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Probing Monotopic Phosphoglycosyl Transferases from Complex Cellular Milieu.

ABSTRACT: Monotopic phosphoglycosyl transferase enzymes (monoPGTs) initiate the assembly of prokaryotic glycoconjugates essential for bacterial survival and proliferation. MonoPGTs belong to an expansive superfamily with a diverse and richly annotated sequence space; however, the biochemical roles of most monoPGTs in glycoconjugate biosynthesis pathways remain elusive. To better understand these critical enzymes, we have implemented activity-based protein profiling (ABPP) probes as protein-centric, membrane protein compatible tools that lay the groundwork for understanding the activity and regulation of the monoPGT superfamily from a cellular proteome. With straightforward gel-based readouts, we demonstrate robust, covalent labeling at the active site of various representative monoPGTs from cell membrane fractions using 3-phenyl-2H-azirine probes.

SUBMITTER: Anderson AJ

PROVIDER: S-EPMC9703085 | biostudies-literature | 2022 Nov

REPOSITORIES: biostudies-literature

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Probing Monotopic Phosphoglycosyl Transferases from Complex Cellular Milieu.

Anderson Alyssa J AJ Seebald Leah M LM Arbour Christine A CA Imperiali Barbara B

ACS chemical biology 20221108 11

Monotopic phosphoglycosyl transferase enzymes (monoPGTs) initiate the assembly of prokaryotic glycoconjugates essential for bacterial survival and proliferation. MonoPGTs belong to an expansive superfamily with a diverse and richly annotated sequence space; however, the biochemical roles of most monoPGTs in glycoconjugate biosynthesis pathways remain elusive. To better understand these critical enzymes, we have implemented activity-based protein profiling (ABPP) probes as protein-centric, membra ...[more]

PMID: 36346917

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