Effects of Alkali Stress on the Growth and Menaquinone-7 Metabolism of Bacillus subtilis natto.

ABSTRACT: Menaquinone-7 (MK-7) is an important vitamin K₂, synthesized from the menaquinone parent ring and seven isoprene side chains. Presently, the synthesis of MK-7 stimulated by environmental stress primarily focuses on oxygen stress, while the effect of alkali stress is rarely studied. Therefore, this study researched the effects of alkali stress on the fermentation performance and gene expression of Bacillus subtilis natto. The organism's growth characteristics, biomass, sporogenesis, MK-7 biosynthesis, and gene expression were analyzed. After a pH 8.5 stress adaptation treatment for 0.5 h and subsequent fermentation at pH 8.5, which promoted the growth of the strain and inhibited the spore formation rate. In addition, biomass was significantly increased (P < 0.05). T

SUBMITTER: Chen X 

PROVIDER: S-EPMC9096614 | biostudies-literature | 2022

REPOSITORIES: biostudies-literature