# Deciphering the hydrolysis/transglycosylation partition in hydrolytic glycoside hydrolases

Régis Fauré

► To cite this version:

Régis Fauré. Deciphering the hydrolysis/transglycosylation partition in hydrolytic glycoside hydrolases. 30th International Carbohydrate Symposium, Jul 2022, Florianopolis, Brazil. hal-04791186

HAL Id: hal-04791186

https://hal.science/hal-04791186v1

Submitted on 11 Feb 2026

HAL is a multi-disciplinary open access
archive for the deposit and dissemination of sci-
entific research documents, whether they are pub-
lished or not. The documents may come from
teaching and research institutions in France or
abroad, or from public or private research centers.

L'archive ouverte pluridisciplinaire HAL, est
destinée au dépôt et à la diffusion de documents
scientifiques de niveau recherche, publiés ou non,
émanant des établissements d'enseignement et de
recherche français ou étrangers, des laboratoires
publics ou privés.

<figure><img src="image_1.png" /></figure>

Distributed under a Creative Commons CC BY 4.0 - Attribution - International License
<figure><img src="image_2.png" /></figure>

DECIPHERING THE HYDROLYSIS/TRANSGLYCOSYLATION PARTITION
IN HYDROLYTIC GLYCOSIDE HYDROLASES

Régis Fauré¹*

¹Toulouse Biotechnology Institute (TBI), Université de Toulouse, CNRS, INRAE, INSA, Toulouse, France,
*regis.faure@insa-toulouse.fr

Carbohydrate-active enzymes, such as glycoside hydrolases (GHs), are highly attractive tools for glycochemists, providing the means to synthesize glycosidic bonds. The vast biodiversity of GHs constitutes a reservoir of enzyme candidates and the potential to synthesize almost any glycosidic bond. However, most GHs primarily hydrolyze glycosidic bonds, with transglycosylation being a concomitant minority reaction. Fortunately, the native properties of GHs are amenable to engineering aimed at modifying the transglycosylation/hydrolysis (T/H) ratio.

A series of studies by our group has shed light on the T/H equilibrium in retaining GHs and led to the development of a molecular evolution strategy to switch the activity of these hydrolases towards synthetic activity [1]. Using protein engineering it has been possible to drastically diminish hydrolysis, while retaining or even enhancing glycosynthetic activity. In best cases, evolved transglycosylases (TGs) displaying transfer rates close to 100% have been obtained. Mostly, these enzymes procure stable products in high yields (> 70%) [2,3]. The careful study of engineered TGs has provided further insight into the determinants of the T/H partition and generic engineering rules can be used to create TGs starting with any retaining GH [4,5].

During my lecture, I will provide an overview of our achievements and relate our findings to kinetic studies performed on mutants that almost exclusively catalyze transglycosylation reactions. Moreover, I will present recent work that provides some structural and molecular dynamics insights into how engineered transglycosylases function. My overall take home message is that the engineering of GHs to create tailored TGs is now within of most researchers. Consequently, glycochemists can expand their toolbox and more easily access a wide variety of carbohydrate motifs.

Acknowledgement: This work was supported by INRAE (Institut National de la Recherche pour l'Agriculture, l'Alimentation et l'Environnement) and CSC (China Scholarship Council), and was performed in the framework of the French Danish research collaboration Program (IFD) and of ERA-NET BIOSURF.

Keywords: biocatalysis, glycoside hydrolase, molecular evolution, transglycosylation, molecular interactions

References:

[1] B. Bissaro et al., *Biochem. J.* 2015, 467(1), 17.

[2] B. Bissaro et al., *ACS Catal.* 2015, 5(8), 4598.

[3] J. Durand et al., *ACS Catal.* 2016, 6(12), 8264.

[4] J. Zhao et al., *New Biotechnol.* 2021, 62, 68.

[5] D. Teze et al., *Chem. Eur. J.* 2021, 27, 10323.