• Journal of Microbiology and Biotechnology
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• 제11권1호
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• pp.106-111
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• 2001

A ${\beta}-galactosidase$ gene of Bifidobacterium adolescentis Int57 (INT57) was cloned using the shotgun method. The sequence of the ${\beta}-galactosidase$ gene existing in the sequenced 3,260-bp fragment showed higher than 40% homology with other bacterial ${\beta}-galactosidase$ genes. The expression in Escherichia coli suggested that the ${\beta}-galactosidase$ might have a monomeric, dimeric, or tetrameric protein structure. This is probably the first peer-reviewed sequence analysis of the ${\beta}-galactosidase$ gene of the genus Bifidobacterium.

• Food Science and Biotechnology
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• 제16권4호
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• pp.655-658
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• 2007

Bacillus polyfermenticus SCD was transformed by the recombinant shuttle vector for Bacillus and Escherichia coli containing 3 antibiotic resistant genes and an ${\alpha}$-amylase gene from Bifidobacterium adolescentis Int57. The ${\alpha}$-amylase gene fused to a secretion sequences was expressed under the control of the promoter of amylase gene from B. subtilis var. natto. The recombinant plasmid was maintained stably in the transformants producing the ${\alpha}$-amylase. The enzyme was secreted to outside of the cell and showed the similar enzyme activity as that of Bacillus subtilis BD170 under the same conditions of pH and growth temperature. Because of the relatively easy transformation and the secretion of the enzyme, the transformants of B. polyfermenticus SCD may give a new strategy in the production of foreign genes.