摘 要：对GASBD(s)蛋白与不溶性淀粉进行定性分析，结果显示GASBD(s)蛋白展现出很强的淀粉结合特性,GASBD(s)蛋白与不溶性淀粉的结合力随着融合蛋白中GASBD串联重复数的增加而增加。GASBD(s)蛋白与淀粉的结合量随时间变化的实验结果，表明GASBDs蛋白在淀粉粒表面达到最大结合量的时间与GASBD蛋白一样，都为2h。通过吸附等温曲线计算GASBD(s)蛋白与不溶性淀粉间的亲和力，结果发现GASBD2、GASBD3和GASBD4蛋白与不溶性玉米淀粉或马铃薯淀粉的亲和力大约是GASBD蛋白与淀粉亲和力的5、8和10倍，这表明串联重复的GASBDs蛋白在结合淀粉时具有协同效应。80039

毕业论文关键词：重组蛋白，淀粉亲和性，结合曲线，协同效应

Abstract：The affinities of GASBD(s) protein and insoluble starch were analyzed qualitatively , and the results show that the GASBD(s) protein exhibit a strong starch binding property, and the binding force between the GASBD(s) protein and insoluble starch increases with the GASBD tandem repeat number in fusion protein。 The binding capacity of the GASBD(s) protein with time were analyzed。 Experiment results indicate that the time, for which the GASBD(s) protein reaches the maximum binding amount on the surface of starch granules, is 2h。 Affinities between the GASBD(s) protein and the insoluble starch are calculated by measuring adsorption isothermal curve, and it is found that affinities among the GASBD2, GASBD3, and GASBD4 protein and the insoluble corn starch or the insoluble potato starch are appropriate 5, 8, and 10 times the starch affinity of the GASBD protein。 It is concluded that the tandem repeat GASBD(s) protein has a synergistic effect when bound with a starch。

Keywords: recombinant proteins, starch affinity, binding curve, synergistic effect

目   录

1  前言 4

2  实验材料 5

2。1  菌株与质粒 5

2。2  仪器 5

2。3  试剂 5

2。4  培养基 5

3  实验方法 5

3。1  可溶性重组蛋白GASBD(s)的诱导表达 5

3。2  重组蛋白GASBD(s)的纯化 6

3。3  GASBD(s)重组蛋白与玉米淀粉结合的定性分析 6

3。4  GASBD(s)重组蛋白的结合曲线 6

3。5  GASBD(s)重组蛋白的吸附等温曲线 7

4  实验结果 8

4。1  GASBD(s)重组蛋白与淀粉结合的定性分析 8

4。2  GASBD(s)重组蛋白的结合曲线 8

4。3  GASBD(s)重组蛋白的吸附等温曲线 10

结  论 12

参 考 文 献 13

致  谢 15

1  前言

    糖化酶(Glucoamylase, GA) (EC3。2。1。3)通过水解α-1,4糖苷键将β-D-葡萄糖从淀粉及相关底物中释放出来。它们是典型的微生物酶，主要存在于古细菌、细菌和真菌中。黑曲霉糖化酶是具有多个结构域的酶，其淀粉结合结构域(SBD)通过高度糖基化的连接肽与具有(α/α)6-桶构象的催化结构域相连。