CAZypedia - User contributions [en-ca]

User:Magali Remaud-Simeon

2012-08-23T09:09:53Z

Magali Remaud-Simeon:

User:Magali Remaud-Simeon

2012-08-23T09:07:52Z

Magali Remaud-Simeon:

User:Magali Remaud-Simeon

2012-08-23T08:59:40Z

Magali Remaud-Simeon:

800x600 Normal 0 21 false false false FR X-NONE X-NONE MicrosoftInternetExplorer4

Magali Remaud-Simeon graduated from the National Institute of Applied Science of Toulouse in 1985 and received her PhD in 1988. Then she was as Post-Doctotal Fellow at the University of Pensylvania where she worked with Prof D. Graves in the department of Chemical and Biomolecular Engineering. From 1990 to 2000, she was an associate professor at the Institute of Technology of the University of Toulouse in the department of Applied Biology. She joined the group of Biocatalysis of Prof. P. MONSAN at the "laboratoire d'Ingénierie des systèmes et des procédés" in 1994. Since 2001, she is a professor at the National Institute of Applied Science of Toulouse. As the head of the Enzyme Molecular Engineering and Catalysis group since 2001, she focuses her research activities on enzyme engineering for white biotechnology, green chemistry, Food/Feed industries and synthetic biology. Her areas of interest cover enzyme structure/activity relationship studies, kinetic resolution, evolution combining both rational and combinatorial approaches, and applications to the synthesis of new polysaccharides, oligosaccharides, glycoonjugates, esters and enantiopure compounds. She has been working on glucansucrases from GH family 70 and 13 since 1985. With her collaborators, she has investigated the mechanism of dextran, alternan and amylose biosynthesis by dextransucrase, alternansucrase and amylosucrase, respectively. Her work is currently focused on the search and generation of enzymes displaying new specificities and improved properties towards unnatural substrates.

E-mail: magali.remaud@insa-toulouse.fr http://www.lisbp.insa-toulouse.fr

<biblio>
#andre2010 pmid=21626747
#fabre2005 pmid=15601714
#moulis2006 pmid=16864576
#brison2012 pmid=22262856
#guerin2012 Guérin F, Barbe S., Pizzut-Serin S, Potocki-Véronèse G, Guieysse D, Guillet V, Monsan P, Mourey L, Remaud-Simeon M, André I and Tranier S.''Structural investigation of the thermostability and product specificity of amylosucrase from the bacterium Deinococcus geothermalis''. J. Biol Chem 2012; 287(9):6642-6654
#champion2009 Champion E, André I, Moulis C, Boutet J, Descroix K, Morel S, Monsan P, Mulard LA, Remaud-Simeon M. 2009a. ''Design of alpha-transglucosidases of controlled specificity for programmed chemoenzymatic synthesis of antigenic oligosaccharides''. J Am Chem Soc 2009; 131(21):7379-89
#albenne2004 Albenne C, Skov LK, Mirza O, Gajhede M, Feller G, D’Amico S, Andre G, Potocki-Véronèse G, Van Der Veen B, Monsan P, Remaud-Simeon M. ''Molecular basis of the amylose-like polymer formation catalysed by Neisseria polysaccharea amylosucrase''. J Biol Chem 2004; 279, 726-734
</biblio>

Normal 0 21 false false false FR X-NONE X-NONE

Normal 0 21 false false false FR X-NONE X-NONE

Normal 0 21 false false false FR X-NONE X-NONE

Glycoside Hydrolase Family 70

2012-08-23T08:38:24Z

Magali Remaud-Simeon:

{{UnderConstruction}}
* [[Author]]:
* [[Responsible Curator]]: ^^^Magali Remaud-Simeon^^^
----


<div style="float:right">
{| {{Prettytable}}
|-
|{{Hl2}} colspan="2" align="center" |'''Glycoside Hydrolase Family GH70'''
|-
|'''Clan'''
|GH-H
|-
|'''Mechanism'''
|retaining
|-
|'''Active site residues'''
|known
|-
|{{Hl2}} colspan="2" align="center" |'''CAZy DB link'''
|-
| colspan="2" |{{CAZyDBlink}}GH70.html
|}
</div>


== Substrate specificities ==
Normal 0 21 false false false FR X-NONE X-NONE
Normal 0 21 false false false FR X-NONE X-NONE

GH 70 family enzymes are transglucosylases produced by lactic acid bacteria from Streptococcus, Leuconostoc, Weisella or Lactobacillus genera. Together with the GH 13 and GH77 enzymes, they form the clan GH-H.

Most of the enzymes classified in this family use sucrose as the D-glucopyranosyl donor to synthesize a-D-glucans of high molecular mass (>106 Da) with the concomitant release of D-fructose. They are also referred to as glucosyltransferases (GTF) or glucansucrases (GS) <cite>Sidebotham1974 Monchois1999 Leemhuis2012 Andre2010</cite>. The first glucansucrase was isolated from sucrose-broth cultures of a strain of Ln. mesenteroides <Cite>Hehre1941 Hehre1942</Cite>. The enzyme was shown to synthesize water-soluble dextran (a-1,6 linked D-glucan) from sucrose alone. Dextran from Ln. mesenteroides sp. was the first microbial polysaccharide to be commercialized and used for pharmaceutical and fine chemical applications. The glucansucrases produced by Streptococcus sp. were extensively studied on account of their major role in the formation of dental caries <Cite>Sidebotham1974 Monchois 1999</Cite>.

Depending on their specificity, glucansucrases catalyze the formation of linear as well as branched a-D-glucan chains with various types of glycosidic linkages, namely a-1,2; a-1,3; a-1,4; and/or a-1,6 <cite>Sidebotham1974 Andre2010 Jeanes1954</Cite>. They are classified by the nomenclature Committee of the International Union of Biochemistry and Molecular Biology on the basis of the reaction catalyzed and the specificity ; dextransucrase (sucrose:1,6-a-D-glucosyltransferase; EC 2.4.1.5), alternansucrase (sucrose:1,6(1,3)-a-D-glucan-6(3)-a-D-glucosyltransferase, EC2.4.1.140), mutansucrase (sucrose:1,3-a-D-glucan-3-a-D-glucosyltransferase; EC 2.4.1.5) and reuteransucrase (sucrose:1,4(6-a-D-glucan-4(6)-a-D-glucosyltransferase; EC 2.4.1.5). A wide range of a-D-glucans, varying in size, structure, degree of branching and spatial arrangements can thus be produced by GH70 family members <cite>Sidebotham1974 Monchois1999 Leemhuis2012 Andre2010</cite>.

