| Title |
Novel Bifidobacterium Promoters Selected Through Microarray Analysis Lead to Constitutive High-Level Gene Expression |
| Author |
Yan Wang1, Jin Yong Kim1, Myeong Soo Park2,3*, and Geun Eog Ji1,3* |
| Address |
1Department of Food and Nutrition, Research Institute of Human Ecology, Seoul National University, Seoul 151-742, Republic of Korea, 2Department of Hotel Culinary Arts, Anyang Science University, Anyang 430-749, Republic of Korea, 3Research Institute, BIFIDO Co., Ltd. Hongchun 250-804, Republic of Korea |
| Bibliography |
Journal of Microbiology, 50(4),638-643, 2012,
|
| DOI |
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| Key Words |
Bifidobacterium, promoter, expression, vector |
| Abstract |
For the development of a food-grade expression system for Bifidobacterium, a strong promoter leading to high-level expression of cloned gene is a prerequisite. For this purpose, a promoter screening host-vector system for Bifidobacterium has been established using β-glucosidase from Bifidobacterium lactis as a reporter and Bifidobacterium bifidum BGN4 as a host, which is β-glucosidase negative strain. Seven putative promoters showing constitutive high-level expression were selected through microarray analysis based on the genome sequence of B. bifidum BGN4. They were cloned into upstream of β-glucosidase gene and transformed into Escherichia coli DH5α and B. bifidum BGN4. Promoter activities were analyzed both in E. coli and B. bifidum BGN4 by measuring β-glucosidase activity. β-Glucosidase activities in all of the transformants showed growth-associated characteristics. Among them, P919 was the strongest in B. bifidum BGN4 and showed maximum activity at 18 h, while P895 was the strongest in E. coli DH5α at 7 h. This study shows that novel strong promoters such as P919 can be used for high-level expression of foreign genes in Bifidobacterium and will be useful for the construction of an efficient food-grade expression system. |
