Advances in regulating vitamin K production through metabolic engineering strategies.

Vitamin K (menaquinone, VK, MK) is an essential lipid-soluble vitamin that plays critical roles in inhibiting cell ferroptosis, improving blood clotting, and preventing osteoporosis. The increased global demand for VK has inspired interest in novel production strategies. In this review, various novel metabolic regulation strategies, including static and dynamic metabolic regulation, are summarized and discussed.

Enhanced vitamin K2 production by engineered Bacillus subtilis during leakage fermentation.

Menaquinone-7 (MK-7), a valuable member of the vitamin K2 series, is an essential nutrient for humans. It is used for treating coagulation disorders, and osteoporosis, promoting liver function recovery, and preventing cardiovascular diseases. In this study, to further improve the metabolic synthesis of MK-7 by the mutant strain, the effect of surfactants on the metabolic synthesis of MK-7 by the mutant strain Bacillus subtilis 168 KO-SinR (BS168 KO-SinR) was analyzed.

Poly-γ-Glutamic Acid Production by Engineering a DegU Quorum-Sensing Circuit in .

As a natural biological macromolecule, γ-polyglutamic acid (γ-PGA) plays a significant role in medicine, food, and cosmetic industries owing to its unique properties of biocompatibility, biodegradability, water solubility, and viscosity. Although many strategies have been adopted to increase the yield of γ-PGA in , the effectiveness of these common approaches is not high because the strong viscosity affects cell growth. However, dynamic regulation based on quorum sensing (QS) has been extensively applied as a fundamental tool for fine-tuning gene expression in reaction to changes in cell density without adding expensive inducers.