Sucrose analogues such as a-D-glucopyranosyl fluoride, p-nitrophenyl a-D-glucopyranoside, a-D-glucopyranosyl a-L-sorofuranoside and lactulosucrose were also reported as D-glucopyranosyl donors <cite>Genghof1972 Figures1976 Binder1983</cite>. GH70 glucansucrases also transfer the D-glucosyl units from sucrose onto hydroxyl acceptor groups. A large variety of acceptors may be recognized by glucansucrases including carbohydrates, alcohols, polyols or flavonoids to yield oligosaccharides or gluco-conjugates <cite>Monchois1999 Leemhuis2012 Andre2010 Koepsell1953 Nakahara1995 Richard2003 Bertrand2006</cite>. The structure of the resultant glucosylated product is dependent upon the enzyme specificity.

Glucansucrases also catalyze glucosyl exchange between their glucan products in a reaction known as disproportionation <cite>Binderb1983</cite>. Of note, some members of GH70 family produced by Lb. reuteri sp. were also reported to be able to use maltooligosaccharides as the glucosyl donor and to catalyze its transfer to maltooligosaccharide acceptors via the formation of a-1,6 linkages, thus acting as 4,6-a-glucanotransferases and revealing additional evolutionary relations between GH 70 and 13 families <cite>Kralj2011 Dobruchowska2012 </cite>.

One glucansucrase was shown to possess two catalytically active domains acting in tandem <cite>Fabre2005</Cite>. This enzyme was shown to be secreted by Ln. mesenteroides NRRLB-1299 (reclassified as Ln. citreum). These domains work cooperatively to synthesize dextran with more than 20 % a-1,2 branched linkages and are both classified in the GH70 family. One domain is responsible for the synthesis of the a-1,6 linked dextran chain whereas the second one is specific for the catalysis of a-1,2 branch formation. The truncated form of this enzyme carrying only the second catalytic domain was named a-1,2 branching sucrase as it does not catalyse sucrose polymerization and shows transglucosylase activity only in the presence of sucrose and linear a-1,6 dextran <cite>Brison2012 </Cite>.

== Kinetics and Mechanism ==
Normal 0 21 false false false FR X-NONE X-NONE Enzymes from GH family 70 belong to the same GH H as clan GH family 13 and 77 enzymes. They employ an a-retaining mechanism. The transfer of the glucosyl unit proceeds through the formation of a b-glucosyl ester of an aspartate side chain, which was first isolated by sequencing peptides provided by rapid quenching of enzymic reactions with labeled sucrose and extracellular glucosyltransferases from S. sobrinus <cite>Mooser1989 Mooser1991</Cite>. Once the glucosyl-enzyme intermediate is formed, the glucosyl units originating from sucrose may be transferred onto either water (hydrolysis reaction), D-fructose released from sucrose cleavage (sucrose isomer formation) or onto the growing glucan chain (main reaction) <cite>Mooser1989 Mooser1991 Moulis2006 Vujicic-Zagar2010</Cite>. When acceptors are introduced into the reaction mixture, acceptor glucosylation occurs at the expense of polymer formation, the competition between the two reactions being controlled by acceptor recognition <cite>Koepsell1953</Cite>. Polymer extension proceeds from the non-reducing end <cite>Moulis2006</Cite> and involves a single active site as observed in the tertiary structures of GH70 enzymes <cite>Vujicic-Zagar2010 Ito2011</Cite>. Normal 0 21 false false false FR X-NONE X-NONE

The catalytic domain of family 70 enzymes is often flanked at the N- and/or C-termini by sequences containing a series of homologous repeating units that confer glucan binding ability <cite>Monchois1999 Leemhuis2012 Janecek2000</cite>. They are found in domain V (see structure scheme below) and have also been shown to influence polymer size, enzyme activity, specificity and processivity <cite>Monchois1999 Leemhuis2012 Moulis2006</cite>. However, their precise role at the molecular level is still not fully understood <cite>Vujicic-Zagar2010 Ito2011</Cite>.
== Catalytic Residues ==
Normal 0 21 false false false FR X-NONE X-NONE

Sequence analysis, secondary structure prediction and tertiary structure comparison with enzymes from GH Family 13 enabled the localization of a putative catalytic triad that is strictly conserved in family 70 and similar to that found in GH family 13 <cite>Vujicic-Zagar2010 Ito2011</Cite>. This triad is formed by an aspartate (nucleophile) corresponding to the residue identified by peptide sequencing <cite>Mooser1989 Mooser1991</Cite>, a glutamate (acid/base catalyst) and a second aspartic acid that is critical for transition state stabilization <cite>Vujicic-Zagar2010 Ito2011</Cite>. The putative role of these residues in catalysis was further supported by mutations and structural analyses <cite>Monchois1999 Leemhuis2012 Andre2010</cite>.

== Three-dimensional structures ==
Normal 0 21 false false false FR X-NONE X-NONE

The 3D structures of GTF180-DN dextransucrase from Lb reuteri 180 <cite>Vujicic-Zagar2010</Cite>, GTF-SI from S. mutans <cite>Ito2011</Cite> and a-1,2 branching sucrase (engineered from DSR-E dextransucrase from Ln. citreum NRRL B-1299) <cite>Brison2012</Cite>, all revealed a unique fold organized as five distinct domains, named C, A, B, IV and V, and made up of peptide segments that are not consecutively arranged along the peptide chain. The catalytic domain of GH70 glucansucrases consists of a (b/a)8 barrel resembling that of family 13 enzymes but formed by sequences that have undergone circular permutation compared with the GH13 family domains <cite>Vujicic-Zagar2010 MacGregor1996</Cite>. The 3D structures of complexes with sucrose, maltose and acarbose enabled the mapping of the active site and the identification of some determinants of GH70 enzyme product specificity.

Normal 0 21 false false false FR X-NONE X-NONE

Available structures:

GTF180-DN (dextransucrase from Lb reuteri 180) : 3KLK, 3KLL, 3HZ3 <cite>Vujicic-Zagar2010</Cite>

GTF-SI (mutansucrase from S. mutans : 3AIE, 3AIC, 3AIB <cite>Ito2011</Cite>

GBD-CD2 (a-1,2 branching sucrase) : 3TTO <cite>Ito2011</Cite>
== Family Firsts ==
Normal 0 21 false false false FR X-NONE X-NONE

First stereochemistry determination : The stereochemistry was directly linked to the discovery of the enzyme from Ln. mesenteroides catalyzing dextran synthesis from sucrose by Hehre <cite>Hehre1941</Cite>

First amino acid sequences: Those of GTF-B from S. mutans and GTF-I from S. sobrinus Mfe28 simultaneously reported in two companion articles <cite>Shiroza1987 Ferretti1987</cite>

First catalytic nucleophile identification : identified first in Streptococcus sobrinus glucansucrase <cite>Mooser1989 Mooser1991</Cite>

First general acid/base residue identification:

On the basis of sequence alignments and secondary structure <cite>MacGregor1996 </cite>.

