N-acetyl-D-glucosamine and its dimer are degradation products of chitin waste with great potential in therapeutic and agricultural applications. However, the hydrolysis of insoluble chitin by chitinases remains a major bottleneck. This study investigated the biochemical properties and catalytic mechanisms of PoChi chitinase obtained from Penicillium oxalicum with a focus on enhancing its efficiency during the degradation of insoluble chitin. Recombinant plasmids were engineered to incorporate chitin-binding (ChBD) and/or fibronectin III (FnIII) domains. Notably, PoChi-FnIII-ChBD exhibited the highest substrate affinity (Km = 2.7 mg/mL) and a specific activity of 15.4 U/mg, which surpasses those of previously reported chitinases. These findings highlight the potential of engineered chitinases in advancing industrial biotechnology applications and offer a promising approach to more sustainable chitin waste management.

中文翻译：

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增强不溶性几丁质的降解：设计高效几丁质酶融合酶以实现可持续应用


N-乙酰基-D-氨基葡萄糖及其二聚体是甲壳素废物的降解产物，在治疗和农业应用中具有巨大潜力。然而，几丁质酶对不溶性几丁质的水解仍然是一个主要瓶颈。本研究研究了从草酸青霉中获得的 PoChi 几丁质酶的生化特性和催化机制，重点是提高其在不溶性几丁质降解过程中的效率。重组质粒经过工程改造，掺入几丁质结合 (ChBD) 和/或纤连蛋白 III (FnIII) 结构域。值得注意的是，PoChi-FnIII-ChBD 表现出最高的底物亲和力（Km = 2.7 mg/mL）和 15.4 U/mg 的比活性，超过了之前报道的几丁质酶。这些发现凸显了工程化几丁质酶在推进工业生物技术应用方面的潜力，并为更可持续的几丁质废物管理提供了一种有前途的方法。