Disease relevance of Menaquinone-7

• We recently described the isolation and sequence analysis of a DNA region containing the genes of Bacillus stearothermophilus heptaprenyl diphosphate synthase, which catalyzes the synthesis of the prenyl side chain of menaquinone-7 of this bacterium [1].
• Heptaprenyl diphosphate synthase of Bacillus subtilis, which participates in the biosynthesis of the side chain of menaquinone-7, is composed of two dissociable subunits, component I and component II, which are encoded by two cistrons in a novel gene cluster of gerC operon [Zhang, Y.-W., et al. (1997) J. Bacteriol. 179, 1417-1419] [2].
• Menaquinone-7 in the reaction center complex of the green sulfur bacterium Chlorobium vibrioforme functions as the electron acceptor A1 [3].
• Zeaxanthin and menaquinone-7 biosynthesis in Sphingobacterium multivorum via the methylerythritol phosphate pathway [4].
• This study demonstrates that the effect of vitamin K2 (menaquinone-7) on trabecular bone calcification in rats with skeletal unloading-induced osteopenia is enhanced by zinc in vitro [5].

High impact information on Menaquinone-7

• The plasma levels of vitamin K derivatives [phylloquinone (VK1), menaquinone-4 (MK4), and menaquinone-7 (MK7)] measured were not decreased in patients with HCC, but were significantly increased in MK4 and VK1 + MK4 + MK7 [6].
• Menaquinone-7 was detected in the respiratory chain of strain AW-6(T) [7].
• The gerCC58 mutation maps in a gene encoding the catalytic subunit of the heptaprenyldiphosphate synthase, which is responsible for formation of the isoprenoid side chain of menaquinone-7, and it is proposed that the gerCA, gerCB and gerCC genes be renamed hepA, menG and hepB, respectively [8].
• Menaquinone-7 regulates gene expression in osteoblastic MC3T3E1 cells [9].
• Menaquinone-7 regulates the expressions of osteocalcin, OPG, RANKL and RANK in osteoblastic MC3T3E1 cells [10].

Chemical compound and disease context of Menaquinone-7

• Construction of a Bacillus subtilis (natto) with high productivity of vitamin K2 (menaquinone-7) by analog resistance [11].

Biological context of Menaquinone-7

• The effect of menaquinone-7 (MK-7) on osteoblastic bone formation was investigated [12].

Anatomical context of Menaquinone-7

• The menaquinone-7 level in feces was similar to that in non-warfarin-administered patients [13].
• A slightly halophilic, extremely halotolerant, alkaliphilic, and facultatively anaerobic rod bacterium was isolated from a decomposing marine alga collected in Okinawa, Japan. The isolate, designated O15-7(T), was Gram-positive, endospore-forming, catalase-positive, menaquinone-7-possessing bacterium that is motile by peritrichous flagella [14].

Associations of Menaquinone-7 with other chemical compounds

• Prolonged intake of fermented soybean (natto) diets containing vitamin K2 (menaquinone-7) prevents bone loss in ovariectomized rats [15].

Analytical, diagnostic and therapeutic context of Menaquinone-7

• The quinones were presumed to be menaquinone-7 to -10 by high performance liquid chromatography [16].
• It was estimated that the thermophilic Bacillus having menaquinone-7 dominated in the bioreactor at higher temperature [17].

References