On the basis of 3D-structure <cite>Vujicic-Zagar2010 Pijning2008 </Cite>

First 3-D structure

The first 3-D structure for GH70 members was that of the GTF180-DN dextransucrase from Lb reuteri <cite>Vujicic-Zagar2010 Pijning2008 </Cite>

== References ==
Normal 0 21 false false false FR X-NONE X-NONE

<biblio>
#Sidebotham1974 pmid=4157174

#Monchois1999 pmid=10234842

#Leemhuis2012 pmid=22796091

#Andre2010 pmid=21626747

#Hehre1941 pmid=17775949

#Hehre1942 pmid=19871188

#Jeanes1954 Jeanes A, Haynes WC, Wilham CA, Rankin JC, Melvin EH, Austin MJ, Cluskey JE,Fisher BE, Tsuchiya HM, Rist CE Characterization and classification of dextrans from 96 strains of bacteria. J Am Chem Soc 1954; 76(20) 5041-5052. Doi: 10.1021/ja01649a011

#Genghof1972 pmid=5057594

#Figures1976 pmid=947539

#Binder1983 pmid=6671201

#Koepsell1953 pmid=13034840

#Nakahara1995 pmid=16535083

#Richard2003 pmid=12681910

#Bertrand2006 pmid=16530175

#Binderb1983 pmid=6671200

#Kralj2011 pmid=21948833

#Dobruchowska2012 pmid=22138321

#Fabre2005 pmid=15601714

#Brison2012 pmid=22262856

#Mooser1989 pmid=2523727

#Mooser1991 pmid=1827439

#Moulis2006 pmid=16864576

#Vujicic-Zagar2010 pmid=16880540

#Ito2011 pmid=21354427

#Janecek2000 pmid=11040428

#MacGregor1996 pmid = 8557114

#Shiroza1987 pmid=3040685

#Ferretti1987 pmid=3040686

#Pijning2008 Pijning T, Vujicic-Zagar A, Kralj S, Eeuwema W, Dijkhuizen L, Dijkstra, BW Biochemical and crystallographic characterization of a glucansucrase from Lactobacillus reuteri 180. Biocat Biotrans 2008; 26 (1-2) 12-17 DOI: 10.1080/10242420701789163

</biblio>
[[Category:Glycoside Hydrolase Families|GH070]]

Glycoside Hydrolase Family 70

2012-08-23T08:32:50Z

Magali Remaud-Simeon:

Glycoside Hydrolase Family 70

2012-08-21T15:45:39Z

Magali Remaud-Simeon:

{{UnderConstruction}}
* [[Author]]:
* [[Responsible Curator]]: ^^^Magali Remaud-Simeon^^^
----


<div style="float:right">
{| {{Prettytable}}
|-
|{{Hl2}} colspan="2" align="center" |'''Glycoside Hydrolase Family GH70'''
|-
|'''Clan'''
|GH-H
|-
|'''Mechanism'''
|retaining
|-
|'''Active site residues'''
|known
|-
|{{Hl2}} colspan="2" align="center" |'''CAZy DB link'''
|-
| colspan="2" |{{CAZyDBlink}}GH70.html
|}
</div>


== Substrate specificities ==
Normal 0 21 false false false FR X-NONE X-NONE
Normal 0 21 false false false FR X-NONE X-NONE

GH 70 family enzymes are transglucosylases produced by lactic acid bacteria from Streptococcus, Leuconostoc, Weisella or Lactobacillus genera. Together with the GH 13 and GH77 enzymes, they form the clan GH-H.

Most of the enzymes classified in this family use sucrose as the D-glucopyranosyl donor to synthesize a-D-glucans of high molecular mass (>106 Da) with the concomitant release of D-fructose. They are also referred to as glucosyltransferases (GTF) or glucansucrases (GS) <cite>Sidebotham1974 Monchois1999 Leemhuis2012 Andre2010</cite>. The first glucansucrase was isolated from sucrose-broth cultures of a strain of Ln. mesenteroides <Cite>Hehre1941 Hehre1942</Cite>. The enzyme was shown to synthesize water-soluble dextran (a-1,6 linked D-glucan) from sucrose alone. Dextran from Ln. mesenteroides sp. was the first microbial polysaccharide to be commercialized and used for pharmaceutical and fine chemical applications. The glucansucrases produced by Streptococcus sp. were extensively studied on account of their major role in the formation of dental caries <Cite>Sidebotham1974 Monchois 1999</Cite>.

Depending on their specificity, glucansucrases catalyze the formation of linear as well as branched a-D-glucan chains with various types of glycosidic linkages, namely a-1,2; a-1,3; a-1,4; and/or a-1,6 <cite>Sidebotham1974 Andre2010 Jeanes1954</Cite>. They are classified by the nomenclature Committee of the International Union of Biochemistry and Molecular Biology on the basis of the reaction catalyzed and the specificity ; dextransucrase (sucrose:1,6-a-D-glucosyltransferase; EC 2.4.1.5), alternansucrase (sucrose:1,6(1,3)-a-D-glucan-6(3)-a-D-glucosyltransferase, EC2.4.1.140), mutansucrase (sucrose:1,3-a-D-glucan-3-a-D-glucosyltransferase; EC 2.4.1.5) and reuteransucrase (sucrose:1,4(6-a-D-glucan-4(6)-a-D-glucosyltransferase; EC 2.4.1.5). A wide range of a-D-glucans, varying in size, structure, degree of branching and spatial arrangements can thus be produced by GH70 family members <cite>Sidebotham1974 Monchois1999 Leemhuis2012 Andre2010</cite>.

Sucrose analogues such as a-D-glucopyranosyl fluoride, p-nitrophenyl a-D-glucopyranoside, a-D-glucopyranosyl a-L-sorofuranoside and lactulosucrose were also reported as D-glucopyranosyl donors <cite>Genghof1972 Figures1976 Binder1983</cite>. GH70 glucansucrases also transfer the D-glucosyl units from sucrose onto hydroxyl acceptor groups. A large variety of acceptors may be recognized by glucansucrases including carbohydrates, alcohols, polyols or flavonoids to yield oligosaccharides or gluco-conjugates <cite>Monchois1999 Leemhuis2012 Andre2010 Koepsell1953 Nakahara1995 Richard2003 Bertrand2006</cite>. The structure of the resultant glucosylated product is dependent upon the enzyme specificity.

