The MG System, A Plant Enzymatic Process Used for Bioconjugation

S5.1 Glycomimetics
Location (hall): 
Start/end time: 
Tuesday, July 2, 2019 - 15:35 to 15:40

Jean Wilfried Fredy2, Giuliano Cutolo1, Marie Hubert-Roux2, Pierrick Gandolfo3, Hélène Castel3, Marie Schuler1, Arnaud Tatibouet1, Cyrille Sabot2, Pierre-Yves Renard2

1Institut de Chimie Organique et Analytique - ICOA UMR 7311 CNRS Université d’Orléans , Orléans, France, 2Normandie Univ, CNRS, UNIROUEN, INSA Rouen, COBRA (UMR 6014, Rouen, France, 3Normandie Univ, UNIROUEN, INSERM U1239, DC2N, Rouen, France

The diversity of enzymatic reactions involved in plant biological processes are largely underexplored to generate highly reactive chemical species under mild, aqueous conditions compatible with proteins. The release of isothiocyanate derivatives from glucosinolate precursors is a well-established defense mechanism against any aggression, which takes place specifically in plant families of the Brassicales order. [1-3] This biochemical process is promoted by myrosinases, a class of enzymes only present in plants, and which specifically hydrolyzes the anomeric carbon-sulfur bond of glucosinolates to generate isothiocyanates through a Lossen-type rearrangement.

In our poster, we describe whether this unique mode of action which occurs in complex biological environments, could be diverted to the in situ preparation of tailor-made isothiocyanate conjugates from chemically inert and water soluble precursors. It is noteworthy that rare examples of enzymatically-driven formation of bioconjugable chemical functions have been reported, most of them using horseradish peroxidase (HRP). Based on structural analysis of natural glucosinolates composed of about 130 members, and artificial glucosinolate-like structures, it seems that modifications on the side chain R should not significantly affect the recognition process, and more importantly the hydrolytic ability of myrosinase. [4-6] Accordingly, the introduction of (bio)conjugable handles or probes on the aglycon moiety should not interfere with the chemoenzymatic release of isothiocyanate, which could be used as a bioconjugation tool. [7]

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  4. D. Cerniauskaite, J. Rousseau, A. Sackus, P. Rollin and A. Tatibouët, Eur. J. Org. Chem. 2011, 2011, 2293-2300.
  5. R. Nehmé, H. Nehmé, G. Roux, D. Cerniauskaite, P. Morin, P. Rollin and A. Tatibouët, Anal. Chim. Acta 2014, 807, 153-158.
  6. G. Cutolo, F. Reise, M. Schuler, R. Nehmé, G. Despras, J. Brekalo, P. Morin, P.-Y. Renard, T. K. Lindhorst and A. Tatibouët, Org. Biomol. Chem., 2018, 16, 4900 – 4913.
  7. J. W. Fredy, G. Cutolo, B. Poret, R. Nehmé, M. Hubert-Roux, P. Gandolfo, H. Castel, M. Schuler, A. Tatibouët, C. Sabot, P.-Y. Renard, Bioconjugate Chemistry Article ASAP DOI: 10.1021/acs.bioconjchem.9b00153