Z-Arg-Leu-Arg-Gly-Gly-AMC

Z-Arg-Leu-Arg-Gly-Gly-AMC (Z-RLRGG-AMC) is a peptide substrate of SARS-CoV papain (PLpro), where RLRGG is the C-terminal sequence of ubiquitin (Ub)^{[1, 2]}. The maximum excitation/emission wavelengths of Z-Arg-Leu-Arg-Gly-Gly-AMC are 340/450 nm, respectively ^[3].

Z-Arg-Leu-Arg-Gly-Gly-AMC is primarily used to study protease activity. By measuring the fluorescence intensity of released 7-amino-4-methylcoumarin (AMC), the catalytic activity of proteases can be assessed^[4]. Z-Arg-Leu-Arg-Gly-Gly-AMC consists of a pentapeptide sequence linked to the fluorescent group AMC. The "Z" denotes the benzyloxycarbonyl (Z) protecting group, which is used to protect amino acids from nonspecific reactions ^[5].

References:
[1] Báez-Santos Y M, Mielech A M, Deng X, et al. Catalytic function and substrate specificity of the papain-like protease domain of nsp3 from the Middle East respiratory syndrome coronavirus[J]. Journal of virology, 2014, 88(21): 12511-12527.
[2] Li L, Ma L, Hu Y, et al. Natural biflavones are potent inhibitors against SARS-CoV-2 papain-like protease[J]. Phytochemistry, 2022, 193: 112984.
[3] Fu Z, Huang B, Tang J, et al. The complex structure of GRL0617 and SARS-CoV-2 PLpro reveals a hot spot for antiviral drug discovery[J]. Nature communications, 2021, 12(1): 488.
[4] Wang C, Chen S, Yeo S, et al. Elevated p62/SQSTM1 determines the fate of autophagy-deficient neural stem cells by increasing superoxide[J]. Journal of Cell Biology, 2016, 212(5): 545-560.
[5] Kadereit D, Waldmann H. Enzymatic protecting group techniques[J]. Chemical Reviews, 2001, 101(11): 3367-3396.

Z-Arg-Leu-Arg-Gly-Gly-AMC（Z-RLRGG-AMC）是一种 SARS-CoV 木瓜蛋白酶（PL^pro）的肽底物，RLRGG是泛素（Ub）的C末端序列^{[1, 2]}。Z-Arg-Leu-Arg-Gly-Gly-AMC的最大激发光/发射光波长分别为340/450 nm^[3]。

Z-Arg-Leu-Arg-Gly-Gly-AMC主要用于研究蛋白酶的活性，通过测定7-氨基-4-甲基香豆素（AMC）释放的荧光强度，可以评估蛋白酶的催化活性^[4]。Z-Arg-Leu-Arg-Gly-Gly-AMC由一个五肽序列与荧光基团AMC连接，Z表示苄氧羰基（Z）保护基团，用于保护氨基酸免受非特异性反应^[5]。