Glucansucrases also catalyze glucosyl exchange between their glucan products in a reaction known as disproportionation <cite>Binderb1983</cite>. Of note, some members of GH70 family produced by Lb. reuteri sp. were also reported to be able to use maltooligosaccharides as the glucosyl donor and to catalyze its transfer to maltooligosaccharide acceptors via the formation of a-1,6 linkages, thus acting as 4,6-a-glucanotransferases and revealing additional evolutionary relations between GH 70 and 13 families <cite>Kralj2011 Dobruchowska2012 </cite>.

One glucansucrase was shown to possess two catalytically active domains acting in tandem <cite>Fabre2005</Cite>. This enzyme was shown to be secreted by Ln. mesenteroides NRRLB-1299 (reclassified as Ln. citreum). These domains work cooperatively to synthesize dextran with more than 20 % a-1,2 branched linkages and are both classified in the GH70 family. One domain is responsible for the synthesis of the a-1,6 linked dextran chain whereas the second one is specific for the catalysis of a-1,2 branch formation. The truncated form of this enzyme carrying only the second catalytic domain was named a-1,2 branching sucrase as it does not catalyse sucrose polymerization and shows transglucosylase activity only in the presence of sucrose and linear a-1,6 dextran <cite>Brison2012 </Cite>.

== Kinetics and Mechanism ==
Normal 0 21 false false false FR X-NONE X-NONE Enzymes from GH family 70 belong to the same GH H as clan GH family 13 and 77 enzymes. They employ an a-retaining mechanism. The transfer of the glucosyl unit proceeds through the formation of a b-glucosyl ester of an aspartate side chain, which was first isolated by sequencing peptides provided by rapid quenching of enzymic reactions with labeled sucrose and extracellular glucosyltransferases from S. sobrinus <cite>Mooser1989 Mooser1991</Cite>. Once the glucosyl-enzyme intermediate is formed, the glucosyl units originating from sucrose may be transferred onto either water (hydrolysis reaction), D-fructose released from sucrose cleavage (sucrose isomer formation) or onto the growing glucan chain (main reaction) <cite>Mooser1989 Mooser1991 Moulis2006 Vujicic-Zagar2010</Cite>. When acceptors are introduced into the reaction mixture, acceptor glucosylation occurs at the expense of polymer formation, the competition between the two reactions being controlled by acceptor recognition <cite>Koepsell1953</Cite>. Polymer extension proceeds from the non-reducing end <cite>Moulis2006</Cite> and involves a single active site as observed in the tertiary structures of GH70 enzymes <cite>Vujicic-Zagar2010 Ito2011</Cite>. Normal 0 21 false false false FR X-NONE X-NONE

The catalytic domain of family 70 enzymes is often flanked at the N- and/or C-termini by sequences containing a series of homologous repeating units that confer glucan binding ability <cite>Monchois1999 Leemhuis2012 Janecek2000</cite>. They are found in domain V (see structure scheme below) and have also been shown to influence polymer size, enzyme activity, specificity and processivity <cite>Monchois1999 Leemhuis2012 Moulis2006</cite>. However, their precise role at the molecular level is still not fully understood <cite>Vujicic-Zagar2010 Ito2011</Cite>.
== Catalytic Residues ==
Normal 0 21 false false false FR X-NONE X-NONE

Sequence analysis, secondary structure prediction and tertiary structure comparison with enzymes from GH Family 13 enabled the localization of a putative catalytic triad that is strictly conserved in family 70 and similar to that found in GH family 13 <cite>Vujicic-Zagar2010 Ito2011</Cite>. This triad is formed by an aspartate (nucleophile) corresponding to the residue identified by peptide sequencing <cite>Mooser1989 Mooser1991</Cite>, a glutamate (acid/base catalyst) and a second aspartic acid that is critical for transition state stabilization <cite>Vujicic-Zagar2010 Ito2011</Cite>. The putative role of these residues in catalysis was further supported by mutations and structural analyses <cite>Monchois1999 Leemhuis2012 Andre2010</cite>.

== Three-dimensional structures ==
Normal 0 21 false false false FR X-NONE X-NONE

The 3D structures of GTF180-DN dextransucrase from Lb reuteri 180 <cite>Vujicic-Zagar2010</Cite>, GTF-SI from S. mutans <cite>Ito2011</Cite> and a-1,2 branching sucrase (engineered from DSR-E dextransucrase from Ln. citreum NRRL B-1299) <cite>Brison2012</Cite>, all revealed a unique fold organized as five distinct domains, named C, A, B, IV and V, and made up of peptide segments that are not consecutively arranged along the peptide chain. The catalytic domain of GH70 glucansucrases consists of a (b/a)8 barrel resembling that of family 13 enzymes but formed by sequences that have undergone circular permutation compared with the GH13 family domains <cite>Vujicic-Zagar2010 MacGregor1996</Cite>. The 3D structures of complexes with sucrose, maltose and acarbose enabled the mapping of the active site and the identification of some determinants of GH70 enzyme product specificity.

Normal 0 21 false false false FR X-NONE X-NONE

Available structures:

GTF180-DN (dextransucrase from Lb reuteri 180) : 3KLK, 3KLL, 3HZ3 <cite>Vujicic-Zagar2010</Cite>

GTF-SI (mutansucrase from S. mutans : 3AIE, 3AIC, 3AIB <cite>Ito2011</Cite>

GBD-CD2 (a-1,2 branching sucrase) : 3TTO <cite>Ito2011</Cite>
== Family Firsts ==
Normal 0 21 false false false FR X-NONE X-NONE

First stereochemistry determination : The stereochemistry was directly linked to the discovery of the enzyme from Ln. mesenteroides catalyzing dextran synthesis from sucrose by Hehre <cite>Hehre1941</Cite>

First amino acid sequences: Those of GTF-B from S. mutans and GTF-I from S. sobrinus Mfe28 simultaneously reported in two companion articles <cite>Shiroza1987 Ferretti1987</cite>

First catalytic nucleophile identification : identified first in Streptococcus sobrinus glucansucrase <cite>Mooser1989 Mooser1991</Cite>

First general acid/base residue identification:

On the basis of sequence alignments and secondary structure <cite>MacGregor1996 </cite>.

