摘要
苯丙氨酸解氨酶(PAL)是植物体内次级代谢的关键酶和限速酶,在果实机械损伤、组织褐变、抵抗逆境等方面具有重要的生理作用。采用冰浴研磨、硫酸铵分级沉淀、DE-52柱层析等方法,对库车小白杏果实中的苯丙氨酸解氨酶进行分离纯化,并对其酶学特性展开研究。结果表明:库车小白杏果实苯丙氨酸解氨酶纯化倍数为4.703,蛋白质得率为0.20%,酶得率为0.95%,纯化后的酶经SDS-PAGE凝胶电泳为单一蛋白带,酶亚基分子质量为51.4 k Da。PAL在硼酸缓冲液中最适p H=8.0、8.9,在Tris-HCl缓冲液中最适p H=8.9;PAL最适反应温度为40℃,对高温有一定的耐受性;最适底物浓度为0.02 mol/L,其米氏常数Km=1.326×10-2mol/L。
PAL,the first and rate-limited key enzyme in secondary metabolism of plants,plays important roles in mechanical damage,tissue browning and resistance to adversity. In this paper,ice rubbing,saturation of ammonium sulfate grade deposition,and DE-52 anion exchange chromatography were employed to isolate and predicate PAL from Kuqa apricot fruit and its enzymatic properties were also studied. The results showed that the purification multiple was 4.703. The protein and PAL yield were 0.20% and 0.95% respectively. The subunit molecular weight was 51.4 k Da analyzed by SDS-PAGE. The optimal p H ranges of PAL in boric acid buffer were 8.0 and 8.9. In addition,the optimum p H in Tris-HCl buffer was 8.9.The optimum temperature was 40 ℃;the optimum substrate concentration of PAL was 0.02 mol/L;values of Kmwas 1.326 ×10^-2mol/L.The results revealed the properties of PAL in Kuqa apricot fruit and provided theoretical basis for improving fruit storage.
出处
《河南工业大学学报（自然科学版）》
CAS
北大核心
2016年第4期74-78,共5页
Journal of Henan University of Technology：Natural Science Edition
基金
塔里木大学校长基金项目(TDZKSS201203)
南疆特色农产品深加工兵团重点实验室项目(AP1501)
关键词
库车小白杏
苯丙氨酸解氨酶
分离纯化
酶学特性
Kuqa apricot
phenylalanine ammonia-lyase
separation and purification
enzymatic property
