SORTASE-LABELED CLOSTRIDIA NEUROTOXINS Russian patent published in 2023 - IPC C07K14/33 C07K19/00 C12N9/52 C12N15/09 A61K49/00 

FIELD: biotechnology.

SUBSTANCE: method of obtaining a labeled polypeptide, a labeled polypeptide for its visualization, and a method of determining at least the internalization and/or intracellular transport of the labeled polypeptide are proposed. A polypeptide containing an acceptor site for sortase or a donor site for sortase, a non-cytotoxic protease containing the L-chain of clostridial neurotoxin, or its proteolytically inactive mutant, a targeting part (TP) that is capable of binding to a binding site on a target cell, and a translocation domain are obtained. The polypeptide is incubated with sortase and a labeled substrate containing a sortase donor site or an acceptor site for sortase, respectively, and a conjugated detectable label. A labeled polypeptide that does not have reduced potency compared to the equivalent unlabeled polypeptide and/or exhibits similar cell binding, translocation, and cleavage of the SNARE protein to the equivalent unlabeled polypeptid are obtained.

EFFECT: visualization of cell binding, translocation and/or cleavage of the SNARE protein using a cell-based assay or in vivo.

15 cl, 6 dwg, 5 ex