Chemoenzymatic Assembly of Bacterial Glycoconjugates for Site-Specific Orthogonal Labeling

The cell surfaces of bacteria are replete with diverse glycoconjugates that play pivotal roles in determining how bacteria interact with the environment and the hosts that they colonize. Studies to advance our understanding of these interactions rely on the availability of chemically defined glycoc...

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Bibliographic Details
Main Authors: Lukose, Vinita, Whitworth, Garrett, Guan, Ziqiang, Imperiali, Barbara
Other Authors: Massachusetts Institute of Technology. Department of Biology
Format: Article
Language:en_US
Published: American Chemical Society (ACS) 2017
Online Access:http://hdl.handle.net/1721.1/106952
https://orcid.org/0000-0003-3761-3743
https://orcid.org/0000-0002-5749-7869
Description
Summary:The cell surfaces of bacteria are replete with diverse glycoconjugates that play pivotal roles in determining how bacteria interact with the environment and the hosts that they colonize. Studies to advance our understanding of these interactions rely on the availability of chemically defined glycoconjugates that can be selectively modified under orthogonal reaction conditions to serve as discrete ligands to probe biological interactions, in displayed arrays and as imaging agents. Herein, enzymes in the N-linked protein glycosylation (Pgl) pathway of Campylobacter jejuni are evaluated for their tolerance for azide-modified UDP-sugar substrates, including derivatives of 2,4-diacetamidobacillosamine and N-acetylgalactosamine. In vitro analyses reveal that chemoenzymatic approaches are useful for the preparation of undecaprenol diphosphate-linked glycans and glycopeptides with site-specific introduction of azide functionality for orthogonal labeling at three specific sites in the heptasaccharide glycan. The uniquely modified glycoconjugates represent valuable tools for investigating the roles of C. jejuni cell surface glycoconjugates in host pathogen interactions