摘要
在含有较高浓度底物反式肉桂酸(trans-cinnamic acid,CA)和氨反应介质中,研究了β-环糊精(β-CD)对红酵母苯丙氨酸解氨酶(Phenylalanine ammonia-lyase,PAL,EC4.3.1.5)催化反应的影响。加入适量β-CD可以克服高浓度CA对PAL活性的抑制作用,显著增加产物L-苯丙氨酸(L-phe)的产量。β-CD最适用量随CA浓度升高而增加,其摩尔数量约为CA用量的1/12—1/4。CA浓度范围为100—200mmol/L时,对β-CD有效浓度范围为6—50mmol/L。
The effects of the host compound β-cyclodextrin(β-CD) on the reaction of L-phenylalanine ammonia-lyase(PAL,EC4. 3.1. 5)in the whole cells of Rhodotorula rubra AS2. 166 ,in the aqueous media of trans-cinnamic acid (CA) and ammonia were investigated. The results showed that the PAL was steabilized significantly to allow the PAL-catalyzed conversion of CA into L-phenylalanine(L-phe) to proceed smoothly in the presence of high concentration of CA when a proper amount of host compound β-CD was added into the above CA media. The optimum amount of β-CD required to overcome the substrate inhibition of PAL activity increased as the' CA concentration level raised, and it was about twelfth to fourth of that of CA(mole). The most effective addition of β-CD in the comversion media ranged from 6 to 50mmol/L when the employed CA concentration ranged form 100 to 250 mmol/L. Both the initial rates of conversion and the final L-phe production in this new biocatalytical media,i. e. ,PAL-β-CD, containing high concentration of CA were much more satisfactory than in the media without. β-CD.
出处
《天然产物研究与开发》
CAS
CSCD
1995年第2期27-33,共7页
Natural Product Research and Development
关键词
苯丙氨酸解氨酶
Β-环糊精
L-phenylalanine ammonia-lyase,enzyme stabilization,substrate inhibition,host compound β-cyclodextrin ,L-phenylalanine
