Doctoral Defense in Food Science

On Tuesday, April 1, 2025, Clara Anne Thérèse Jégousse will defend her doctoral dissertation in food science at the Faculty of Food Science and Nutrition at the University of Iceland. The dissertation is titled: Exploration of microbial communities from Icelandic marine waters using metagenomics.

Opponents are Dr. Alexander Sczyrba, professor at Bielefeld University, Germany, and Dr. Ian Salter, research director at Havstovan – the Marine Research Institute of the Faroe Islands.

The supervisor was Dr. Viggó Þór Marteinsson, professor at the Faculty of Food Science and Nutrition. Additionally, Dr. María Guðjónsdóttir, professor at the same faculty, was a co-supervisor. The doctoral committee also included Dr. René Groben, project manager at Matís, Dr. Pauline Vannier, lecturer at Université de Toulon, and Dr. Arnar Pálsson, professor at the Faculty of Life and Environmental Sciences.

Ólöf Guðný Geirsdóttir, Dean of the Faculty of Food Science and Nutrition, will chair the ceremony, which will take place in the in Hátíðarsalur in the Main building of University of Iceland at 1:00 PM.

Abstract
Marine microorganisms are vital in maintaining ocean health by supporting food webs and regulating biogeochemical cycles. The ocean around Iceland, where warm Atlantic and cold Arctic currents meet, is a unique marine environment. While primary production in Icelandic waters has been monitored since the 1950s with microscopy and satellite imaging, molecular insights into microbial taxonomic and metabolic diversity remain limited. This thesis investigates the microbial communities in Icelandic marine waters using metagenomics. The main objectives were to find out what species can be detected in Icelandic marine waters? in what proportions? what is their potential function in the marine ecosystem? and how do environmental factors shape their distribution?
The findings of this thesis offer insights into the relationships between microbial communities and their environments, establishing a foundation for future research. The publicly available datasets from this study serve as a baseline, supporting ecosystem modelling and sustainable management of Icelandic marine waters in a changing climate.

About the doctoral candidate
Clara Anne Thérèse Jégousse was born in France in 1991. She obtained a BS degree in chemistry in 2014 and a master's degree in bioinformatics in 2016 from the University of Nantes in France. She moved to Iceland and began her doctoral studies in 2017 under the supervision of Professor Viggó Marteinsson. Clara is married to Tómas Ármann Hafsteinsson, and they have a daughter, Viktoría Margrét, born in 2023.