This invention, vitamin K strengthening thyA (-) the mutation bacterium, and, particular thyA (-) used the mutation body, for example Mammalia (the person) disposal of the vitamin K deficiency and/or the composition for prevention/it regards the production of the product.< Selective figure >Figure 1本発明は、ビタミンK強化thyA(-)突然変異細菌、並びに、当該thyA(-)突然変異体を使用した、哺乳類(例えばヒト)のビタミンK欠乏症の処置及び/又は予防用の組成物/製品の製造に関する。【選択図】図1