著者

Yoshinori TSUKAMOTO Makoto KASAI Hiroyuki KAKUDA

出版者

(社)日本農芸化学会

雑誌

Bioscience, Biotechnology, and Biochemistry (ISSN:09168451)

巻号頁・発行日

vol.65, no.9, pp.2007-2015, 2001 (Released:2002-08-30)

参考文献数

31

被引用文献数

55

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To invent a functional natto promoting bone formation, the construction of a strain with high productivity of vitamin K2 (menaquinone-7: MK-7), which is important in the carboxylation of a kind of bone protein participating in bone formation, osteocalcin, was investigated. To screen for a strain appropriate to making natto (a Japanese traditional fermented soybean food) with high productivity of MK-7, a combination of analog resistance to the compounds on the biosynthetic pathway of menaquinones with mutation was done. Consequently, strain OUV23481, with 2-fold higher productivity (1,719 μg/100 g natto) of MK-7 than that of a commercial strain, was constructed as a mutant with analog resistance to 1-hydroxy-2-naphthoic acid (HNA), p-fluoro-D,L-phenylalanine (pFP), m-fluoro-D,L-phenylalanine (mFP), and β-2-thienytalanine (βTA). This strain was classified as Bacillus subtilis (natto). The natto made using this strain was evaluated to have a good quality as natto in all the viewpoints of appearance, flavor, taste, texture, and stringiness.