Open AccessComparison of bacterial diversity along the human intestinal tract by direct cloning and sequencing of 16S rRNA genes
Author(s) -
Wang Mei,
Ahrné Siv,
Jeppsson Bengt,
Molin Göran
Publication year - 2005
Publication title -
fems microbiology ecology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.377
H-Index - 155
eISSN - 1574-6941
pISSN - 0168-6496
DOI - 10.1016/j.femsec.2005.03.012
Subject(s) - biology , 16s ribosomal rna , cloning (programming) , genetics , gene , computational biology , ribosomal rna , computer science , programming language
Bacterial diversity of the mucosal biopsies from human jejunum, distal ileum, ascending colon and rectum were compared by analysis of PCR‐amplified 16S rDNA clone libraries. A total of 347 clones from the mucosal biopsies were partially sequenced and assigned to six phylogenetic phyla of the domain Bacteria : Firmicutes , Bacteroidetes , Proteobacteria , Fusobacteria , Verrucomicrobia , and Actinobacteria. The jejunum sample had least microbial diversity compared to the other samples and a trend towards highest diversity in ascending colon was observed. The clone libraries of distal ileum, ascending colon and rectum were not significantly different from each other ( P > 0.0043 ), but they differed significantly from the jejunum library ( P = 0.001 ). The population of sequences retrieved from jejunal biopsies was dominated by sequences closely related to Streptococcus (67%), while the population of sequences derived from distal ileum, ascending colon and rectum were dominated by sequences affiliated with Bacteroidetes (27–49%), and Clostridium clusters XIVa (20–34%) and IV (7–13%). The results indicate that the microbial community in jejunum is different from those in distal ileum, ascending colon and rectum, and that the major phylogenetic groups are similar from distal ileum to rectum.