摘要
[目的]提高乳酸乳球工程菌表达L-苯丙氨酸解氨酶的水平。[方法]对培养基种类、接种量、培养温度、诱导剂浓度、磷酸甘油二钠浓度等因素进行了优化。[结果]使用DifcoTMM17 Broth培养基培养乳酸乳球菌时,L-苯丙氨酸解氨酶表达活性最高;磷酸甘油二钠对L-苯丙氨酸解氨酶表达活性有较大影响,可提高活性93.8%。通过正交试验,得到PAL最佳表达条件为接种量2.0%,培养温度30℃,磷酸甘油二钠浓度2.0%,诱导剂浓度10.0μg/L。PAL表达酶活可达3.05 IU/ml。[结论]在发酵扩大培养中优化了L-苯丙氨酸解氨酶在乳酸乳球菌中的表达条件,为今后生产及应用提供参考。
[Objective] In order to improve the level of L-phenylalanine ammonialyase expression in Lactococcus lactis.[Method] The kinds of culture medium,inoculum concentration,incubation temperature,inducer concentration,two sodium glycerophosphate concentration were optimized. [Results] The cultured L.lactis medium using DifcoTM M17 Broth,L-phenylalanine ammonia lyase activity is highest; two sodium glycerophosphate on L-phenylalanine ammonialyase expression significantly affected the enzyme activity,can improve the activity of 93.8％.Through the orthogonal experiment,the optimal conditions for PAL expression were inoculum concentration 2.0％,incubation temperature 30 ℃,two sodium glycerophosphate concentration 2.0％,inducer concentration 10.0 μg/L.The expression of PAL enzyme activity was 3.05 IU/ml.[Conclusion] The study optimized expression condition of L-phenylalanine ammonialyase in Lactococcus lacti,and provided a reference for future production and application.
出处
《安徽农业科学》
CAS
2014年第24期8092-8094,8098,共4页
Journal of Anhui Agricultural Sciences
基金
广州市民生科技重大专项(201300000067
201300000068)
关键词
乳酸乳球菌
L-苯丙氨酸解氨酶
工艺优化
Lactococcus lactis
L-phenylalanine ammonia-lyase
Process optimization
