Journal of Microbiology

Research Support, Non-U.S. Gov't

Diversity of Bovine Rumen Methanogens In Vitro in the Presence of Condensed Tannins, as Determined by Sequence Analysis of 16S rRNA Gene Library: Hui Yin Tan , Chin Chin Sieo , Chin Mei Lee , Norhani Abdullah , Juan Boo Liang , Yin Wan Ho; J. Microbiol. 2011;49(3):492-498. Published online June 30, 2011; DOI: https://doi.org/10.1007/s12275-011-0319-7

Abstract: Molecular diversity of rumen archaeal populations from bovine rumen fluid incubated with or without condensed tannins was investigated using 16S rRNA gene libraries. The predominant order of rumen archaea in the 16S rRNA gene libraries of the control and condensed tannins treatment was found to belong to a novel group of rumen archaea that is distantly related to the order Thermoplasmatales, with 59.5% (15 phylotypes) and 81.43% (21 phylotypes) of the total clones from the control and treatment clone libraries, respectively. The 16S rRNA gene library of the control was found to have higher proportions of methanogens from the orders Methanomicrobiales (32%) and Methanobacteriales (8.5%) as compared to those found in the condensed tannins treatment clone library in both orders (16.88% and 1.68% respectively). The phylotype distributed in the order Methanosarcinales was only found in the control clone library. The study indicated that condensed tannins could alter the diversity of bovine rumen methanogens.

Research Support, U.S. Gov't, Non-P.H.S.

A Novel Archaeal Group in the Phylum Crenarchaeota Found Unexpectedly in an Eukaryotic Survey in the Cariaco Basin: Sun-Ok Jeon , Tae-Seok Ahn , Sun-Hee Hong; J. Microbiol. 2008;46(1):34-39.; DOI: https://doi.org/10.1007/s12275-007-0247-8

Abstract: Archaea have been found in many more diverse habitats than previously believed due in part to modern molecular approaches to discovering microbial diversity. We report here an unexpected expansion of the habitat diversity of the Archaea in the Cariaco Basin we found using a primer set designed for 18S eukaryotic rDNA sequence analysis. The results presented here expand the originally identified 9 archaeal clones reported in this environment using bacterial/archaeal primers to 152 archaeal clones: 67 (18 OTU) of these clones were found at a depth of 900 m of station A while 71 (9 OTU) of them were at a depth of between 300~335 m of station B&C depending upon which location the samples were taken. We used three phylogenetic analysis methods and detected 20 phylotypes belonging to a single previously unreported group distantly related to the Crenarchaeota. Also, we determined that the original nine sequences did not fall into any of the known phyla of the Archaea suggesting that they may represent a novel group within the Kingdom Archaea. Thus, from these two studies, we suggest that Archaea in the Cariaco Basin could be unique; however, further studies using archaeal-specific primers and the design of new primers as well as the systematic use of several different primer combinations may improve the chances of understanding the archeal diversity in the Cariaco Basin.

Search