Controlled gene expression in bifidobacteria by use of a bile-responsive element.
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ABSTRACT:
SUBMITTER: Ruiz L
PROVIDER: S-EPMC3255758 | biostudies-literature | 2012 Jan
REPOSITORIES: biostudies-literature
Publications
Controlled gene expression in bifidobacteria by use of a bile-responsive element.
Ruiz Lorena L Álvarez-Martín Pablo P Mayo Baltasar B de los Reyes-Gavilán Clara G CG Gueimonde Miguel M Margolles Abelardo A
Applied and environmental microbiology 20111111 2
The promoter activity of the upstream region of the bile-inducible gene betA from Bifidobacterium longum subsp. longum NCC2705 was characterized. DNA fragments were cloned into the reporter vector pMDYAbfB, and the arabinofuranosidase activity was determined under different in vitro conditions. A segment of 469 bp was found to be the smallest operational unit that retains bile inducibility. The reporter activity was strongly affected by the presence of ox gall, cholate, and conjugated cholate, b ...[more]
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