On the basis of 3D-structure <cite>Vujicic-Zagar2010 Pijning2008 </Cite>

First 3-D structure

The first 3-D structure for GH70 members was that of the GTF180-DN dextransucrase from Lb reuteri <cite>Vujicic-Zagar2010 Pijning2008 </Cite>

== References ==
Normal 0 21 false false false FR X-NONE X-NONE

<biblio>

#Sidebotham1974 pmid=4157174

#Monchois1999 pmid= 10234842

#Leemhuis2012 pmid= 22796091

#Andre2010 pmid= 21626747

#Hehre1941 pmid=17775949

#Hehre1942 pmid=19871188

#Jeanes1954 Jeanes A, Haynes WC, Wilham CA, Rankin JC, Melvin EH, Austin MJ, Cluskey JE,Fisher BE, Tsuchiya HM, Rist CE Characterization and classification of dextrans from 96 strains of bacteria. J Am Chem Soc 1954; 76(20) 5041-5052. Doi: 10.1021/ja01649a011

#Genghof1972 pmid=5057594

#Figures1976 pmid=947539

#Binder1983 pmid=6671201

#Koepsell1953 pmid=13034840

#Nakahara1995 pmid=16535083

#Richard2003 pmid=12681910

#Bertrand2006 pmid=16530175

#Binderb1983 pmid=6671200

#Kralj2011 pmid=21948833

#Dobruchowska2012 pmid=22138321

#Fabre2005 pmid=15601714

#Brison2012 pmid=22262856

#Mooser1989 pmid=2523727

#Mooser1991 pmid=1827439

#Moulis2006 pmid=16864576

#Vujicic-Zagar2010 pmid=16880540

#Ito2011 pmid=21354427

#Janecek2000 pmid=11040428

#MacGregor1996 pmid = 8557114

#Shiroza1987 pmid=3040685

#Ferretti1987 pmid= 3040686

#Pijning2008 Pijning T, Vujicic-Zagar A, Kralj S, Eeuwema W, Dijkhuizen L, Dijkstra, BW Biochemical and crystallographic characterization of a glucansucrase from Lactobacillus reuteri 180. Biocat Biotrans 2008; 26 (1-2) 12-17 DOI: 10.1080/10242420701789163

</biblio>
[[Category:Glycoside Hydrolase Families|GH070]]

Glycoside Hydrolase Family 70

2012-08-21T15:42:37Z

Magali Remaud-Simeon:

{{UnderConstruction}}
* [[Author]]:
* [[Responsible Curator]]: ^^^Magali Remaud-Simeon^^^
----


<div style="float:right">
{| {{Prettytable}}
|-
|{{Hl2}} colspan="2" align="center" |'''Glycoside Hydrolase Family GH70'''
|-
|'''Clan'''
|GH-H
|-
|'''Mechanism'''
|retaining
|-
|'''Active site residues'''
|known
|-
|{{Hl2}} colspan="2" align="center" |'''CAZy DB link'''
|-
| colspan="2" |{{CAZyDBlink}}GH70.html
|}
</div>


== Substrate specificities ==
Normal 0 21 false false false FR X-NONE X-NONE
Normal 0 21 false false false FR X-NONE X-NONE

GH 70 family enzymes are transglucosylases produced by lactic acid bacteria from Streptococcus, Leuconostoc, Weisella or Lactobacillus genera. Together with the GH 13 and GH77 enzymes, they form the clan GH-H.

Most of the enzymes classified in this family use sucrose as the D-glucopyranosyl donor to synthesize a-D-glucans of high molecular mass (>106 Da) with the concomitant release of D-fructose. They are also referred to as glucosyltransferases (GTF) or glucansucrases (GS) <cite>Sidebotham1974 Monchois1999 Leemhuis2012 Andre2010</cite>. The first glucansucrase was isolated from sucrose-broth cultures of a strain of Ln. mesenteroides <Cite>Hehre1941 Hehre1042</Cite>. The enzyme was shown to synthesize water-soluble dextran (a-1,6 linked D-glucan) from sucrose alone. Dextran from Ln. mesenteroides sp. was the first microbial polysaccharide to be commercialized and used for pharmaceutical and fine chemical applications. The glucansucrases produced by Streptococcus sp. were extensively studied on account of their major role in the formation of dental caries <Cite>Sidebotham1974 Monchois 1999</Cite>.

Depending on their specificity, glucansucrases catalyze the formation of linear as well as branched a-D-glucan chains with various types of glycosidic linkages, namely a-1,2; a-1,3; a-1,4; and/or a-1,6 <cite>Sidebotham1974 Andre2010 Jeanes1954</Cite>. They are classified by the nomenclature Committee of the International Union of Biochemistry and Molecular Biology on the basis of the reaction catalyzed and the specificity ; dextransucrase (sucrose:1,6-a-D-glucosyltransferase; EC 2.4.1.5), alternansucrase (sucrose:1,6(1,3)-a-D-glucan-6(3)-a-D-glucosyltransferase, EC2.4.1.140), mutansucrase (sucrose:1,3-a-D-glucan-3-a-D-glucosyltransferase; EC 2.4.1.5) and reuteransucrase (sucrose:1,4(6-a-D-glucan-4(6)-a-D-glucosyltransferase; EC 2.4.1.5). A wide range of a-D-glucans, varying in size, structure, degree of branching and spatial arrangements can thus be produced by GH70 family members <cite>Sidebotham1974 Monchois1999 Leemhuis2012 Andre2010</cite>.

Sucrose analogues such as a-D-glucopyranosyl fluoride, p-nitrophenyl a-D-glucopyranoside, a-D-glucopyranosyl a-L-sorofuranoside and lactulosucrose were also reported as D-glucopyranosyl donors <cite>Genghof1972 Figures1976 Binder1983</cite>. GH70 glucansucrases also transfer the D-glucosyl units from sucrose onto hydroxyl acceptor groups. A large variety of acceptors may be recognized by glucansucrases including carbohydrates, alcohols, polyols or flavonoids to yield oligosaccharides or gluco-conjugates <cite>Monchois1999 Leemhuis2012 Andre2010 Koepsell1953 Nakahara1995 Richard2003 Bertrand2006</cite>. The structure of the resultant glucosylated product is dependent upon the enzyme specificity.

Glucansucrases also catalyze glucosyl exchange between their glucan products in a reaction known as disproportionation <cite>Binderb1983</cite>. Of note, some members of GH70 family produced by Lb. reuteri sp. were also reported to be able to use maltooligosaccharides as the glucosyl donor and to catalyze its transfer to maltooligosaccharide acceptors via the formation of a-1,6 linkages, thus acting as 4,6-a-glucanotransferases and revealing additional evolutionary relations between GH 70 and 13 families <cite>Kralj2011 Dobruchowska2012 </cite>.

One glucansucrase was shown to possess two catalytically active domains acting in tandem <cite>Fabre2005</Cite>. This enzyme was shown to be secreted by Ln. mesenteroides NRRLB-1299 (reclassified as Ln. citreum). These domains work cooperatively to synthesize dextran with more than 20 % a-1,2 branched linkages and are both classified in the GH70 family. One domain is responsible for the synthesis of the a-1,6 linked dextran chain whereas the second one is specific for the catalysis of a-1,2 branch formation. The truncated form of this enzyme carrying only the second catalytic domain was named a-1,2 branching sucrase as it does not catalyse sucrose polymerization and shows transglucosylase activity only in the presence of sucrose and linear a-1,6 dextran <cite>Brison2012 </Cite>.

