Department of Pharmacology, College of Basic Medicine, Qingdao University, Qingdao 266071, China.
Department of Rehabilitation Medicine, Qingdao University, Qingdao 266071, China.
Mar Drugs. 2019 May 24;17(5):308. doi: 10.3390/md17050308.
Alginate oligosaccharides (AOS) show versatile bioactivities. Although various alginate lyases have been characterized, enzymes with special characteristics are still rare. In this study, a polysaccharide lyase family 7 (PL7) alginate lyase-encoding gene, , was cloned from the marine bacterium sp. SY01 and expressed in The purified alginate lyase Aly08, with a molecular weight of 35 kDa, showed a specific activity of 841 U/mg at its optimal pH (pH 8.35) and temperature (45 °C). Aly08 showed good pH-stability, as it remained more than 80% of its initial activity in a wide pH range (4.0-10.0). Aly08 was also a thermo-tolerant enzyme that recovered 70.8% of its initial activity following heat shock treatment for 5 min. This study also demonstrated that Aly08 is a polyG-preferred enzyme. Furthermore, Aly08 degraded alginates into disaccharides and trisaccharides in an endo-manner. Its thermo-tolerance and pH-stable properties make Aly08 a good candidate for further applications.
海藻酸盐寡糖（AOS）表现出多种生物活性。尽管已经对各种海藻酸盐裂解酶进行了表征，但具有特殊特性的酶仍然很少。在这项研究中，从海洋细菌 sp. SY01 中克隆了一种多糖裂解酶家族 7（PL7）的海藻酸盐裂解酶编码基因，并在 中表达。纯化的海藻酸盐裂解酶 Aly08 的分子量为 35 kDa，在最适 pH（pH 8.35）和温度（45°C）下具有 841 U/mg 的比活性。Aly08 具有良好的 pH 稳定性，在较宽的 pH 范围（4.0-10.0）内保持超过初始活性 80%的活性。Aly08 也是一种耐热酶，在 5 分钟的热冲击处理后，其初始活性恢复了 70.8%。本研究还表明，Aly08 是一种优先作用于多聚 G 的酶。此外，Aly08 以内切方式将海藻酸盐降解为二糖和三糖。其耐热性和 pH 稳定性使 Aly08 成为进一步应用的良好候选酶。
