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Genomic insights into the physiology of Quinella, an iconic uncultured rumen bacterium.

ABSTRACT: Quinella is a genus of iconic rumen bacteria first reported in 1913. There are no cultures of these bacteria, and information on their physiology is scarce and contradictory. Increased abundance of Quinella was previously found in the rumens of some sheep that emit low amounts of methane (CH₄) relative to their feed intake, but whether Quinella contributes to low CH₄ emissions is not known. Here, we concentrate Quinella cells from sheep rumen contents, extract and sequence DNA, and reconstruct Quinella genomes that are >90% complete with as little as 0.20% contamination. Bioinformatic analyses of the encoded proteins indicate that lactate and propionate formation are major fermentation pathways. The presence of a gene encoding a potential uptake hydrogenase suggests that Quinella might be able to use free hydrogen (H₂). None of the inferred metabolic pathways is predicted to produce H₂, a major precursor of CH₄, which is consistent with the lower CH₄ emissions from those sheep with high abundances of this bacterium.

SUBMITTER: Kumar S

PROVIDER: S-EPMC9585023 | biostudies-literature | 2022 Oct

REPOSITORIES: biostudies-literature

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Genomic insights into the physiology of Quinella, an iconic uncultured rumen bacterium.

Kumar Sandeep S Altermann Eric E Leahy Sinead C SC Jauregui Ruy R Jonker Arjan A Henderson Gemma G Kittelmann Sandra S Attwood Graeme T GT Kamke Janine J Waters Sinéad M SM Patchett Mark L ML Janssen Peter H PH

Nature communications 20221020 1

Quinella is a genus of iconic rumen bacteria first reported in 1913. There are no cultures of these bacteria, and information on their physiology is scarce and contradictory. Increased abundance of Quinella was previously found in the rumens of some sheep that emit low amounts of methane (CH<sub>4</sub>) relative to their feed intake, but whether Quinella contributes to low CH<sub>4</sub> emissions is not known. Here, we concentrate Quinella cells from sheep rumen contents, extract and sequence ...[more]

PMID: 36266280

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Dataset Information

Genomic insights into the physiology of Quinella, an iconic uncultured rumen bacterium.

Publications

Genomic insights into the physiology of Quinella, an iconic uncultured rumen bacterium.

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