环糊精糖基转移酶JSL-1的鉴定及功能研究  

Identification and Functional Study of Cyclodextrin Glycosyltransferase JSL-1

作　　者：李茹 丁欣杰 商金海 秦林雪 魏铠 王月 李攀 LI Ru;DING Xinjie;SHANG Jinhai;QIN Linxue;WEI Kai;WANG Yue;LI Pan(School of Pharmacy,Liaocheng University,Liaocheng 252059,China)

机构地区：[1]聊城大学药学院,山东聊城252059

出　　处：《聊城大学学报（自然科学版）》2024年第2期80-88,共9页Journal of Liaocheng University:Natural Science Edition

基　　金：国家自然科学基金项目(32001982);山东省自然科学基金资助项目(ZR2021MC062)资助。

摘　　要：环糊精糖基转移酶(Cyclodextrin glycosyltransferase,CGTase)可以通过环化反应催化淀粉及其衍生物生成环糊精(Cyclodextrin,CDs)。研究通过基因工程技术手段,成功获得东洋芽孢杆菌Bacillus toyonensi s P18中环糊精糖基转移酶JSL-1蛋白,探讨其产物特异性及酶学性质。同时,将JSL-1基因超表达到日本晴水稻中,研究环糊精糖基转移酶JSL-1对水稻淀粉质量的影响。结果表明,JSL-1主要催化淀粉生成α-CD,其最适反应pH和最适反应温度分别是8.0和50℃。随着JSL-1表达水平的增加,水稻中直链淀粉含量及老化程度下降,透光率及冻融稳定性增加,有利于提高水稻的食味品质以及外观品质等特性。总之,对环糊精糖基转移酶JSL-1的研究有利于环糊精生产工艺的改良以及水稻品质的提升。Cyclodextrin glycosyltransferase(CGTase)can catalyze starch and its derivatives to produce cyclodextrin(CDs)through cyclization reaction.In this study,the cyclodextrin glycosyltransferase JSL-1 protein in Bacillus toyonensis P18 was successfully obtained by means of genetic engineering technology to explore its product specificity and enzymatic properties.Meanwhile,the JSL-1 gene was overexpressed into Nipponbare rice to study the effect of cyclodextrin glycosyltransferase JSL-1 on rice starch quality.The results showed that JSL-1 mainly catalyzed starch to produceα-CD,and its optimum reaction pH and temperature were 8.0 and 50℃,respectively.With the increase of JSL-1 expression level,the amylose content and aging degree in rice decreased,and the light transmittance and freeze-thaw stability increased,which was beneficial to improve the eating quality and appearance quality of rice.In conclusion,the study of cyclodextrin glycosyltransferase JSL-1 is beneficial to the improvement of cyclodextrin production technology and the improvement of rice quality.

关 键 词：环糊精糖基转移酶 产物特异性 酶学性质 转基因水稻 淀粉特性 

分 类 号：Q943.2[生物学—植物学]