Research Institute for Creating the Future, Fuji Oil Holdings Inc., 4-3 Kinunodai, Tsukubamirai-shi, Ibaraki, 300-2497, Japan.
Biomedical Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), 1-8-31 Midorigaoka, Ikeda, Osaka, Japan.
Arch Microbiol. 2023 Aug 18;205(9):309. doi: 10.1007/s00203-023-03655-0.
Lipases (EC 3.1.1.3) are enzymes used in the oils and fats industries to modify the physicochemical properties of triacylglycerol (TAG). Lipase-catalyzed interesterification at high temperatures is an effective method for modifying the physicochemical properties of TAG. The lipase from Burkholderia plantarii (BpL) exhibits excellent catalytic activity for non-regiospecific interesterification at high temperatures, with depressed lipase hydrolytic activity. The detailed catalytic mechanism for reactions involving catalytic residues has not been elucidated because of the lack of a conventional method for estimating interesterification activity. We used our original water-in-oil emulsion system to estimate the interesterification activity of lipases. BpL showed 10% hydrolytic and 140% interesterification activities compared to the lipase from Burkholderia cepacia, which has a high sequence homology with BpL. By comparing the sequence and crystal structure data of the lipases, we clarified that two amino acids near the active center are one of the factors controlling the hydrolytic and interesterification activities of the enzyme.
脂肪酶（EC 3.1.1.3）在油脂工业中被用于修饰三酰基甘油（TAG）的物理化学性质。脂肪酶催化的高温酯交换反应是一种有效修饰 TAG 物理化学性质的方法。来自伯克霍尔德氏菌（Burkholderia plantarii）（BpL）的脂肪酶在高温下表现出优异的非区域特异性酯交换反应催化活性，同时抑制脂肪酶的水解活性。由于缺乏估计酯交换活性的常规方法，涉及催化残基的详细催化机制尚未阐明。我们使用我们原始的油包水乳状液体系来估计脂肪酶的酯交换活性。与具有高序列同源性的伯克霍尔德氏菌（Burkholderia cepacia）来源的脂肪酶相比，BpL 具有 10%的水解活性和 140%的酯交换活性。通过比较脂肪酶的序列和晶体结构数据，我们阐明了靠近活性中心的两个氨基酸是控制酶的水解和酯交换活性的因素之一。