== Kinetics and Mechanism ==
Normal 0 21 false false false FR X-NONE X-NONE Enzymes from GH family 70 belong to the same GH H as clan GH family 13 and 77 enzymes. They employ an a-retaining mechanism. The transfer of the glucosyl unit proceeds through the formation of a b-glucosyl ester of an aspartate side chain, which was first isolated by sequencing peptides provided by rapid quenching of enzymic reactions with labeled sucrose and extracellular glucosyltransferases from S. sobrinus <cite>Mooser1989 Mooser1991</Cite>. Once the glucosyl-enzyme intermediate is formed, the glucosyl units originating from sucrose may be transferred onto either water (hydrolysis reaction), D-fructose released from sucrose cleavage (sucrose isomer formation) or onto the growing glucan chain (main reaction) <cite>Mooser1989 Mooser1991 Moulis2006 Vujicic-Zagar2010</Cite>. When acceptors are introduced into the reaction mixture, acceptor glucosylation occurs at the expense of polymer formation, the competition between the two reactions being controlled by acceptor recognition <cite>Koepsell1953</Cite>. Polymer extension proceeds from the non-reducing end <cite>Moulis2006</Cite> and involves a single active site as observed in the tertiary structures of GH70 enzymes <cite>Vujicic-Zagar2010 Ito2011</Cite>. Normal 0 21 false false false FR X-NONE X-NONE

The catalytic domain of family 70 enzymes is often flanked at the N- and/or C-termini by sequences containing a series of homologous repeating units that confer glucan binding ability <cite>Monchois1999 Leemhuis2012 Janecek2000</cite>. They are found in domain V (see structure scheme below) and have also been shown to influence polymer size, enzyme activity, specificity and processivity <cite>Monchois1999 Leemhuis2012 Moulis2006</cite>. However, their precise role at the molecular level is still not fully understood <cite>Vujicic-Zagar2010 Ito2011</Cite>.
== Catalytic Residues ==
Normal 0 21 false false false FR X-NONE X-NONE

Sequence analysis, secondary structure prediction and tertiary structure comparison with enzymes from GH Family 13 enabled the localization of a putative catalytic triad that is strictly conserved in family 70 and similar to that found in GH family 13 <cite>Vujicic-Zagar2010 Ito2011</Cite>. This triad is formed by an aspartate (nucleophile) corresponding to the residue identified by peptide sequencing <cite>Mooser1989 Mooser1991</Cite>, a glutamate (acid/base catalyst) and a second aspartic acid that is critical for transition state stabilization <cite>Vujicic-Zagar2010 Ito2011</Cite>. The putative role of these residues in catalysis was further supported by mutations and structural analyses <cite>Monchois1999 Leemhuis2012 Andre2010</cite>.

== Three-dimensional structures ==
Normal 0 21 false false false FR X-NONE X-NONE

The 3D structures of GTF180-DN dextransucrase from Lb reuteri 180 <cite>Vujicic-Zagar2010</Cite>, GTF-SI from S. mutans <cite>Ito2011</Cite> and a-1,2 branching sucrase (engineered from DSR-E dextransucrase from Ln. citreum NRRL B-1299) <cite>Brison2012</Cite>, all revealed a unique fold organized as five distinct domains, named C, A, B, IV and V, and made up of peptide segments that are not consecutively arranged along the peptide chain. The catalytic domain of GH70 glucansucrases consists of a (b/a)8 barrel resembling that of family 13 enzymes but formed by sequences that have undergone circular permutation compared with the GH13 family domains <cite>Vujicic-Zagar2010 MacGregor1996</Cite>. The 3D structures of complexes with sucrose, maltose and acarbose enabled the mapping of the active site and the identification of some determinants of GH70 enzyme product specificity.

Normal 0 21 false false false FR X-NONE X-NONE

Available structures:

GTF180-DN (dextransucrase from Lb reuteri 180) : 3KLK, 3KLL, 3HZ3 <cite>Vujicic-Zagar2010</Cite>

GTF-SI (mutansucrase from S. mutans : 3AIE, 3AIC, 3AIB <cite>Ito2011</Cite>

GBD-CD2 (a-1,2 branching sucrase) : 3TTO <cite>Ito2011</Cite>
== Family Firsts ==
Normal 0 21 false false false FR X-NONE X-NONE

First stereochemistry determination : The stereochemistry was directly linked to the discovery of the enzyme from Ln. mesenteroides catalyzing dextran synthesis from sucrose by Hehre <cite>Hehre1941</Cite>

First amino acid sequences: Those of GTF-B from S. mutans and GTF-I from S. sobrinus Mfe28 simultaneously reported in two companion articles <cite>Shiroza1987 Ferretti1987</cite>

First catalytic nucleophile identification : identified first in Streptococcus sobrinus glucansucrase <cite>Mooser1989 Mooser1991</Cite>

First general acid/base residue identification:

On the basis of sequence alignments and secondary structure <cite>MacGregor1996 </cite>.

On the basis of 3D-structure <cite>Vujicic-Zagar2010 Pijning2008 </Cite>

First 3-D structure

The first 3-D structure for GH70 members was that of the GTF180-DN dextransucrase from Lb reuteri <cite>Vujicic-Zagar2010 Pijning2008 </Cite>

== References ==
Normal 0 21 false false false FR X-NONE X-NONE

<biblio>

#Sidebotham1974 pmid=4157174

#Monchois1999 pmid= 10234842

#Leemhuis2012 pmid= 22796091

#Andre2010 pmid= 21626747

#Hehre1941 pmid=17775949

#Hehre1942 pmid=19871188

#Jeanes1954 Jeanes A, Haynes WC, Wilham CA, Rankin JC, Melvin EH, Austin MJ, Cluskey JE,Fisher BE, Tsuchiya HM, Rist CE Characterization and classification of dextrans from 96 strains of bacteria. J Am Chem Soc 1954; 76(20) 5041-5052. Doi: 10.1021/ja01649a011

