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