Design and Semisynthesis of Biselectrophile-Functionalized Ubiquitin Probes To Investigate Transthioesterification Reactions. Academic Article uri icon

Overview

abstract

  • Ubiquitin (Ub) regulates a wide array of cellular processes through post-translational modification of protein substrates. Ub is conjugated at its C-terminus to target proteins via an enzymatic cascade in which covalently bound Ub thioesters are transferred from E1 activating enzymes to E2 conjugating enzymes, and then to certain E3 protein ligases. These transthioesterification reactions proceed via transient tetrahedral intermediates. A variety of chemical strategies have been used to capture E1-Ub-E2 and E2-Ub-E3 mimics, but these introduce modifications that disrupt atomic spacing at the linkage point relative to the native tetrahedral intermediate. We have developed a biselectrophilic PSAN warhead that can be installed in place of the conserved C-terminal glycine in Ub and used to form ternary protein complexes linked via cyanomethyldithioacetals that closely mimic the native tetrahedral intermediates. Investigation of the reactivity of the warhead and substituted analogues led to an effective semisynthetic route to Ub-1-PSAN, which was used to form a ternary E1-Ub*-E2 complex as a mimic of the transthioesterification intermediate.

publication date

  • May 23, 2024

Research

keywords

  • Ubiquitin

Identity

PubMed Central ID

  • PMC11165569

Scopus Document Identifier

  • 85194289926

Digital Object Identifier (DOI)

  • 10.1021/acs.orglett.4c01102

PubMed ID

  • 38781175

Additional Document Info

volume

  • 26

issue

  • 22