Department of Biotechnology, Dong-A University, Busan 49315, Republic of Korea.
Department of Agricultural Chemistry and Food Science Technology, Institute of Agriculture & Life Science (IALS), Gyeongsang National University, Jinju, Republic of Korea; Division of Applied Life Science (BK21), Gyeongsang National University, Jinju, Republic of Korea.
Int J Biol Macromol. 2021 Feb 1;169:452-462. doi: 10.1016/j.ijbiomac.2020.12.138. Epub 2020 Dec 21.
Alginate and its derivatives are annually produced approximately 30,000 tons or more and are applied to various industries as they are natural polymers. The global market for alginate and its derivatives has been growing steadily. There is little research compared to other enzymes produced through biomass degradation or modification. An alginate lyase, MtAl138, from Microbulbifer thermotolerans DAU221 was cloned and identified in Escherichia coli BL21 (DE3). MtAl138 contains a highly conserved motif (RTELR, QIH, and YFKAGVYNQ), which indicates that it belongs to the polysaccharide lyase family 7 (PL7). MtAl138, with a molecular weight of 77 kDa worked optimally at 45 °C and pH 7.4. MtAl138 showed twice as much activity as when there was no NaCl when there was between 100 and 600 mM NaCl. Moreover, its activity increased in organic solvents such as benzene, hexane, methanol, and toluene. Based on the thin layer chromatography analyses, MtAl38 is an endo-type enzyme that produces di-, tri-, or tetrasaccharides from polyG and polyM. This study provided that MtAl138 is an endoenzyme that showed outstanding enzymatic activity at concentrated salt solutions and organic solvents, which makes it a reasonably attractive enzyme for use in various industries.
海藻酸盐及其衍生物的年生产量约为 30000 吨甚至更多，由于它们是天然聚合物，因此被应用于各个行业。全球海藻酸盐及其衍生物市场一直在稳步增长。与通过生物质降解或修饰产生的其他酶相比，针对其的研究较少。从嗜热微菌（Microbulbifer thermotolerans）DAU221 中克隆并鉴定了一种海藻酸盐裂解酶 MtAl138，它在大肠杆菌 BL21（DE3）中表达。MtAl138 含有一个高度保守的基序（RTELR、QIH 和 YFKAGVYNQ），表明它属于多糖裂解酶家族 7（PL7）。MtAl138 的分子量为 77 kDa，在 45°C 和 pH 7.4 下具有最佳活性。当存在 100-600 mM NaCl 时，MtAl138 的活性是没有 NaCl 时的两倍。此外，它在苯、己烷、甲醇和甲苯等有机溶剂中的活性也有所提高。根据薄层层析分析，MtAl38 是一种内切酶，可从聚 G 和聚 M 中产生二糖、三糖或四糖。本研究表明 MtAl138 是一种在高盐溶液和有机溶剂中表现出出色酶活性的内切酶，这使其成为各种工业中具有吸引力的酶。
