Citation

Gao L, Shi Y, Zhang E, You J, Han J, Su X, Han S. Anal. Chem. 2022; 94(27): 9903-9910.

Copyright

(Copyright © 2022, American Chemical Society)

DOI

10.1021/acs.analchem.2c01892

PMID

unavailable

Abstract

Lysosomal rupture engaged in diverse diseases remains poorly discerned from lysosomal membrane permeabilization (LMP). We herein reported biocapture-directed chemical labeling (BCCL) for the discern of lysosomal rupture by tracking the release of optically labeled cathepsins from damaged lysosomes into the cytosol. BCCL entails covalent anchoring of an azide-tagged suicide substrate (Epo-LeuTyrAz) to the enzyme active site and bioorthogonal ligation of the introduced azide with DBCORC, a ratiometric sensor featuring an acidity-reporting red emissive X-rhodamine-lactam (ROX), blue emissive coumarin (CM) inert to pH, and DBCO reactive to azide. Aided with fluorescein isocyanate-labeled sialic acid (FITC-Sia), a probe remained in pH-elevated lysosomes but dissipated from LMP+lysosomes, BCCL enables optical discern of four states of lysosomes: ruptured lysosomes (blue in cytosol), LMP+lysosomes (blue in lysosomes), pH-elevated lysosomes (blue and green in lysosomes), and physiological lysosomes (blue, green and red in lysosomes). This approach could find applicability to study lysosome rupture over LMP in diseases and to evaluate lysosome rupture-inducing drugs. © 2022 American Chemical Society. All rights reserved.

Language: en

Keywords

Silicon; pH; Enzyme active sites; Chemical labeling; Covalent anchoring; Cytosols; Lysosomal membranes; Membrane permeabilization; Ratiometric sensors; Red emissive; Rhodamine; Stressed state