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Anna Samarra Mas

Postdoctoral Fellow

Interests

Research Interests

  • Human Milk and HMOs
  • Antimicrobial Resistance
  • Maternal-Infant Gut Microbiome

At the Bench

Anna is a researcher with a PhD focused on antibiotic resistance in early life and the factors shaping the infant gut resistome during the first year of life. Her work integrates microbiome profiling, metagenomics, and human milk composition analysis, with a particular emphasis on human milk oligosaccharides (HMOs) and their role in microbial colonization and resistance gene dynamics. She has experience working with longitudinal cohort datasets to investigate how perinatal factors such as delivery mode, breastfeeding, and maternal characteristics influence microbial and functional development. Currently, Anna is interested in translating these findings into a deeper mechanistic understanding of host–microbiome interactions and their long-term implications for immune and respiratory outcomes in infants.

Outside of Lab

In her free time, Anna enjoys staying active through sports, especially surfing, hiking, and working out at the gym. She also likes going for runs on the weekends and rewarding herself afterwards with an acai bowl. In addition, Anna enjoys sewing and crocheting, travelling, and spending time with her dog, Lluca.

Background and Education

Education

University Degree Year Field
University of California San Diego, La Jolla CA Postdoc 2025-present Human Milk and Microbiome
Politechnic University of Valencia, Valencia, Spain Ph.D. 2021-2025 Biotechnology
Universitat de Barcelona, Barcelona, Spain M.Sc. 2021 Advanced Microbiology
Universitat Rovira i Virgili, Tarragona, Spain B.Sc. 2020 Biotechnology

 

Honors and Publications

Honors

Year Honor
2022-2023 Short-term Predoctoral Mobility Fellowship, Generalitat Valenciana
2021 Predoctoral Fellowship, Generalitat Valenciana

 

Publications

Samarra A, Alcañiz AJ, Martínez-Costa C, et al. Breastfeeding and early Bifidobacterium-driven microbial colonization shape the infant gut resistome. Nat Commun. 2025;16(1):6099. Published 2025 Jul 2. doi:10.1038/s41467-025-61154-w

Samarra A, Renwick S, Arzamasov AA, et al. Human milk oligosaccharide metabolism and antibiotic resistance in early gut colonizers: insights from bifidobacteria and lactobacilli in the maternal-infant microbiome. Gut Microbes. 2025;17(1):2501192. doi:10.1080/19490976.2025.2501192

Samarra, A., Cabrera-Rubio, R., Martínez-Costa, C., & Collado, M. C. (2024). The role of Bifidobacterium genus in modulating the neonate microbiota: implications for antibiotic resistance acquisition in early life. Gut Microbes, 16(1). https://doi.org/10.1080/19490976.2024.2357176

Samarra A, Cabrera-Rubio R, Martínez-Costa C, Collado MC. Unravelling the evolutionary dynamics of antibiotic resistance genes in the infant gut microbiota during the first four months of life. Ann Clin Microbiol Antimicrob. 2024 Aug 13;23(1):72. doi: 10.1186/s12941-024-00725-z.

Samarra A, Flores E, Bernabeu M, et al. Shaping Microbiota During the First 1000 Days of Life. Adv Exp Med Biol. 2024;1449:1-28. doi:10.1007/978-3-031-58572-2_1

Samarra A, Esteban-Torres M, Cabrera-Rubio R, et al. Maternal-infant antibiotic resistance genes transference: what do we know?. Gut Microbes. 2023;15(1):2194797. doi:10.1080/19490976.2023.2194797