N-糖蛋白去糖基化酶(PNGase)的研究进展

Research Progress of The Peptide:N-Glycanase(PNGase)

N-糖蛋白去糖基化酶(PNGase)是一种广泛存在于真菌、植物、哺乳动物中的去糖基化酶,可以水解N-糖蛋白或N-糖肽上天冬酰胺与寡糖链连接的化学键,并释放出完整的N-寡糖。PNGase在生物体内参与蛋白质降解、器官发育、个体生长等过程。人PNGase基因功能缺陷会导致先天性去糖基化障碍,小鼠PNGase缺陷会导致胚胎致死性,线虫PNGase缺陷使其寿命下降。本文对PNGase在不同物种的分布、蛋白质结构、酶学功能及生物学功能进行阐述,为PNGase的生理病理功能及致病机制的基础研究提供思路,为PNGase作为糖生物学工具酶或药物开发的创新应用研究奠定基础。

Peptide:N-glycanase(PNGase)is a deglycosylation enzyme widely presented in fungi,plants,mammals and other eukaryotics.Only two bacterial PNGase have being isolated(PNGase F and PNGase F-II)thusfar,and both are used widely as research tools in glycomics.PNGase catalyzed the hydrolysis of the amide bond between N-acetylglucosamine and an Asn residue on an N-glycoprotein,generating a de-N-glycosylated protein and a complete N-oligosaccharide.After the reaction,the N-glycosylated Asn residue was converted to Asp.Although it is known that PNGase participates in protein degradation,organ development,individual growth and other key biological processes in organisms,its impacts on health was illustrated only recently.Human PNGase(NGLY1)deficiency could lead to a genetic disease named congenital disorder of deglycosylationNGLY1.A nematode PNGase deficiency could reduce its life span.Its defects in mice could be embryonic lethal.This article describes the distribution,protein structure,and biological function of PNGase in different species.It can serve as an important information resource to support basic research for PNGase mechanism and innovative study for PNGase applications.