Institute of Tropical Bioscience and Biotechnology, Hainan Institute for Tropical Agricultural Resources, Chinese Academy of Tropical Agricultural Sciences, Haikou 571101, China.
Hangzhou Watson Biotechnology Co., Ltd., Hangzhou 311400, China.
Mar Drugs. 2024 Sep 10;22(9):414. doi: 10.3390/md22090414.
Alginate lyase is an attractive biocatalyst that can specifically degrade alginate to produce oligosaccharides, showing great potential for industrial and medicinal applications. Herein, an alginate-degrading strain HB236076 was isolated from sp. in Qionghai, Hainan, China. The low 16S rRNA gene sequence identity (<98.4%), ANI value (<71.9%), and dDDH value (<23.9%) clearly indicated that the isolate represented a potential novel species of the genus . The genome contained two chromosomes with lengths of 3,007,948 bp and 874,895 bp, respectively, totaling 3,882,843 bp with a G+C content of 46.5%. Among 3482 genes, 3332 protein-coding genes, 116 tRNA, and 34 rRNA sequences were predicted. Analysis of the amino acid sequences showed that the strain encoded 73 carbohydrate-active enzymes (CAZymes), predicting seven PL7 (Alg1-7) and two PL17 family (Alg8, 9) alginate lyases. The extracellular alginate lyase from strain HB236076 showed the maximum activity at 50 °C and pH 7.0, with over 90% activity measured in the range of 30-60 °C and pH 6.0-10.0, exhibiting a wide range of temperature and pH activities. The enzyme also remained at more than 90% of the original activity at a wide pH range (3.0-9.0) and temperature below 50 °C for more than 2 h, demonstrating significant thermal and pH stabilities. Fe had a good promoting effect on the alginate lyase activity at 10 mM, increasing by 3.5 times. Thin layer chromatography (TLC) and electrospray ionization mass spectrometry (ESI-MS) analyses suggested that alginate lyase in fermentation broth could catalyze sodium alginate to produce disaccharides and trisaccharides, which showed antimicrobial activity against , , , , and . This research provided extended insights into the production mechanism of alginate lyase from sp. HB236076, which was beneficial for further application in the preparation of pH-stable and thermo-stable alginate lyase and alginate oligosaccharides.
海藻酸裂解酶是一种有吸引力的生物催化剂，可特异性地降解海藻酸盐产生寡糖，在工业和医药应用中具有巨大潜力。本文从中国海南琼海的 sp.中分离到一株能降解海藻酸盐的菌株 HB236076。低的 16S rRNA 基因序列同一性(<98.4%)、ANI 值(<71.9%)和 dDDH 值(<23.9%)清楚地表明，该分离株代表了属的一个潜在新种。基因组包含两条染色体，长度分别为 3007948bp 和 874895bp，总长 3882843bp，GC 含量为 46.5%。在 3482 个基因中，预测了 3332 个蛋白编码基因、116 个 tRNA 和 34 个 rRNA 序列。氨基酸序列分析表明，该菌株编码 73 种碳水化合物活性酶 (CAZymes)，预测了 7 种 PL7 (Alg1-7)和 2 种 PL17 家族 (Alg8、9)海藻酸盐裂解酶。菌株 HB236076 的胞外海藻酸盐裂解酶在 50°C 和 pH7.0 下表现出最大活性，在 30-60°C 和 pH6.0-10.0 范围内活性超过 90%，表现出广泛的温度和 pH 活性。该酶在 pH3.0-9.0 范围内和低于 50°C 的温度下保持超过 90%的原始活性超过 2 小时，表现出显著的热和 pH 稳定性。10mM 的 Fe 对海藻酸盐裂解酶活性有很好的促进作用，提高了 3.5 倍。薄层层析 (TLC)和电喷雾电离质谱 (ESI-MS)分析表明，发酵液中的海藻酸盐裂解酶能催化海藻酸钠产生二糖和三糖，对 、 、 、 和 表现出抗菌活性。本研究为进一步了解 sp. HB236076 产生海藻酸裂解酶的机制提供了依据，有利于进一步应用于制备 pH 稳定和热稳定的海藻酸裂解酶和海藻酸盐寡糖。
