Lee Hye-Won, Jeon Hye-Yeon, Choi Hye-Jeong, Kim Na-Ri, Choung Woo-Jae, Koo Ye-Seul, Ko Dam-Seul, You SangGuan, Shim Jae-Hoon
Department of Food Science and Nutrition and Center for Aging and Health Care, Hallym University , Hallymdaehak-gil 1, Chuncheon, Gangwon-do 200-702, South Korea.
Department of Marine Food Science and Technology, Gangneung-Wonju National University , 120 Gangneung Daehangno, Gangneung, Gangwon 210-702, South Korea.
J Agric Food Chem. 2016 Apr 6;64(13):2709-18. doi: 10.1021/acs.jafc.5b05904. Epub 2016 Mar 24.
In this study, a novel α-amylase was cloned from Bifidobacterium longum and named BiLA. The enzyme exhibited optimal activity at 20 °C and a pH value of 5.0. Kinetic analysis using various carbohydrate substrates revealed that BiLA had the highest k(cat/)K(m) value for amylose. Interestingly, analysis of the enzymatic reaction products demonstrated that BiLA specifically catalyzed the hydrolysis of oligosaccharides and starches up to G5 from the nonreducing ends. To determine whether BiLA can be used to generate slowly digestible starch (SDS), starch was treated with BiLA, and the kinetic parameters were analyzed using porcine pancreatic α-amylase (PPA) and amyloglucosidase (AMG). Compared to normal starch, BiLA-treated starch showed lower k(cat)/K(m) values with PPA and AMG, suggesting that BiLA is a potential candidate for the production of SDS.
在本研究中，从长双歧杆菌中克隆出一种新型α-淀粉酶，并将其命名为BiLA。该酶在20℃和pH值5.0时表现出最佳活性。使用各种碳水化合物底物进行的动力学分析表明，BiLA对直链淀粉的k(cat)/K(m)值最高。有趣的是，对酶促反应产物的分析表明，BiLA特异性催化寡糖和淀粉从非还原端水解至G5。为了确定BiLA是否可用于生成慢消化淀粉（SDS），用BiLA处理淀粉，并使用猪胰α-淀粉酶（PPA）和淀粉葡糖苷酶（AMG）分析动力学参数。与正常淀粉相比，经BiLA处理的淀粉在PPA和AMG作用下的k(cat)/K(m)值较低，这表明BiLA是生产SDS的潜在候选物。
