Enhancement of 1,4-dihydroxy-2-naphthoic acid production by Propionibacterium freudenreichii ET-3 fed-batch culture.
The production of 1,4-dihydroxy-2-naphthoic acid (DHNA) was investigated using a fed-batch culture of Propionibacterium freudenreichii ET-3. DHNA is a precursor of menaquinone (MK) and is transformed to MK by combination with an isoprenoid unit. We found that ET-3 stopped MK production and increased DHNA production in an anaerobic fed-batch culture by maintaining the lactose concentration at approximately zero. The maximum DHNA concentration observed in the anaerobic fed-batch culture was markedly higher than the maximum DHNA concentration observed in an anaerobic batch culture. Moreover, MK or DHNA production was affected by the lactose feeding rate; this suggests that lactose metabolism participates in the syntheses of these products. On the other hand, accumulation of propionate was found to inhibit DHNA production in the fed-batch culture. Based on the fact that ET-3 increases DHNA production in an aerobic culture by consuming propionate, we carried out a cultivation experiment in which an anaerobic fed-batch culture was switched to an anaerobic batch culture and found that the DHNA production was increased to a greater extent than the DHNA production in an anaerobic fed-batch culture. These results suggest that DHNA production by ET-3 is markedly influenced by carbon source limitation and the oxygen supply.
Furuichi
Keisuke
K
Food Technology Research Institute, Meiji Dairies Corporation, 540 Naruda, Odawara, Kanagawa 250-0862, Japan. keisuke_furuichi@meiji-milk.com
Katakura
Yoshio
Y
Ninomiya
Kazuaki
K
Shioya
Suteaki
S
D000693:Anaerobiosis; D002244:Carbon / Q000378:metabolism; D004791:Enzyme Inhibitors / Q000494:pharmacology; D005285:Fermentation; D007785:Lactose / Q000378:metabolism*; D009284:Naphthols / Q000378:metabolism*; D010100:Oxygen / Q000378:metabolism; D011422:Propionates / Q000494:pharmacology; D011424:Propionibacterium / Q000378:metabolism*; D024482:Vitamin K 2 / Q000378:metabolism
D004791:Enzyme Inhibitors; D009284:Naphthols; D011422:Propionates; D024482:Vitamin K 2; C024023:1,4-dihydroxy-2-naphthoic acid; D002244:Carbon; D007785:Lactose; C029658:propionic acid; D010100:Oxygen