1 Institute of Medical Microbiology, RWTH University Hospital Aachen, Aachen, Germany. n.vanbest@maastrichtuniversity.nl.
2 Department of Medical Microbiology, School of Nutrition and Translational Research in Metabolism (NUTRIM), Maastricht University, Maastricht, The Netherlands. n.vanbest@maastrichtuniversity.nl.
3 Departments of Biochemistry and Microbiology and of Anthropology, and Institute for Food, Nutrition and Health, Rutgers University, New Brunswick, NJ, USA. mg.dominguez-bello@rutgers.edu.
4 Institute of Medical Microbiology, RWTH University Hospital Aachen, Aachen, Germany. mhornef@ukaachen.de.
5 Department of Computational and Systems Biology, Department of Obstetrics, Gynecology and Reproductive Sciences, Magee-Womens Research Institute, University of Pittsburgh School of Medicine, PA, Pittsburgh, USA. jasarevice@mwri.magee.edu.
6 Human Microbiome Research Program, Faculty of Medicine, University of Helsinki, Helsinki, Finland. katri.korpela@helsinki.fi.
7 Wellcome Sanger Institute and Microbiotica, Cambridge, UK. tl2@sanger.ac.uk.