Institut de Biologie StructuraleGrenoble / France

News of the SAGAG Vivès team

June 2018

DOUBLE LABELLING TO FACILITATE THE STUDY OF GLYCOSAMINOGLYCANS

Heparan sulfate (HS) are sulfated polysaccharides of the Glycosaminoglycans family that participate in many cellular processes because of their ability to interact and modulate a wide range of signalling proteins. These interactions involve particular HS motifs, defined by their saccharide sequence and sulfation profile. However, the structural features of these functional domains remain mostly unknown, due to the molecular complexity of these polysaccharides and a lack of tools dedicated to their analysis.
In this context, the researchers of the SAGAGAG group, in collaboration with the Parisian Institute of Molecular Chemistry and the LG2A laboratory in Amiens, have developed a method allowing a double labelling of HS oligosaccharides, using Thia-Michael type addition and deuterium incorporation, respectively at the non-reducing and reducing ends of the sugar. This new labelling technique allows the combination of microgram-scale oligosaccharide labelling and mass spectrometric analysis, without altering HS/protein recognition properties, as demonstrated for heparinase I and HSulf-2 enzymes. This method is a new tool that should allow new developments for the sequencing of GAG oligosaccharides and the elucidation of new structure/function relationships.

A microscale double labelling of GAG oligosaccharides compatible with enzymatic treatment and mass spectrometry. Przybylski C, Bonnet V, Vivès RR. Chemical Communications ; 55(29):4182-4185.

https://doi.org/10.1039/C9CC00254E
SAGAG-Vivès team

Organization of an International INSERM Workshop on GAGs, Bordeaux 19-21 June 2019

April 2018

New insights into the recognition mechanisms of Heparan sulfate by SULF sulfatases

SAGAG-Vivès team

Through their ability to edit sulfation pattern of complex Heparan Sulfate (HS) polysaccharides, Sulf extracellular endosulfatases have emerged as critical regulators of many biological processes, including tumor progression. However, study of Sulfs remains extremely intricate and progress in characterizing their functional and structural features has been hampered by limited access to recombinant enzyme. In this study, IBS resaearchers and their collaborators unlock this critical bottleneck, by reporting an efficient expression and purification system of recombinant HSulf-2 in mammalian HEK293 cells. This novel source of enzyme enabled them to investigate the way the enzyme domain organization dictates its functional properties. By generating mutants, they confirmed previous studies that HSulf-2 catalytic (CAT) domain was sufficient to elicit arylsulfatase activity and that its hydrophilic (HD) domain was necessary to desulfate complex polysaccharides such as HS. In addition, they demonstrated for the first time that high affinity binding of HS substrates occurred through the coordinated action of both domains, and we identified and characterized 2 novel HS binding sites within the CAT domain. Altogether, their findings contribute to better understand the molecular mechanism governing HSulf-2 substrate recognition and processing. Furthermore, access to purified recombinant protein opens new perspectives for the resolution of HSulf structure and molecular features, as well as for the development of Sulf-specific inhibitors.

Expression and purification of recombinant extracellular sulfatase HSulf-2 allows deciphering of enzyme sub-domain coordinated role for the binding and 6-O-desulfation of heparan sulfate. Seffouh A, El Masri R, Makshakova O, Gout E, Hassoun ZEO, Andrieu JP, Lortat-Jacob H, Vivès RR. Cell. Mol. Life Sci. (2019).
https://doi.org/10.1007/s00018-019-03027-2

October 2018

Yoann Crétinon, SAGAG-Vivès team
Welcome to Yoann Crétinon, who is starting a PhD on the structural analysis of Sulf enzymes


September 2018

SAGAG Vivès : 3rd scientific meeting of the GDR GAG
The 3rd scientific meeting of the GDR GAG will take place next 24th and 25th of September, in Lille. The 25th is open to all.
Registration is free, but mandatory.

Registration until the 15th of September 2018.

More information....


May 2018

A PhD position devoted to the structural analysis of Sulf extracellular sulfatases is open for application in the SAGAG-Vivès team. This position is part of a collaboration between the academic group SAGAG at IBS and an industial partner. The position is co-funded by the private partner and IDEX Université Grenoble Alpes – CDP Glyco@Alps.

More information...

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