Jiangsu Key Laboratory of Marine Bioresources and Environment/Jiangsu Key Laboratory of Marine Biotechnology, Jiangsu Ocean University, Lianyungang, 222005, China; Co-Innovation Center of Jiangsu Marine Bio-industry Technology, Jiangsu Ocean University, Lianyungang, 222005, China.
Jiangsu Key Laboratory of Marine Bioresources and Environment/Jiangsu Key Laboratory of Marine Biotechnology, Jiangsu Ocean University, Lianyungang, 222005, China; Co-Innovation Center of Jiangsu Marine Bio-industry Technology, Jiangsu Ocean University, Lianyungang, 222005, China; Collaborative Innovation Center of Modern Biological Manufacturing, Anhui University, Hefei, 230039, China.
Protein Expr Purif. 2020 Oct;174:105678. doi: 10.1016/j.pep.2020.105678. Epub 2020 May 21.
Dental plaque is a high-incidence health concern, and it is caused by Streptococcus mutans. Dextranase can specifically hydrolyze ɑ-1,6-glycosidic linkages in dextran. It is commonly used in the sugar industry, in the production of plasma substitutes, and the treatment and prevention of dental plaque. In this research work, we successfully cloned and expressed a cold-adapted dextranase from marine bacteria Catenovulum sp. DP03 in Escherichia coli. The recombinant dextranase named Cadex2870 contained a 2511 bp intact open reading frame and encoded 836 amino acids. The expression condition of recombinant strain was 0.1 mM isopropylthio-galactoside (IPTG), and the reduced temperature was 16 °C. The purified enzyme activity was 16.2 U/mg. The optimal temperature and pH of Cadex2870 were 45 °C and pH 8, and it also had catalytic activity at 0 °C. The hydrolysates of Cadex2870 hydrolysis Dextran T70 are maltose, maltotetraose, maltopentose, maltoheptaose and higher molecular weight maltooligosaccharides. Interestingly, 0.5% sodium benzoate, 2% xylitol, 0.5% sodium fluoride, 5% propanediol, 5% glycerin and 2% sorbitol can enhance stability Cadex2870, which are additives in mouthwashes. Additionally, Cadex2870 reduced the formation of dental plaque and effectively degraded formed plaque. Therefore, Cadex2870 shows great promise in commercial applications.
牙菌斑是一种高发的健康问题，它是由变形链球菌引起的。葡聚糖酶可以特异性地水解葡聚糖中的α-1,6-糖苷键。它在制糖工业、血浆代用品的生产以及牙菌斑的治疗和预防中被广泛应用。在这项研究工作中，我们成功地从海洋细菌 Catenovulum sp. DP03 中克隆并表达了一种冷适应的葡聚糖酶。该重组葡聚糖酶命名为 Cadex2870，包含一个 2511 bp 的完整开放阅读框，编码 836 个氨基酸。重组菌株的表达条件为 0.1 mM 的异丙基硫代-β-D-半乳糖苷（IPTG），降低温度为 16°C。纯化后的酶活为 16.2 U/mg。Cadex2870 的最适温度和 pH 值分别为 45°C 和 pH 8，它在 0°C 下也具有催化活性。Cadex2870 水解葡聚糖 T70 的水解产物为麦芽糖、麦芽四糖、麦芽五糖、麦芽七糖和更高分子量的麦芽寡糖。有趣的是，0.5%的苯甲酸钠、2%的木糖醇、0.5%的氟化钠、5%的 1,2-丙二醇、5%的甘油和 2%的山梨醇可以增强 Cadex2870 的稳定性，这些都是漱口水的添加剂。此外，Cadex2870 减少了牙菌斑的形成，并有效地降解了已形成的菌斑。因此，Cadex2870 在商业应用中具有很大的潜力。
Zotero 插件