【摘要】 考察了蜂房哈夫尼菌(H.alveiAS1.1009)的L-赖氨酸脱羧酶对L-赖氨酸的脱羧作用,分析了培养基、温度、pH、激活剂等因素对酶活力的影响。实验结果表明,最适培养基成分为:ρ(蔗糖)=20 g/L、ρ(玉米浆)=20g/L、ρ(酵母膏)=5 g/L、ρ(牛肉膏)=3 g/L、ρ(蛋白胨)=10 g/L、ρ(氯化钠)=5 g/L、ρ(硫酸铵)=2 g/L、ρ(维生素B6)=5 g/L和ρ(L-赖氨酸)=5 g/L,100 mL发酵液中接种量为5 mL液体菌种。最佳转化工艺条件为:转化体系温度35℃、pH=5.0,ρ(菌体)=10 g/L,ρ(吐温-80)=0.15 g/L。L-赖氨酸脱羧酶在最适发酵和转化条件下比酶活可达7 984.43 U,底物转化率可达70%。更多还原

【Abstract】 L-Lysine can be converted to cadaverine with lysine decarboxylase which is found in Hafnia alvei AS 1.1009.Factors affecting the enzymatic activity were studied.The optimum fermentation medium consists of ρ（saccharose）=20 g/L,ρ（corn steep liquor）=20 g/L,ρ（yeast extract）=5 g/L,ρ（beef extract）=3 g/L,ρ（peptone）=10 g/L,ρ（NaCl）=5 g/L,ρ（（NH₄）₂SO₄）=2 g/L,ρ（vitamin B₆）=5 g/L and ρ（L-lysine）=5 g/L.5 mL liquid bacteria was inoculated in 100 mL zymotic fluid.The optimal fermentation conditions are temperature 35 ℃,initial pH of the buffer 5.0,ρ（bacterium）=10 g/L and ρ（Tween-80）=0.15 g/L.Enzymatic activity can rise to（7 984.43） U and conversion of the substrate reaches 70%.更多还原