2009年4月
Conversion of cholic acid and chenodeoxycholic acid into their 7-oxo derivatives by Bacteroides intestinalis AM-1 isolated from human feces
FEMS MICROBIOLOGY LETTERS
- 巻
- 293
- 号
- 2
- 開始ページ
- 263
- 終了ページ
- 270
- 記述言語
- 英語
- 掲載種別
- 研究論文(学術雑誌)
- DOI
- 10.1111/j.1574-6968.2009.01531.x
- 出版者・発行元
- WILEY-BLACKWELL PUBLISHING, INC
Secondary bile acid-producing bacteria were isolated from human feces to improve our appreciation of the functional diversity and redundancy of the intestinal microbiota. In total, 619 bacterial colonies were isolated using a nutrient-poor agar medium and the level of secondary bile acid formation was examined in each by a liquid culture, followed by thin-layer chromatography. Of five strains analyzed by 16S rRNA gene sequencing and biochemical testing, one was identified as Bacteroides intestinalis AM-1, which was not previously recognized as a secondary bile-acid producer. GC-MS revealed that B. intestinalis AM-1 converts cholic acid (CA) and chenodeoxycholic acid into their 7-oxo derivatives, 7-oxo-deoxycholic acid (7-oxo-DCA) and 7-oxo-lithocholic acid, respectively. Thus, B. intestinalis AM-1 possesses 7 alpha-hydroxysteroid dehydrogenase (7 alpha-HSDH) activity. In liquid culture, B. intestinalis AM-1 showed a relatively higher productivity of 7-oxo-DCA than Escherichia coli HB101 and Bacteroides fragilis JCM11019(T), which are known to possess 7 alpha-HSDH activity. The level of 7 alpha-HSDH activity was higher in B. intestinalis AM-1 than in the other two strains under the conditions tested. The 7 alpha-HSDH activity in each of the three strains is not induced by CA; instead, it is regulated in a growth phase-dependent manner.
- リンク情報
- ID情報
-
- DOI : 10.1111/j.1574-6968.2009.01531.x
- ISSN : 0378-1097
- Web of Science ID : WOS:000264240900014