Ecole Doctorale COMPLEXITE DU VIVANT – Fiche Projet CONCOURS
Nom et prénom du directeur de thèse: MICHEL, Gurvan (DR2 CNRS, HDR)
Coordonnées Tel : 0033 (0)298292330
e-mail : gurvan.michel@sb-roscoff.fr
Nom et prénom du co-directeur de thèse: TELLIER, Charles (Pr Université de Nantes, HDR)
Coordonnées Tel : 0033 (0)251125733
e-mail : charles.tellier@univ-nantes.fr
Nom et prénom du co-encadrant (non HdR ) : DALIGAULT, Franck (MCU Université de Nantes)
Coordonnées Tel : 0033 (0)251125733
e-mail : franck.daligault@univ-nantes.fr
Nom et prénom du responsable de l’équipe : Czjzek Mirjam
Nombre de chercheurs et enseignants-chercheurs statutaires de l’équipe titulaires d’une HDR : 4
Nom et prénom du responsable du laboratoire : Boyen Catherine
Intitulé du laboratoire et N° d’unité : UMR8227, Laboratoire de Biologie Intégrative des Modèles Marins
Spécialité : Biologie de Macro-algues, microbiologie et biochimie
Titre du projet de thèse : Identification de spécificité de substrat et analyse biochimique et structurale de
sulfatases actives sur polysaccharides de macroalgues
Résumé du projet de thèse (1 page maximum, en anglais)
Brown, green and red macroalgae (commonly referred to as seaweeds) dominate the primary production in coastal
ecosystems and represent a huge biomass which is mainly constituted of polysaccharides. These diverse and complex
polymers essentially differ from land plant polysaccharides. Notably, seaweeds are characterized by their abundance in
sulfated polysaccharides: fucoidans in brown algae; ulvans in green algae; agars, porphyrans and carrageenans in red algae
[1]. Such sulfated polysaccharides are absent in land plants and are reminiscent of the sulfated glycosaminoglycans from the
extracellular matrix of animals. Despite the promising biological properties of these sulfated polysaccharides (e.g. immunestimulant, anti-viral, anti-coagulant, etc), algal biomass is underexploited and high value products based on algal
polysaccharides and oligosaccharides remain rare. The main bottleneck for the development of a seaweed-based
bioeconomy is the lack of enzymes which can specifically modify their structure, and thus allow the tailoring of their
biological properties. This is notably the case of sulfatases specific for algal polysaccharides which remain essentially
unknown.
To tackle this problem, the Marine Glycobiology group has developed the last years a marine bacterial model, Zobellia
galactanivorans, which is able to assimilate most of the algal polysaccharides as sole carbon sources. The genomic analysis
of this marine flavobacterium has confirmed its huge capacity for polysaccharide degradation with the presence of more
than 140 glycoside hydrolase (GH) and 71 sulfatase genes in its genome. These GH and sulfatase genes are usually group
together in Polysaccharide Utilization Loci (PUL) and for instance, we have demonstrated the existence of PULs dedicated
to the assimilation of agars and porphyrans [2]. This strongly supports that the sulfatases of these PULs are specific for the
modification of sulfated algal polysaccharides.
We have recently overexpressed soluble proteins about 50 sulfatases from Z. galactanivorans. The next step is now to
determine the exact function of these diverse sulfatases, and notably their precise substrate specificity. The candidate will be
part of a joint-research project between the SBR (Roscoff) and the Université de Nantes (UN), in the context of the GlycoOuest network (http://www.glyco-ouest.fr/) which has awarded this project with a PhD fellowship (region Bretagne –
region pays de la Loire). The candidate will be involved in the development of innovative screening methods to identify
sulfatase substrate specificities (UN). He will also characterize novel sulfatases specific for algal polysaccharides, both at
the biochemical and 3D structural level (SBR). Finally, some of these sulfatases will be used in a bioengineering approach
(UN-SBR), for instance to modify the regioselectivity or substrate specificity by directed evolution methods.
1. Popper ZA, Michel G, Hervé C, Domozych D, Willats WGT, Tuohy MG, Kloareg B, Stengel DB (2011) Evolution and
diversity of plant cell walls: from algae to flowering plants. Annual Review of Plant Biology, 62, 567-590.
2. Hehemann J-H, Correc G, Barbeyron T, Helbert W, Czjzek M and Michel G (2010) Transfer of carbohydrate-active
enzymes from marine bacteria to Japanese gut microbiota. Nature, 464, 908-912.
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Ecole Doctorale COMPLEXITE DU VIVANT – Fiche Projet CONCOURS
Thèses actuellement en cours dans l’équipe
Nom et Prénom du doctorant
Siméon Amandine
Matard Maria
Nom du directeur de thèse
Bernard Kloareg
Mirjam Czjzek
Année de 1ere
inscription et
Ecole Doctorale
2014
2014
Financement pendant la thèse
Région Bretagne-ressources propres
CIFRE
Trois publications récentes du directeur de thèse (du co-directeur ou du co-encadrant s’il y a lieu).Mettre en gras le nom
du directeur de thèse.
