro-food.

51: Food innovation at the heart of future health concerns

Inhibiting bacterial adhesion

Yannick Rossez is a CNRS research fellow in the UTC-GEC (Enzyme and Cellular Engineering) Laboratory. His work focuses particularly on the bacterial flagellum, responsible for bacterial motility.

His interest in this field? "It was during my post-doc in Scotland and following an epidemic in 2010/2011 that killed more than 50 people that I became interested  in pathogenic host bacteria, which are mainly associated with food poisoning," he says. From then on, Yannick Rossez's objective was "to understand whether pathogens, known in the scientific community to specifically recognize human tissues, had developed strategies to resist in an intermediate host. Namely fruits and vegetables eaten raw". He is interested, in particular, in ‘adhesins’ – the molecules responsible for adhesion - carried by bacteria and the strategy they develop to recognize structures carried only by plants. But one particular adhesin, the bacterial flagellum, is of particular interest to him.

"Known until now as responsible for bacterial motility - displacement of the bacterium - I discovered that it was able to adhere to human tissues via lipids on the cell surface. Without adhesion there is no bacterial pathology," he says. Admitted to UTC in 2016, he continued his work naturally on the flagellum - "a major project", he says - a subject that has a strong impact on the food industry by studying the interaction between lipids and bacterial flagellum in adhesion. He is developing biomimetic membranes, prof. Claire Rossi, in order to understand the mechanisms that make one lipid more favourable to adhesion than another. The result is a discovery that will be published soon:  "The more we eat a diet that is rich in polyunsaturated fatty acids, better known as Omega 3s, the less risk
we run of being colonized by bacteria”, announces Yannick Rossez.

So, what is our current strategy? "It's a question of inhibiting the adhesion process as early as possible, preventing colonisation and therefore the appearance of bacterial pathology and, ultimately, not only reducing the use of antibiotics, but also antibiotic resistance," he explains. Another field of research? "I'm interested in ‘mechanosensing’, a very recent and expanding discipline. Here again, the aim is to inhibit the ability of bacteria to detect surfaces and thereby prevent bacterial adhesion," he concludes.


As a PhD student at the UTC-GEC laboratory, Hélène Cazzola is preparing a thesis entitled "Impact of cell membrane lipid composition on bacterial adhesion via the flagellum", directed by Claire Rossi and Yannick Rossez, which she defended in October 2019.

During her last year as a chemical engineer at ESCOM, Hélène Cazzola also began a Master's degree in biotechnology at UTC. The reason for this choice? "I like scientific multidisciplinarity, especially the interface between chemistry and biology," she explains. And it was during her end-of-year internship at the UTC-GEC that she discovered the world of research. "With Claire Rossi, my intern supervisor, I discovered the world of research and appreciated the opportunity to work on fundamental subjects that could be useful for future applications," she emphasizes. It was with this in mind that she chose her thesis topic on "the adhesion of pathogenic bacteria", she says. "Adhesion is a strategic step in the fight against the persistence of pathogens, the first step before colonization and infection of the host," says Hélène Cazzola.