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A glycal-based photoaffinity probe that enriches sialic acid binding proteins.

ABSTRACT: To identify sialic acid binding proteins from complex proteomes, three photocrosslinking affinity-based probes were constructed using Neu5Ac (5 and 6) and Neu5Ac2en (7) scaffolds. Kinetic inhibition assays and Western blotting revealed the Neu5Ac2en-based 7 to be an effective probe for the labeling of a purified gut microbial sialidase (BDI_2946) and a purified human sialic acid binding protein (hCD33). Additionally, LC-MS/MS affinity-based protein profiling verified the ability of 7 to enrich a low-abundance sialic acid binding protein (complement factor H) from human serum thus validating the utility of this probe in a complex context.

SUBMITTER: Thuy-Boun PS

PROVIDER: S-EPMC6730559 | biostudies-literature | 2019 Sep

REPOSITORIES: biostudies-literature

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A glycal-based photoaffinity probe that enriches sialic acid binding proteins.

Thuy-Boun Peter S PS Wolan Dennis W DW

Bioorganic & medicinal chemistry letters 20190801 18

To identify sialic acid binding proteins from complex proteomes, three photocrosslinking affinity-based probes were constructed using Neu5Ac (5 and 6) and Neu5Ac2en (7) scaffolds. Kinetic inhibition assays and Western blotting revealed the Neu5Ac2en-based 7 to be an effective probe for the labeling of a purified gut microbial sialidase (BDI_2946) and a purified human sialic acid binding protein (hCD33). Additionally, LC-MS/MS affinity-based protein profiling verified the ability of 7 to enrich a ...[more]

PMID: 31387789

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