Abstract
Various microorganisms were screened for high productivity of menaquinone (MK). All eucaryotic microorganisms tested contained only CoQ. The qui-none systems of bacteria and actinomycestes were divided into 3 types: CoQ alone, CoQ and MK, and MK alone. Intracellular MK-6 production was examined in the culture of Flavobacterium meningosepticum. Shikimate, o-succinyl-benzoate, isopentyl alcohol, L-tyrosine and p-hydroxyphenylpyruvatein creased the MK-6 content. The maximal production (21.3 mg/l culture broth and 3.52 mg/g dry cell) was obtained with simultaneous addition of L-tyrosine and iso-pentyl alcohol. A 1-hydroxy-2-naphthoate-resistant mutant, strain HNA 350-22, was found to increase the MK-6 productivity. Another mutant, strain HNA 12-D, produced another type of MK in addition to MK-6. The newly formed product was isolated and identified as MK-5. The total amount of MK reached 55.6 mg/l of culture broth and 9.19 mg/g dry cell in the ratio of MK-5 and MK-6 of 1.7 : 1.
