摘要
本文利用正交实验方法,对重组降血压肽基因工程菌细胞破碎所得上清液中的融合蛋白GST-AHP,进行亲和层析吸附上柱条件研究。在此基础上,借助高效液相色谱对融合蛋白凝血酶酶切条件进行了研究,并对此分离条件下所得的降血压肽段的体外生物学活性进行初步确定。实验表明,基因工程菌细胞破碎上清液中的融合蛋白GST-AHP进行亲和吸附的最佳上柱条件为上柱量为4mg/mL,上柱流速为1.5mL/min,上柱1次,此条件下融合蛋白的吸附量达3.86mg/mL,洗脱后其回收率达96.5%;凝血酶酶切的最佳工艺条件为1mgGST-AHP融合蛋白添加凝血酶15U,22℃酶切8h,此条件下可得降血压肽段102μg。分离纯化所得降血压肽段的体外生物学活性良好。
The preparation of AHP from recombinant E.coli BL21 by affinity chromatography and thrombin mediated cleavage was studied through orthogonal experiment. RP-HPLC was used to detect the antihypertensive peptides in AHP. The optimum loading quantity of sample and flow rate were 4mg (GST-AHP)/mL(medium bed) andl.5mL/min, respectively, under which, the absorption capacity of fusion protein was 3.86mg/mL (medium bed) with a recovery rate of 96.5%. The optimum cleavage conditions of fusion protein by thrombin were as follows: thrombin dosage of 15 U/mg GST, reaction time of 8h and temperature of 22℃, under which 102μg of AHP could be obtained using lmg GST-AHP. In addition, bioactivity of recombinant AHP was studied. The obtained AHP showed high bioactivity in vitro with IC50 and Km of 4.6 μmol/L and 1.95 mmol/L, respectively.
出处
《现代食品科技》
EI
CAS
2008年第1期55-58,共4页
Modern Food Science and Technology
关键词
降血压肽
亲和层析
融合蛋白
凝血酶
antihypertensive peptides
affinity chromatography
fusion protein
thrombin