Glycosaminoglycans (GAGs) and their low-molecular weight derivates have received considerable interest in terms of their potential clinical applications, and display a wide variety of pharmacological and pharmacokinetic properties. Structurally distinct GAG chains can be prepared by enzymatic depolymerization. A variety of bacterial chondroitin sulfate (CS) lyases have been identified, and have been widely used as catalysts in this process. Here, we identified a putative chondroitin AC exolyase gene, AschnAC, from an Arthrobacter sp. strain found in a CS manufacturing workshop. We expressed the enzyme, AsChnAC, recombinantly in Escherichia coli, then purified and characterized it in vitro. The enzyme indeed displayed exolytic cleavage activity toward HA and various CSs. Removing the putative N-terminal secretion signal peptide of AsChnAC improved its expression level in E. coli while maintaining chondroitin AC exolyase activity. This novel catalyst exhibited its optimal activity in the absence of added metal ions. AsChnAC has potential applications in preparation of low-molecular weight GAGs, making it an attractive catalyst for further investigation.

中文翻译：

---

关节杆菌中软骨素AC外切酶的克隆与鉴定 SD-04。

糖胺聚糖（GAG）及其低分子量衍生物在其潜在的临床应用方面已经引起了广泛的关注，并显示出广泛的药理和药代动力学特性。可以通过酶促解聚制备结构上不同的GAG链。已鉴定出多种细菌硫酸软骨素（CS）裂解酶，并已广泛用作该过程的催化剂。在这里，我们从节杆菌属中鉴定了一个假定的软骨素AC外切酶基因AschnAC。CS制造车间中发现的菌株。我们在大肠杆菌中重组表达了酶AsChnAC，然后对其进行了纯化和体外表征。该酶确实显示出对HA和各种CS的放性裂解活性。去除假定的AsChnAC的N末端分泌信号肽可提高其在大肠杆菌中的表达水平，同时保持软骨素AC外切酶活性。这种新型催化剂在不添加金属离子的情况下表现出最佳活性。AsChnAC在制备低分子量GAG中具有潜在的应用，使其成为进一步研究的有吸引力的催化剂。