Original title: Menaquinone biosynthesis in Lactococcus lactis: Recent advances and future prospects
Yu Lou, Jingjing Shuang, Jian Kong, Tingting Guo · September 2026
People need vitamin K2, also called menaquinone, for healthy bones and heart protection. The molecule has a chemical ring attached to a chain of repeating units, labeled as MK-n based on the unit count. Long-chain types, where n is 5-13, last longer in the body and absorb better than short-chain types. However, only bacteria can make these long-chain versions. To address this, researchers reviewed how to produce them using Lactococcus lactis, a bacterium common in dairy processing that naturally makes MK-8, MK-9, and MK-10. Scientists have improved production using fermentation optimization, metabolic engineering, and physiological studies. They also examined methods from Escherichia coli and Bacillus subtilis to help turn Lactococcus lactis into an efficient cell factory for vitamins.
You are baking cookies and need vanilla extract. The cheap kind evaporates quickly, so you have to add more. But you discover that a special ingredient naturally makes a version that lasts through the whole batch. Here, the special ingredient is a bacterium used in dairy, and the long-lasting version is a form of vitamin K2 with a longer side chain that the body absorbs better.
Vitamin K2 supplements are used for bone and heart health, but the short-chain forms in most supplements don't stay in the body long. This review shows that a common dairy bacterium naturally makes long-chain K2, which lasts longer and is better absorbed. If scientists can boost its production, we could get more effective K2 from fermented foods or supplements.
This is a review, not a new experimental study. It does not provide new data on production yields or novel engineering strategies. The discussion of high-yield schemes in other bacteria is for insight, not direct application. The review does not address challenges in scaling up production or regulatory hurdles for using engineered L. lactis in food.
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Menaquinone biosynthesis in Lactococcus lactis: Recent advances and future prospects — Yu Lou, Jingjing Shuang, Jian Kong et al. — Engineering microbiology — doi:10.1016/j.engmic.2026.100304
Abstract licence: CC BY
Explanation generated by Synthesis from the abstract — it is not the original paper.