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Acquired tolerance to oxidative stress in Bifidobacterium longum 105-A via expression of a catalase gene.

ABSTRACT: For improvement of tolerance to oxidative stress in Bifidobacterium longum 105-A, we introduced the Bacillus subtilis catalase gene (katE) into it. The transformant showed catalase activity (39 U/mg crude protein) in the intracellular fraction, which increased survival by ?100-fold after a 1-h exposure to 4.4 mM H(2)O(2), decreased de novo H(2)O(2) accumulation, and increased survival in aerated cultures by 10(5)-fold at 24 h. The protection level was better than that conferred by exogenously added catalase.

SUBMITTER: He J

PROVIDER: S-EPMC3318838 | biostudies-other | 2012 Apr

REPOSITORIES: biostudies-other

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Acquired tolerance to oxidative stress in Bifidobacterium longum 105-A via expression of a catalase gene.

He Jianlong J Sakaguchi Kouta K Suzuki Tohru T

Applied and environmental microbiology 20120203 8

For improvement of tolerance to oxidative stress in Bifidobacterium longum 105-A, we introduced the Bacillus subtilis catalase gene (katE) into it. The transformant showed catalase activity (39 U/mg crude protein) in the intracellular fraction, which increased survival by ∼100-fold after a 1-h exposure to 4.4 mM H(2)O(2), decreased de novo H(2)O(2) accumulation, and increased survival in aerated cultures by 10(5)-fold at 24 h. The protection level was better than that conferred by exogenously ad ...[more]

PMID: 22307289

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Dataset Information

Acquired tolerance to oxidative stress in Bifidobacterium longum 105-A via expression of a catalase gene.

Publications

Acquired tolerance to oxidative stress in Bifidobacterium longum 105-A via expression of a catalase gene.

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