College of Biological and Environmental Engineering, Zhejiang University of Technology, Hangzhou 310032, China.
College of Biological and Environmental Engineering, Zhejiang University of Technology, Hangzhou 310032, China.
Carbohydr Polym. 2015 Dec 10;134:151-7. doi: 10.1016/j.carbpol.2015.08.001. Epub 2015 Aug 6.
The Δ4,5 unsaturated uronate (4-deoxy-α-l-threo-hex-4-eno-pyranosyluronic acid) residue is produced through the depolymerization of heparin, heparosan, and heparan sulfate with heparin lyases. The recovery of unsaturated uronate containing products is necessary to prepare low molecular weight heparin (LMWH) from heparin or heparosan. In this study, the gene of Δ4,5 and Δ4,5(Δ20) unsaturated glycuronidase (EC# 3.2.1.56) from Pedobacter heparinus (formerly Flavobacterium heparinum) was cloned into pMAL-c2x plasmid. Its fusion protein with MBP was expressed in Escherichia coli TB1. After purification, Δ4,5 unsaturated glycuronidase was evaluated. The Δ4,5(Δ20) glycuronidase showed excellent activity on the unsaturated bonds of the different depolymerized products from Hep I, Hep II, and Hep III on heparin, heparosan, and heparan sulfate.
Δ4,5 不饱和尿苷酸（4-去氧-α-l-苏式-己-4-烯吡喃糖醛酸）残基通过肝素、硫酸乙酰肝素和肝素裂解酶的解聚产生。为了从肝素或硫酸乙酰肝素制备低分子量肝素（LMWH），有必要回收含有不饱和尿苷酸的产物。在这项研究中，来自 Pedobacter heparinus（以前称为 Flavobacterium heparinum）的 Δ4,5 和 Δ4,5(Δ20) 不饱和糖醛酸酶（EC# 3.2.1.56）的基因被克隆到 pMAL-c2x 质粒中。其与 MBP 的融合蛋白在大肠杆菌 TB1 中表达。纯化后，评估了 Δ4,5 不饱和糖醛酸酶。Δ4,5(Δ20) 糖醛酸酶对肝素、硫酸乙酰肝素和肝素硫酸中 Hep I、Hep II 和 Hep III 不同解聚产物的不饱和键表现出优异的活性。