#Genghof1972 pmid=5057594

#Figures1976 pmid=947539

#Binder1983 pmid=6671201

#Koepsell1953 pmid=13034840

#Nakahara1995 pmid=16535083

#Richard2003 pmid=12681910

#Bertrand2006 pmid=16530175

#Binderb1983 pmid=6671200

#Kralj2011 pmid=21948833

#Dobruchowska2012 pmid=22138321

#Fabre2005 pmid=15601714

#Brison2012 pmid=22262856

#Mooser1989 pmid=2523727

#Mooser1991 pmid=1827439

#Moulis2006 pmid=16864576

#Vujicic-Zagar2010 pmid=16880540

#Ito2011 pmid=21354427

#Janecek2000 pmid=11040428

#MacGregor1996 pmid = 8557114

#Shiroza1987 pmid=3040685

#Ferretti1987 pmid= 3040686

#Pijning2008 Pijning T, Vujicic-Zagar A, Kralj S, Eeuwema W, Dijkhuizen L, Dijkstra, BW Biochemical and crystallographic characterization of a glucansucrase from Lactobacillus reuteri 180. Biocat Biotrans 2008; 26 (1-2) 12-17 DOI: 10.1080/10242420701789163

</biblio>
[[Category:Glycoside Hydrolase Families|GH070]]

Glycoside Hydrolase Family 70

2012-08-21T15:38:15Z

Magali Remaud-Simeon:

{{UnderConstruction}}
* [[Author]]:
* [[Responsible Curator]]: ^^^Magali Remaud-Simeon^^^
----


<div style="float:right">
{| {{Prettytable}}
|-
|{{Hl2}} colspan="2" align="center" |'''Glycoside Hydrolase Family GH70'''
|-
|'''Clan'''
|GH-H
|-
|'''Mechanism'''
|retaining
|-
|'''Active site residues'''
|known/not known
|-
|{{Hl2}} colspan="2" align="center" |'''CAZy DB link'''
|-
| colspan="2" |{{CAZyDBlink}}GH70.html
|}
</div>


== Substrate specificities ==
Normal 0 21 false false false FR X-NONE X-NONE
Normal 0 21 false false false FR X-NONE X-NONE

GH 70 family enzymes are transglucosylases produced by lactic acid bacteria from Streptococcus, Leuconostoc, Weisella or Lactobacillus genera. Together with the GH 13 and GH77 enzymes, they form the clan GH-H.

Most of the enzymes classified in this family use sucrose as the D-glucopyranosyl donor to synthesize a-D-glucans of high molecular mass (>106 Da) with the concomitant release of D-fructose. They are also referred to as glucosyltransferases (GTF) or glucansucrases (GS) <cite>Sidebotham1974 Monchois1999 Leemhuis2012 Andre2010</cite>. The first glucansucrase was isolated from sucrose-broth cultures of a strain of Ln. mesenteroides <Cite>Hehre1941 Hehre1042</Cite>. The enzyme was shown to synthesize water-soluble dextran (a-1,6 linked D-glucan) from sucrose alone. Dextran from Ln. mesenteroides sp. was the first microbial polysaccharide to be commercialized and used for pharmaceutical and fine chemical applications. The glucansucrases produced by Streptococcus sp. were extensively studied on account of their major role in the formation of dental caries <Cite>Sidebotham1974 Monchois 1999</Cite>.

Depending on their specificity, glucansucrases catalyze the formation of linear as well as branched a-D-glucan chains with various types of glycosidic linkages, namely a-1,2; a-1,3; a-1,4; and/or a-1,6 <cite>Sidebotham1974 Andre2010 Jeanes1954</Cite>. They are classified by the nomenclature Committee of the International Union of Biochemistry and Molecular Biology on the basis of the reaction catalyzed and the specificity ; dextransucrase (sucrose:1,6-a-D-glucosyltransferase; EC 2.4.1.5), alternansucrase (sucrose:1,6(1,3)-a-D-glucan-6(3)-a-D-glucosyltransferase, EC2.4.1.140), mutansucrase (sucrose:1,3-a-D-glucan-3-a-D-glucosyltransferase; EC 2.4.1.5) and reuteransucrase (sucrose:1,4(6-a-D-glucan-4(6)-a-D-glucosyltransferase; EC 2.4.1.5). A wide range of a-D-glucans, varying in size, structure, degree of branching and spatial arrangements can thus be produced by GH70 family members <cite>Sidebotham1974 Monchois1999 Leemhuis2012 Andre2010</cite>.

Sucrose analogues such as a-D-glucopyranosyl fluoride, p-nitrophenyl a-D-glucopyranoside, a-D-glucopyranosyl a-L-sorofuranoside and lactulosucrose were also reported as D-glucopyranosyl donors <cite>Genghof1972 Figures1976 Binder1983<cite>. GH70 glucansucrases also transfer the D-glucosyl units from sucrose onto hydroxyl acceptor groups. A large variety of acceptors may be recognized by glucansucrases including carbohydrates, alcohols, polyols or flavonoids to yield oligosaccharides or gluco-conjugates <cite>Monchois1999 Leemhuis2012 Andre2010 Koepsell1953 Nakahara1995 Richard2003 Bertrand2006</cite>. The structure of the resultant glucosylated product is dependent upon the enzyme specificity.

Glucansucrases also catalyze glucosyl exchange between their glucan products in a reaction known as disproportionation <cite>Binderb1983</cite>. Of note, some members of GH70 family produced by Lb. reuteri sp. were also reported to be able to use maltooligosaccharides as the glucosyl donor and to catalyze its transfer to maltooligosaccharide acceptors via the formation of a-1,6 linkages, thus acting as 4,6-a-glucanotransferases and revealing additional evolutionary relations between GH 70 and 13 families <cite>Kralj2011 Dobruchowska2012 </cite>.

One glucansucrase was shown to possess two catalytically active domains acting in tandem <cite>Fabre2005</Cite>. This enzyme was shown to be secreted by Ln. mesenteroides NRRLB-1299 (reclassified as Ln. citreum). These domains work cooperatively to synthesize dextran with more than 20 % a-1,2 branched linkages and are both classified in the GH70 family. One domain is responsible for the synthesis of the a-1,6 linked dextran chain whereas the second one is specific for the catalysis of a-1,2 branch formation. The truncated form of this enzyme carrying only the second catalytic domain was named a-1,2 branching sucrase as it does not catalyse sucrose polymerization and shows transglucosylase activity only in the presence of sucrose and linear a-1,6 dextran <cite>Brison2012 </Cite>.

