1 Institute of Microbiology and Hygiene, Charité University Medical Center Berlin, Charitéplatz 1, Berlin, 10117 Germany.
2 Department of Gastroenterology, Lithuanian University of Health Sciences, Kaunas, Lithuania ; Institute for Digestive Research, Lithuanian University of Health Sciences, Kaunas, Lithuania.
3 Institute for Digestive Research, Lithuanian University of Health Sciences, Kaunas, Lithuania.