title: Detection of Helicobacter species in the gastrointestinal tract of ringtail possum and koala: possible influence of diet, on the gut microbiota.
abstract: The presence of Helicobacter spp. was examined in the liver and in different regions of the gastrointestinal tract (GIT) including the stomach, 3 cm above ileum, ileum, caecum, colon and rectum of 10 ringtail possums (RTPs) and 3 koalas using a combination of microscopy, culture and PCR. Helicobacter was detected in the distal end of the GIT of 7 of 10 RTPs by direct PCR and in all (10/10) RTPs by nested PCR. Five 'S' shaped isolates with bipolar sheathed flagella were isolated from the lower bowel of 3 of the 10 RTPs. 16S rRNA sequence analysis of these 5 isolates confirmed them as potentially novel Helicobacter species. No Helicobacter species were cultured from the koalas, however Helicobacter DNA was detected, in the majority of liver and/or stomach samples of the three koalas and in the colonic region of one koala, using nested PCR. The 16S rRNA gene was sequenced directly from DNA extracted from the homogenised livers and mucus scrapings of the stomach from koala 1 and were confirmed to be Helicobacter species. Based on histopathological examination of sections from the liver and intestine no evidence of infection could be related to the presence of helicobacters in either the RTP or koala. Based on our results, it is possible that diet may influence the detection of Helicobacter species; however this required further investigation.
authors.affiliation: School of Biotechnology and Biomolecular Sciences, University of New South Wales, Sydney, NSW 2052, Australia.
authors.forename: Thosaporn
authors.initials: T
authors.lastname: Coldham
authors.forename: Karrie
authors.initials: K
authors.lastname: Rose
authors.forename: Jani
authors.initials: J
authors.lastname: O'Rourke
authors.forename: Brett A
authors.initials: BA
authors.lastname: Neilan
authors.forename: Helen
authors.initials: H
authors.lastname: Dalton
authors.forename: Adrian
authors.initials: A
authors.lastname: Lee
authors.forename: Hazel
authors.initials: H
authors.lastname: Mitchell
mesh_terms: D000821:Animal Feed / Q000032:analysis; D000818:Animals; D004269:DNA, Bacterial / Q000235:genetics; D004032:Diet; D005260:Female; D041981:Gastrointestinal Tract / Q000382:microbiology*; D016998:Helicobacter / Q000145:classification / Q000235:genetics / Q000302:isolation & purification*; D008099:Liver / Q000382:microbiology; D008297:Male; D008394:Marsupialia / Q000378:metabolism / Q000382:microbiology*; D064307:Microbiota; D048368:Phascolarctidae / Q000378:metabolism / Q000382:microbiology*
chemical_list: D004269:DNA, Bacterial
keywords: Helicobacter species; Koala; Phylogenetic study; Ringtail possum; Transmission electron microscopy