School of Life Sciences, Fudan University, Shanghai, 200433, China.
School of Life Sciences, Fudan University, Shanghai, 200433, China.
Biochem Biophys Res Commun. 2024 Nov 5;732:150405. doi: 10.1016/j.bbrc.2024.150405. Epub 2024 Jul 14.
β-Glucosidase is a crucial cellulase, as its activity determines the efficiency of cellulose hydrolysis into glucose. This study addresses the functional and structural characteristics of Thermotoga profunda β-glucosidase (Tp-BGL). Tp-BGL exhibited a K of 0.3798 mM for p-nitrophenyl-β-d-glucopyranoside (pNPGlc) and 4.44 mM for cellobiose, with k/K of 1211.16 and 4.18 s mM, respectively. In addition, Tp-BGL showed significant pH adaptability and thermal stability, with a T of 85.7 °C and retaining >90 % of its activity after incubation at 80 °C for 90 min. The crystal structure of Tp-BGL was resolved at 1.95 Å resolution, and reveals a typical TIM barrel structure. Comparative structural analysis highlighted that the major distinction between Tp-BGL and the other glucosidases lies in their loop regions.
β-葡萄糖苷酶是一种重要的纤维素酶，其活性决定了纤维素水解为葡萄糖的效率。本研究探讨了深海栖热菌β-葡萄糖苷酶（Tp-BGL）的功能和结构特征。Tp-BGL 对 p-硝基苯-β-D-葡萄糖苷（pNPGlc）的 K 为 0.3798 mM，对纤维二糖的 K 为 4.44 mM，k/K 分别为 1211.16 和 4.18 s mM。此外，Tp-BGL 表现出显著的 pH 适应性和热稳定性，T 为 85.7°C，在 80°C 孵育 90 分钟后仍保留>90%的活性。Tp-BGL 的晶体结构分辨率为 1.95 Å，呈现出典型的 TIM 桶结构。比较结构分析表明，Tp-BGL 和其他葡萄糖苷酶之间的主要区别在于它们的环区。
