Role of the Two Catalytic Domains of DSR-E Dextransucrase and Their Involvement in the Formation of Highly α-1,2 Branched Dextran

Fabre, Émeline; Bozonnet, Sophie; Arcache, Audrey; Willemot, René‐Marc; Vignon, M.R.; Monsan, Pierre; Remaud‐Siméon, Magali

doi:10.1128/jb.187.1.296-303.2005

Cited by 71 publications

(84 citation statements)

References 26 publications

(23 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Evidence of the Dextran Binding Ability of ⌬N 123 -GBD-CD2-The ␣-(132) branching sucrase ⌬N 123 -GBD-CD2 is a truncated enzyme that was designed from DSR-E, a GH70 glucansucrase with two catalytic domains (CD1 and CD2) separated by a putative GBD rich in repeats proposed to be involved in the glucan binding ability of several enzymes from the GH70 family (27,57). The ⌬N 123 -GBD-CD2 enzyme catalyzes transglucosylation reaction from sucrose to dextran or isomalto-oligosaccharide acceptors, through the formation of ␣-(132) branches.…”

Section: Resultsmentioning

confidence: 99%

Structural Insights into the Carbohydrate Binding Ability of an α-(1→2) Branching Sucrase from Glycoside Hydrolase Family 70

Brison

Malbert

Czaplicki

et al. 2016

Journal of Biological Chemistry

Self Cite

View full text Add to dashboard Cite

The ␣-(132) branching sucrase ⌬N 123 -GBD-CD2 is a transglucosylase belonging to glycoside hydrolase family 70 (GH70) that catalyzes the transfer of D-glucosyl units from sucrose to dextrans or gluco-oligosaccharides via the formation of ␣-(132) glucosidic linkages. The first structures of ⌬N 123 -GBD-CD2 in complex with D-glucose, isomaltosyl, or isomaltotriosyl residues were solved. The glucose complex revealed three glucose-binding sites in the catalytic gorge and six additional binding sites at the surface of domains B, IV, and V. Soaking with isomaltotriose or gluco-oligosaccharides led to structures in which isomaltosyl or isomaltotriosyl residues were found in glucan binding pockets located in domain V. One aromatic residue is systematically identified at the bottom of these pockets in stacking interaction with one glucosyl moiety. The carbohydrate is also maintained by a network of hydrogen bonds and van der Waals interactions. The sequence of these binding pockets is conserved and repeatedly present in domain V of several GH70 glucansucrases known to bind ␣-glucans. These findings provide the first structural evidence of the molecular interaction occurring between isomalto-oligosaccharides and domain V of the GH70 enzymes.The glucosyltransferases of glycoside hydrolase family 70 (GH70), 4 namely the glucansucrases, the 4,6-␣-glucanotransferases, and the branching sucrases, are ␣-retaining transglucosylases produced by various lactic acid bacteria from Leuconostoc, Streptococcus, Weissella, and Lactobacillus genera (1-3). Glucansucrases from Leuconostoc spp. have been mainly studied for their industrial applications in the production of dextrans or prebiotic gluco-oligosaccharides (4 -7), whereas investigations on streptococcal glucansucrases were mostly motivated by their involvement in the accumulation of streptococci on tooth enamel and subsequent human dental caries formation (8). Glucansucrases catalyze the transfer of D-glucopyranosyl moieties from sucrose to acceptor molecules through the formation of a ␤-D-glucosyl-enzyme intermediate. They synthesize ␣-glucans, which vary in terms of size, osidic linkages as well as degree and arrangement of branching. Devoid of polymerase activity, the ␣-(132) branching sucrases are specialized in dextran branching through the formation of ␣-(132) glucosidic linkages from sucrose to dextran acceptor ( Fig. 1) (9, 10). In the absence of acceptor, these enzymes essentially catalyze sucrose hydrolysis.Glucansucrases are also known to bind dextrans via a carbohydrate-binding domain remote from the active site (2, 11). This domain is referred to as the glucan-binding domain (GBD) and is not classified in the CAZy database. Carbohydrate-protein interactions often play critical roles in the catalytic activities of carbohydrate active enzymes involved in polysaccharide synthesis, degradation, or decoration. Carbohydrate-binding sites may be intrinsic components of catalytic sites, but may also exert essential functions when located in non-catalytic modules (12). Eviden...

show abstract

Section: Resultsmentioning

confidence: 99%

Structural Insights into the Carbohydrate Binding Ability of an α-(1→2) Branching Sucrase from Glycoside Hydrolase Family 70

Brison

Malbert

Czaplicki

et al. 2016

Journal of Biological Chemistry

Self Cite

View full text Add to dashboard Cite

show abstract

“…Interestingly, BRS-B exhibits numerous sequence similarities with GBD-CD2 and BRS-A from L. citreum NRRL B-1299, two branching sucrases (19,21). In particular, Phe-675 of motif II and Ile-783, His-785, Lys-789, and Val-795 of motif IV are only conserved in the branching sucrases.…”

Section: Comparison Of Brs-b With Other Branching Sucrases and Glucanmentioning

confidence: 97%

“…According to our biochemical and phylogenetic analyses, branching sucrases could also constitute a new GH70 subgroup. Five enzymes of this group have now been characterized, including the engineered ␣-(132) branching sucrase GBD-CD2 (19,20), BRS-A (21), BRS-B, BRS-C, and BRS-D.…”

