AUTHOR=Montassier Emmanuel , Al-Ghalith Gabriel A. , Mathé Camille , Le Bastard Quentin , Douillard Venceslas , Garnier Abel , Guimon Rémi , Raimondeau Bastien , Touchefeu Yann , Duchalais Emilie , Vince Nicolas , Limou Sophie , Gourraud Pierre-Antoine , Laplaud David A. , Nicot Arnaud B. , Soulillou Jean-Paul , Berthelot Laureline TITLE=Distribution of Bacterial α1,3-Galactosyltransferase Genes in the Human Gut Microbiome JOURNAL=Frontiers in Immunology VOLUME=10 YEAR=2020 URL=https://www.frontiersin.org/journals/immunology/articles/10.3389/fimmu.2019.03000 DOI=10.3389/fimmu.2019.03000 ISSN=1664-3224 ABSTRACT=

Because of a loss-of-function mutation in the GGTA1 gene, humans are unable to synthetize α1,3-Galactose (Gal) decorated glycans and develop high levels of circulating anti-α1,3-Galactose antibodies (anti-Gal Abs). Anti-Gal Abs have been identified as a major obstacle of organ xenotransplantation and play a role in several host-pathogen relationships including potential susceptibility to infection. Anti-Gal Abs are supposed to stem from immunization against the gut microbiota, an assumption derived from the observation that some pathogens display α1,3-Gal and that antibiotic treatment decreases the level of anti-Gal. However, there is little information to date concerning the microorganisms producing α1,3-Gal in the human gut microbiome. Here, available α1,3-Galactosyltransferase (GT) gene sequences from gut bacteria were selectively quantified for the first time in the gut microbiome shotgun sequences of 163 adult individuals from three published population-based metagenomics analyses. We showed that most of the gut microbiome of adult individuals contained a small set of bacteria bearing α1,3-GT genes. These bacteria belong mainly to the Enterobacteriaceae family, including Escherichia coli, but also to Pasteurellaceae genera, Haemophilus influenza and Lactobacillus species. α1,3-Gal antigens and α1,3-GT activity were detected in healthy stools of individuals exhibiting α1,3-GT bacterial gene sequences in their shotgun data.