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克雷伯杆菌发酵生产1,3-丙二醇(1,3-PD)的过程中,通过加入表面活性剂可改善细胞通透性,以减少产物和副产物对细胞生长与代谢的抑制作用,从而促进细菌生长和1,3-PD产出.对比研究了吐温-80(Tween-80)、曲拉通X-100(Triton X-100)、壬基酚聚氧乙烯醚-10(OP-10)和十六烷基三甲基溴化铵(CTAB)等对发酵中甘油脱氢酶(GDH)、1,3-丙二醇氧化还原酶(PDOR)和甘油脱水酶(GDHt)等3种关键酶活的影响.实验表明OP-10能较好改善细胞通透性,胞内释放核酸浓度随添加OP-10量的增加有明显提高.低浓度的OP-10对GDH,PDOR活性及细胞生长有较好的促进作用;发酵8～12 h时添加1.0 g·L-1的OP-10可使1,3-PD浓度和摩尔转化率有较大提高.结合透射电镜发现非离子表面活性剂OP-10损伤膜结构,致细胞通透性改变,有利于充分发挥细胞内酶的催化活性,对细菌生长和1,3-丙二醇的合成有较大促进作用.
During the fermentation of Klebsiella to produce 1,3-propanediol (1,3-PD), cell permeability can be improved by adding surfactants to reduce the inhibition of cell growth and metabolism by products and by-products Promoting the growth of bacteria and the production of 1,3-PD.Compared the effects of Tween-80, Triton X-100, OP- 10) and cetyltrimethylammonium bromide (CTAB) on the fermentation of glycerol dehydrogenase (GDH), 1,3-propanediol oxidoreductase (PDOR) and glycerol dehydratase (GDHt) and other three key The results showed that OP-10 could improve the cell permeability and the intracellular release of nucleic acid significantly increased with the addition of OP-10.The effect of low concentration of OP-10 on GDH, PDOR activity and cell growth Had a better promoting effect.It was found that addition of 1.0 g · L-1 OP-10 at 8-12 h could increase the concentration of 1,3-PD and the molar conversion greatly.Under transmission electron microscopy, it was found that non-ionic surfactant OP-10 damage the membrane structure, resulting in changes in cell permeability is conducive to give full play to the catalytic activity of intracellular enzymes on bacterial growth and 1,3-propanediol have a greater role in promoting the synthesis.