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bioRxiv · 10.1101/2021.06.15.448502

A self-immolative linker for heparanase activatable probe

Schleyer, K. A.·Liu, J.·Wang, Z.·Cui, L.
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Abstract

Substrate-based probes utilize known substrate specificity parameters to create a probe that can be activated by a target enzyme. In developing probes for heparanase, an endo-{beta}-glucuronidase, we previously reported that small, inactive substrate-based probes could be electronically tuned by incorporating electron-withdrawing atoms on the aromatic aglycone fluorophore, ortho- to the cleaved glycosidic bond. However, the installation of electron-withdrawing groups directly onto established fluorophores or other reporters complicates the synthesis of new heparanase probes. In this work we report a new design strategy to expand the toolkit of heparanase imaging probes, in which the installation of an electronically tuned benzyl alcohol linker restored the activity of a previously inactive heparanase probe using 4-methylumbelliferone as the fluorescent reporter, suggesting such a linker can provide a scaffold for facile development of activatable heparanase probes bearing a variety of imaging moieties.

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Schleyer, K. A., Liu, J., Wang, Z., Cui, L.. 2021-06-15. A self-immolative linker for heparanase activatable probe. https://doi.org/10.1101/2021.06.15.448502

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