Construction of a Bacillus subtilis (natto) with high productivity of vitamin K2 (menaquinone-7) by analog resistance.
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 microg/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 beta-2-thienylalanine (betaTA). 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.
Tsukamoto
Y
Y
Central Research Institute, Mitsukan Group Corporation, Handa-shi, Aichi, Japan. ytsukamoto@mitsukan.co.jp
Kasai
M
M
Kakuda
H
H
D000409:Alanine / Q000031:analogs & derivatives* / Q000494:pharmacology; D000818:Animals; D001412:Bacillus subtilis / Q000235:genetics* / Q000378:metabolism*; D002869:Chromosome Aberrations; D006224:Cricetinae; D003412:Cricetulus; D024881:Drug Resistance, Bacterial / Q000235:genetics; D019649:Food Industry / Q000379:methods; D005818:Genetic Engineering / Q000379:methods*; D007218:Industrial Microbiology / Q000379:methods; D009154:Mutation; D009284:Naphthols / Q000494:pharmacology; D010649:Phenylalanine / Q000031:analogs & derivatives* / Q000494:pharmacology; D051381:Rats; D013025:Glycine max; D018675:Toxicity Tests; D024482:Vitamin K 2 / Q000031:analogs & derivatives* / Q000378:metabolism*; D010135:p-Fluorophenylalanine / Q000494:pharmacology
D009284:Naphthols; D024482:Vitamin K 2; C100177:2-thienylalanine; C027218:3-fluorophenylalanine; D010649:Phenylalanine; D010135:p-Fluorophenylalanine; C062629:menaquinone 7; D000409:Alanine; C050175:1-hydroxy-2-naphthoic acid