Send to

Choose Destination
Curr Microbiol. 1999 Sep;39(3):123-8.

Phylogenetic study of methanogens associated with rumen ciliates.

Author information

Laboratory of Animal Science, Faculty of Agriculture, Kyoto Prefectural University, Shimogamo, Kyoto 606-8522, Japan.


The phylogeny of methanogenic archaea associated with ciliate protozoa in a sheep rumen was investigated. Ruminal ciliate protozoa were exhaustively washed and mixtures of genomic DNA extracted. Archaea-specific nested PCR amplification was conducted with the ciliate genomic mixture. The resultant small subunit (16S) ribosomal RNA gene (ssu rDNA) was cloned into Escherichia coli JM 109. Many methanogens were still observed on and/or in ciliate cells by fluorescent microscopy even after exhaustive washing with buffer. Partial sequences of ssu rDNA close to Methanobrevibacter smithii were dominant in the retrieved sequences. RFLP analyses on the retrieved sequences revealed the absence of Methanobrevibacter ruminantium in the protozoal preparation. The association of Methanobrevibacter spp. with ruminal ciliate protozoa was demonstrated by the isolation of archaeal ssu rDNA phylogenetically close to that of M. smithii.

[Indexed for MEDLINE]

Supplemental Content

Full text links

Icon for Springer
Loading ...
Support Center