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Published on: April 9, 2019
Parabacteroides johnsonii sp. nov., isolated from human faeces
Mitsuo Sakamoto1, Maki Kitahara1, Yoshimi Benno1
1Microbe Division/Japan Collection of Microorganisms, RIKEN BioResource Center, Wako, Saitama 351-0198, Japan.
International Journal of Systematic and Evolutionary Microbiology
|February 3, 2007
Summary
A novel bacterial species, Parabacteroides johnsonii, was identified from human feces. This obligate anaerobe is distinct from Parabacteroides merdae based on fermentation tests and genomic analysis.
Area of Science:
- Microbiology
- Bacteriology
- Genomics
Background:
- The human gut microbiome harbors diverse bacterial species.
- Accurate identification and classification of gut bacteria are crucial for understanding host-microbe interactions.
- The genus Parabacteroides includes anaerobic bacteria found in the gastrointestinal tract.
Purpose of the Study:
- To characterize a novel bacterial isolate from human feces.
- To determine the phylogenetic and genomic distinctiveness of the isolate.
- To propose a new species within the Parabacteroides genus.
Main Methods:
- Phenotypic and biochemical characterization.
- Cellular fatty acid and menaquinone profiling.
- 16S rRNA gene sequence analysis.
- DNA-DNA hybridization.
- API 20A tests for fermentation profiling.
Main Results:
- Strain M-165T, isolated from human feces, was identified as a member of the genus Parabacteroides.
- The isolate showed 98% 16S rRNA gene sequence similarity to Parabacteroides merdae.
- Phenotypic characteristics were similar to P. merdae, but fermentation of L-arabinose and L-rhamnose differed.
- DNA-DNA hybridization revealed
- The DNA G+C content was 47.6 mol%.
Conclusions:
- Strain M-165T represents a novel species of the genus Parabacteroides.
- The proposed name for this new species is Parabacteroides johnsonii sp. nov.
- The type strain is M-165T (=JCM 13406T=DSM 18315T).
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