School of Marine Sciences and Fisheries, Jiangsu Ocean University, Lianyungang, Jiangsu Province, People's Republic of China.
Prep Biochem Biotechnol. 2023;53(7):816-826. doi: 10.1080/10826068.2022.2145611. Epub 2022 Nov 18.
A novel uricase producing marine bacterium alkaAU was isolated and identified. The 16S rDNA and the uricase coding gene were sequenced, analyzed and submitted to GenBank. The uricase from alkaAU (PFU) was purified, determined to be 58.87 kDa, and conjugated with carboxymethyl chitosan (CMCS) by ionic gelation. CMCS conjugation had no effect on the optimum pH of PFU but decreased the optimum temperature by 10 °C. CMCS conjugation increased the specific activity of PFU by 53% at the human body temperature (37 °C) and small intestine's pH (pH 6.8). Uricase thermostabilizing ability of CMCS was significant in the range of 37-80 °C but not at lower temperatures. For improvement of the pH stability of PFU, CMCS was more effective at pHs 3-5 than pHs 6-11. CMCS increased the half-life of PFU against artificial intestinal fluid by 1.5 folds, which demonstrated the potential capability of CMCS-PFU for oral administration.
从海洋中分离鉴定到一株产尿酸酶的新的海洋细菌 alkaAU。对其 16S rDNA 序列和尿酸酶编码基因进行了测序、分析，并提交至 GenBank。从 alkaAU 中分离纯化的尿酸酶（PFU）分子量为 58.87 kDa，并用离子凝胶法将其与羧甲基壳聚糖（CMCS）偶联。CMCS 偶联对 PFU 的最适 pH 没有影响，但将最适温度降低了 10°C。CMCS 偶联使 PFU 在人体温度（37°C）和小肠 pH（pH6.8）下的比活性提高了 53%。CMCS 使 PFU 在 37-80°C 范围内的热稳定性显著提高，但在较低温度下没有效果。为了提高 PFU 的 pH 稳定性，CMCS 在 pH3-5 时比在 pH6-11 时更有效。CMCS 使 PFU 在人工肠液中的半衰期延长了 1.5 倍，这表明 CMCS-PFU 具有口服给药的潜力。
