Article

A Selective Chemical Probe for Coenzyme A-Requiring Enzymes

Department of Chemistry, University of Illinois, Urbana-Champaign, Urbana, Illinois, United States
Angewandte Chemie International Edition (Impact Factor: 11.26). 10/2007; 46(40):7621-4. DOI: 10.1002/anie.200702485
Source: PubMed

ABSTRACT

Transferasen markiert: Eine auf dem Coenzym A (CoA) basierende Affinitätssonde mit einer Sulfoxycarbamat-Funktion erkennt eine Reihe von Acetyltransferasen selektiv gegenüber anderen Enzymen und Proteinen. Es verbleibt eine Desthiobiotin-Markierung, die für Western-Blots und die massenspektrometrische Charakterisierung genutzt werden kann (siehe Bild; Nu=Nucleophil).

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    • "Based on enzyme kinetics a ping-pong mechanism was proposed [23]. However, it was demonstrated that an electrophilic acetyl-CoA affinity labellingbased probe did not target a residue that is critical for catalysis, arguing against a ping-pong mechanism [24], but a ternary complex mechanism could not be confirmed either. Despite the fact that p300 contains a cysteine in the binding pocket no mutagenesis studies have yet been performed to investigate whether this cysteine is important for HAT activity. "
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    • "As all cysteines of HSP90 are located within its middle domain, small molecules that react with those cysteines may represent a new class of inhibitors distinct from those that target either the N-terminal ATP-binding pocket or the C-terminal domain of the chaperone. It was previously shown that cysteine residues of coenzyme A (CoA)-utilising enzymes can be selectively targeted by a mildly electrophilic sulphoxythiocarbamate-CoA analogue with the formation of stable thiocarbamate adducts (Hwang et al, 2007). "
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