Directeur
Labourel A, Jam M, Legentil L, Sylla B, Hehemann JH, Ferrières V, Czjzek M, Michel G. (2015) Structural and
biochemical characterization of the laminarinase ZgLamCGH16 from Zobellia galactanivorans suggests preferred
recognition of branched laminarin. Acta Crystallographica D, 71, 173-84.
Labourel A, Jam M, Jeudy A, Hehemann JH, Czjzek M, Michel G. (2014) The β-glucanase ZgLamA from Zobellia
galactanivorans evolved a bent active site adapted for efficient degradation of algal laminarin. J Biol Chem, 289, 2027-42.
Thomas F, Barbeyron T, Tonon T, Genicot S, Czjzek M and Michel G (2012) Characterization of the first alginolytic
operons in a marine bacterium: From their emergence in marine Flavobacteriia to their independent transfers to marine
Proteobacteria and human gut Bacteroides. Environmental Microbiology, 14, 2379-94.
Co-directeur
Teze D, Daligault F, Ferrières V, Sanejouand YH, Tellier C (2015) Semi-rational approach for converting a GH36 αglycosidase into an α-transglycosidase. Glycobiology. 25, 420-7.
André-Miral C, Koné FM, Solleux C, Grandjean C, Dion M, Tran V, Tellier C (2015) De novo design of a trans-β-Nacetylglucosaminidase activity from a GH1 β-glycosidase by mechanism engineering. Glycobiology. 25, 394-402
Teze D, Hendrickx J, Czjzek M, Ropartz D, Sanejouand YH, Tran V, Tellier C, Dion M. (2014) Semi-rational approach
for converting a GH1 β-glycosidase into a β-transglycosidase. Protein Eng Des Sel. 27, 13-9.
Docteurs encadrés par le directeur de thèse ayant soutenu après septembre 2010 et publications relatives à leur sujet de thèse.
Mettre en gras le nom du directeur de thèse et celui du docteur.
Nom Prénom : Thomas François
Date de soutenance : 23 Sep 2011
Durée de thèse (en mois): 37
Ecole Doctorale : ED-387 Iviv
Publications :
Thomas F, Hehemann JH, Rebuffet E, Czjzek M, Michel G. (2011) Environmental and gut bacteroidetes: the food
connection. Front Microbiol 2:93.
Thomas F, Barbeyron T, Michel G. (2011) Evaluation of reference genes for real-time quantitative PCR in the marine
flavobacterium Zobellia galactanivorans. J Microbiol Methods, 84, 61-6.
Thomas F, Barbeyron T, Tonon T, Génicot S, Czjzek M, Michel G. (2012) Characterization of the first alginolytic
operons in a marine bacterium: from their emergence in marine Flavobacteriia to their independent transfers to marine
Proteobacteria and human gut Bacteroides. Environ Microbiol. 14, 2379-94.
Hehemann JH, Correc G, Thomas F, Bernard T, Barbeyron T, Jam M, Helbert W, Michel G, Czjzek M (2012)
Biochemical and structural characterization of the complex agarolytic enzyme system from the marine bacterium
Zobellia galactanivorans. J Biol Chem. 287(36):30571-84.
Thomas F, Lundqvist LC, Jam M, Jeudy A, Barbeyron T, Sandström C, Michel G, Czjzek M (2013) Comparative
characterization of two marine alginate lyases from Zobellia galactanivorans reveals distinct modes of action and
exquisite adaptation to their natural substrate. J Biol Chem. 288, 23021-37.
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Ecole Doctorale COMPLEXITE DU VIVANT – Fiche Projet CONCOURS
Nom Prénom : Labourel Aurore
Date de soutenance : 28 Oct 2013
Durée de thèse (en mois): 36
Ecole Doctorale : ED-387 Iviv
Publications :
Labourel A, Jam M, Jeudy A, Hehemann JH, Czjzek M, Michel G (2014) The β-glucanase ZgLamA from Zobellia
galactanivorans evolved a bent active site adapted for an efficient degradation of algal laminarin, J. Biol Chem, 289,
2027-42
Labourel A, Jam M, Legentil L, Sylla B, Hehemann JH, Ferrières V, Czjzek M, Michel G (2015) Structural and
biochemical characterization of the laminarinase ZgLamCGH16 from Zobellia galactanivorans suggests preferred
recognition of branched laminarin. Acta Crystallogr D 71, 173-84
Groisillier A, Labourel A, Michel G, Tonon T (2015) The Mannitol Utilization System of the Marine Bacterium
Zobellia galactanivorans. Appl Environ Microbiol. 81, 1799-812.
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