Marine Science and Technology College, Zhejiang Ocean University, Zhoushan 316000, China.
Third Institute of Oceanography, Ministry of Natural Resources, Xiamen 361000, China.
Mar Drugs. 2022 Nov 1;20(11):692. doi: 10.3390/md20110692.
Up until now, the characterizations of GH50 agarases from species have rarely been reported compared to GH16 agarases. In this study, a deep-sea strain, WPAGA4, was isolated and identified as due to the maximum similarity of its 16S rRNA gene sequence, the values of its average nucleotide identity, and through digital DNA-DNA hybridization. Two circular chromosomes in WPAGA4 were assembled. A total of 4561 coding genes, 37 rRNA, 131 tRNA, and 59 other non-coding RNA genes were predicted in the genome of WPAGA4. An agarase gene belonging to the GH50 family was annotated in the genome sequence and expressed in cells. The optimum temperature and pH of the recombinant Aga3420 (rAga3420) were 40 °C and 7.0, respectively. Neoagarobiose (NA2) was the only product during the degradation process of agarose by rAga3420. rAga3420 had a favorable stability following incubation at 10-30 °C for 50 min. The , , and values of rAga3420 were 2.8 mg/mL, 78.1 U/mg, and 376.9 s, respectively. rAga3420 displayed cold-adapted properties as 59.7% and 41.2% of the relative activity remained at 10 3 °C and 0 °C, respectively. This property ensured WPAGA4 could degrade and metabolize the agarose in cold deep-sea environments and enables rAga3420 to be an appropriate industrial enzyme for NA2 production, with industrial potential in medical and cosmetic fields.
迄今为止，与 GH16 琼脂酶相比，来自 物种的 GH50 琼脂酶的特性很少被报道。在本研究中，由于其 16S rRNA 基因序列的最大相似性、平均核苷酸同一性值以及通过数字 DNA-DNA 杂交，分离并鉴定深海菌株 WPAGA4 为 。WPAGA4 有两条圆形染色体。在 WPAGA4 的基因组中总共预测到 4561 个编码基因、37 个 rRNA、131 个 tRNA 和 59 个其他非编码 RNA 基因。在基因组序列中注释了属于 GH50 家族的琼脂酶基因，并在 细胞中表达。重组 Aga3420（rAga3420）的最适温度和 pH 分别为 40°C 和 7.0。在 rAga3420 降解琼脂糖的过程中，只有 neoagarobiose（NA2）是产物。rAga3420 在 10-30°C 孵育 50 分钟后具有良好的稳定性。rAga3420 的 、 和 值分别为 2.8mg/mL、78.1U/mg 和 376.9s。rAga3420 表现出冷适应特性，在 10 3 °C 和 0°C 下相对活性分别保持 59.7%和 41.2%。该特性确保 WPAGA4 能够在寒冷的深海环境中降解和代谢琼脂糖，并使 rAga3420 成为生产 NA2 的合适工业酶，在医学和化妆品领域具有工业潜力。
