Effects of Acidic Fermentation Products and Culture pH on the Maintenance Energy of Clostridium acetobutylicum

산성 발효 산물과 배양 pH가 Clostridium acetobutylicum의 유지 에너지에 미치는 영향

In order to elucidate the acid tolerance mechanism of Clostridium acetobutylicum against organic acid, the maintenance energy with added butyrate at different pH was determined. Maintenance coeffecient in acidogenic chemostat was higher at pH 6.5 than at pH 5.5 showing that this organism is an acidophile. The addition of butyrate at pH 5.5 and different dilution rate caused linear decrease of the cell concentration though $Y_{ATP}$ did not decrease with increasing undissociated organic acid. $Y_{ATP}$ decreased by increasing the concentration of undissociated organic acid at pH 5.0 by the addition of butyrate. From these results it is hypothesized that the ATP conaumption for pH stat of acidophile C. acetobutylicum is increased at the circumstance with over 30mM of undissociated organic acid.cid.