1. Laboratory of Molecular Microbiology, Biology Department, Universitat de Girona, Girona, Spain
2. Department of Gastroenterology, Hospital Universitari Dr. Josep Trueta, Girona, Spain
3. Department of Gastroenterology, Hospital Santa Caterina, Salt, Girona, Spain
4. Microbial Ecology Group, Rowett Institute of Nutrition and Health, University of Aberdeen, Aberdeen, United Kingdom