Section: Characterization Of Two New Putative Branching Sucrases and mentioning

confidence: 99%

See 1 more Smart Citation

Characterization of the First α-(1→3) Branching Sucrases of the GH70 Family

Vuillemin

Claverie

Brison

et al. 2016

Journal of Biological Chemistry

Self Cite

View full text Add to dashboard Cite

Leuconostoc citreum NRRL B-742 has been known for years to produce a highly ␣-(133)-branched dextran for which the synthesis had never been elucidated. In this work a gene coding for a putative ␣-transglucosylase of the GH70 family was identified in the reported genome of this bacteria and functionally characterized. From sucrose alone, the corresponding recombinant protein, named BRS-B, mainly catalyzed sucrose hydrolysis and leucrose synthesis. However, in the presence of sucrose and a dextran acceptor, the enzyme efficiently transferred the glucosyl residue from sucrose to linear ␣-(136) dextrans through the specific formation of ␣-(133) linkages. To date, BRS-B is the first reported ␣-(133) branching sucrase. Using a suitable sucrose/dextran ratio, a comb-like dextran with 50% of ␣-(133) branching was synthesized, suggesting that BRS-B is likely involved in the comb-like dextran produced by L. citreum NRRL B-742. In addition, data mining based on the search for specific sequence motifs allowed the identification of two genes putatively coding for branching sucrases in the genome of Leuconostoc fallax KCTC3537 and Lactobacillus kunkeei EFB6. Biochemical characterization of the corresponding recombinant enzymes confirmed their branching specificity, revealing that branching sucrases are not only found in L. citreum species. According to phylogenetic analyses, these enzymes are proposed to constitute a new subgroup of the GH70 family.Numerous lactic acid bacteria from the Leuconostoc genus isolated from different habitats, such as sugar juice, fermenting vegetables, or dairy products, have long been known to produce slimes in sucrose solution (1, 2). These slimy compounds were rapidly characterized as dextrans, homopolymers of ␣-D-glucopyranosyl units mainly linked by ␣-(136) linkages. Dextrans with a high content of ␣-(136) linkages and a low degree of branching found their first industrial applications in the 1940s as a source of synthetic blood volume expanders (3). These findings motivated Jeanes et al. (22) to investigate the diversity of polymers produced during sucrose fermentation by different strains of lactic acid bacteria. A total of 96 strains were screened, and their dextrans were structurally characterized. In this study one strain, Leuconostoc mesenteroides NRRL B-742, also known as L. mesenteroides ATCC 13146 and renamed Leuconostoc citreum NRRL B-742 (4), received particular attention. Indeed, this strain, first isolated from a can of spoiled tomatoes in 1927 (1), was shown to produce two types of dextrans that differed by their structures and degree of solubility from sucrose. The less soluble polymer contained 75% of ␣-(136) linkages and 15% of ␣-(134) linkages, whereas the more soluble polymer displayed an uncommon comb-like structure consisting of a linear backbone of ␣-(136)-D-glucopyranosyl residues grafted with one ␣-(133)-linked glucosyl unit on every glucosyl moiety (5-9). Concomitantly with those findings, dextrans were shown to be synthesized by ␣-transglucosylases, commonly named g...

show abstract

“…It is the largest glucansucrase (313 kDa) and has two catalytic domains, CD1 and CD2 of GH70 connected by a glucan-binding domain (GBD) (Bozonnet et al 2002). Dissection of DSR-E revealed CD1 and CD2 to be responsible for synthesis of α-1,6-and α-1,2-linkages, respectively (Fabre et al 2005). The truncated variant GBD-CD2 was found from the donor sucrose to be purely catalysing α-1,2-transglucosylation to dextran and α-1,6-glucooligosaccharide acceptors.…”

Section: Specificity Engineering In Clan Gh-hmentioning

confidence: 99%

An enzyme family reunion — similarities, differences and eccentricities in actions on α-glucans

et al. 2008

Self Cite

View full text Add to dashboard Cite

α-Glucans in general, including starch, glycogen and their derived oligosaccharides are processed by a host of more or less closely related enzymes that represent wide diversity in structure, mechanism, specificity and biological role. Sophisticated three-dimensional structures continue to emerge hand-in-hand with the gaining of novel insight in modes of action. We are witnessing the "test of time" blending with remaining questions and new relationships for these enzymes. Information from both within and outside of ALAMY 3 Symposium will provide examples on what the family contains and outline some future directions. In 2007 a quantum leap crowned the structural biology by the glucansucrase crystal structure. This initiates the disclosure of the mystery on the organisation of the multidomain structure and the "robotics mechanism" of this group of enzymes. The central issue on architecture and domain interplay in multidomain enzymes is also relevant in connection with the recent focus on carbohydrate-binding domains as well as on surface binding sites and their long underrated potential. Other questions include, how different or similar are glycoside hydrolase families 13 and 31 and is the lid finally lifted off the disguise of the starch lyase, also belonging to family 31? Is family 57 holding back secret specificities? Will the different families be sporting new "eccentric" functions, are there new families out there, and why are crystal structures of "simple" enzymes still missing? Indeed new understanding and discovery of biological roles continuously emphasize value of the collections of enzyme models, sequences, and evolutionary trees which will also be enabling advancement in design for useful and novel applications.

show abstract

Role of the Two Catalytic Domains of DSR-E Dextransucrase and Their Involvement in the Formation of Highly α-1,2 Branched Dextran

Cited by 71 publications

References 26 publications

Structural Insights into the Carbohydrate Binding Ability of an α-(1→2) Branching Sucrase from Glycoside Hydrolase Family 70

Structural Insights into the Carbohydrate Binding Ability of an α-(1→2) Branching Sucrase from Glycoside Hydrolase Family 70

Characterization of the First α-(1→3) Branching Sucrases of the GH70 Family

An enzyme family reunion — similarities, differences and eccentricities in actions on α-glucans

Contact Info

Product

Resources

About