== Kinetics and Mechanism ==
Normal 0 21 false false false FR X-NONE X-NONE Enzymes from GH family 70 belong to the same GH H as clan GH family 13 and 77 enzymes. They employ an a-retaining mechanism. The transfer of the glucosyl unit proceeds through the formation of a b-glucosyl ester of an aspartate side chain, which was first isolated by sequencing peptides provided by rapid quenching of enzymic reactions with labeled sucrose and extracellular glucosyltransferases from S. sobrinus <cite>Mooser1989 Mooser1991</Cite>. Once the glucosyl-enzyme intermediate is formed, the glucosyl units originating from sucrose may be transferred onto either water (hydrolysis reaction), D-fructose released from sucrose cleavage (sucrose isomer formation) or onto the growing glucan chain (main reaction) <cite>Mooser1989 Mooser1991 Moulis2006 Vujicic-Zagar2010</Cite>. When acceptors are introduced into the reaction mixture, acceptor glucosylation occurs at the expense of polymer formation, the competition between the two reactions being controlled by acceptor recognition <cite>Koepsell1953</Cite>. Polymer extension proceeds from the non-reducing end <cite>Moulis2006</Cite> and involves a single active site as observed in the tertiary structures of GH70 enzymes <cite>Vujicic-Zagar2010 Ito2011</Cite>. Normal 0 21 false false false FR X-NONE X-NONE

The catalytic domain of family 70 enzymes is often flanked at the N- and/or C-termini by sequences containing a series of homologous repeating units that confer glucan binding ability <cite>Monchois1999 Leemhuis2012 Janecek2000</cite>. They are found in domain V (see structure scheme below) and have also been shown to influence polymer size, enzyme activity, specificity and processivity <cite>Monchois1999 Leemhuis2012 Moulis2006</cite>. However, their precise role at the molecular level is still not fully understood <cite>Vujicic-Zagar2010 Ito2011</Cite>.
== Catalytic Residues ==
Normal 0 21 false false false FR X-NONE X-NONE

Sequence analysis, secondary structure prediction and tertiary structure comparison with enzymes from GH Family 13 enabled the localization of a putative catalytic triad that is strictly conserved in family 70 and similar to that found in GH family 13 <cite>Vujicic-Zagar2010 Ito2011</Cite>. This triad is formed by an aspartate (nucleophile) corresponding to the residue identified by peptide sequencing <cite>Mooser1989 Mooser1991</Cite>, a glutamate (acid/base catalyst) and a second aspartic acid that is critical for transition state stabilization <cite>Vujicic-Zagar2010 Ito2011</Cite>. The putative role of these residues in catalysis was further supported by mutations and structural analyses <cite>Monchois1999 Leemhuis2012 Andre2010</cite>.

== Three-dimensional structures ==
Normal 0 21 false false false FR X-NONE X-NONE

The 3D structures of GTF180-DN dextransucrase from Lb reuteri 180 <cite>Vujicic-Zagar2010</Cite>, GTF-SI from S. mutans <cite>Ito2011</Cite> and a-1,2 branching sucrase (engineered from DSR-E dextransucrase from Ln. citreum NRRL B-1299) <cite>Brison2012<Cite>, all revealed a unique fold organized as five distinct domains, named C, A, B, IV and V, and made up of peptide segments that are not consecutively arranged along the peptide chain. The catalytic domain of GH70 glucansucrases consists of a (b/a)8 barrel resembling that of family 13 enzymes but formed by sequences that have undergone circular permutation compared with the GH13 family domains <cite>Vujicic-Zagar2010 MacGregor1996</Cite>. The 3D structures of complexes with sucrose, maltose and acarbose enabled the mapping of the active site and the identification of some determinants of GH70 enzyme product specificity.

Normal 0 21 false false false FR X-NONE X-NONE

Available structures:

GTF180-DN (dextransucrase from Lb reuteri 180) : 3KLK, 3KLL, 3HZ3 <cite>Vujicic-Zagar2010</Cite>

GTF-SI (mutansucrase from S. mutans : 3AIE, 3AIC, 3AIB <cite>Ito2011</Cite>

GBD-CD2 (a-1,2 branching sucrase) : 3TTO <cite>Ito2011</Cite>
== Family Firsts ==
Normal 0 21 false false false FR X-NONE X-NONE

First stereochemistry determination : The stereochemistry was directly linked to the discovery of the enzyme from Ln. mesenteroides catalyzing dextran synthesis from sucrose by Hehre <cite>Hehre1941</Cite>

First amino acid sequences: Those of GTF-B from S. mutans and GTF-I from S. sobrinus Mfe28 simultaneously reported in two companion articles <cite>Shiroza1987 Ferretti1987</cite>

First catalytic nucleophile identification : identified first in Streptococcus sobrinus glucansucrase <cite>Mooser1989 Mooser1991</Cite>

First general acid/base residue identification:

On the basis of sequence alignments and secondary structure <cite>MacGregor1996 </cite>.

On the basis of 3D-structure <cite>Vujicic-Zagar2010 Pijning2008 </Cite>

First 3-D structure

The first 3-D structure for GH70 members was that of the GTF180-DN dextransucrase from Lb reuteri <cite>Vujicic-Zagar2010 Pijning2008 <Cite>

== References ==
Normal 0 21 false false false FR X-NONE X-NONE

<biblio>

#Sidebotham1974 pmid=4157174

#Monchois1999 pmid= 10234842

#Leemhuis2012 pmid= 22796091

#Andre2010 pmid= 21626747

#Hehre1941 pmid=17775949

#Hehre1942 pmid=19871188

#Jeanes1954 Jeanes A, Haynes WC, Wilham CA, Rankin JC, Melvin EH, Austin MJ, Cluskey JE,Fisher BE, Tsuchiya HM, Rist CE Characterization and classification of dextrans from 96 strains of bacteria. J Am Chem Soc 1954; 76(20) 5041-5052. Doi: 10.1021/ja01649a011

#Genghof1972 pmid=5057594

#Figures1976 pmid=947539

#Binder1983 pmid=6671201

#Koepsell1953 pmid=13034840

#Nakahara1995 pmid=16535083

#Richard2003 pmid=12681910

#Bertrand2006 pmid=16530175

#Binderb1983 pmid=6671200

#Kralj2011 pmid=21948833

#Dobruchowska2012 pmid=22138321

#Fabre2005 pmid=15601714

#Brison2012 pmid=22262856

#Mooser1989 pmid=2523727

#Mooser1991 pmid=1827439

#Moulis2006 pmid=16864576

#Vujicic-Zagar2010 pmid=16880540

#Ito2011 pmid=21354427

#Janecek2000 pmid=11040428

#MacGregor1996 pmid = 8557114

#Shiroza1987 pmid=3040685

#Ferretti1987 pmid= 3040686

#Pijning2008 Pijning T, Vujicic-Zagar A, Kralj S, Eeuwema W, Dijkhuizen L, Dijkstra, BW Biochemical and crystallographic characterization of a glucansucrase from Lactobacillus reuteri 180. Biocat Biotrans 2008; 26 (1-2) 12-17 DOI: 10.1080/10242420701789163

</biblio>
[[Category:Glycoside Hydrolase Families|GH070]]

User:Magali Remaud-Simeon

2012-08-21T13:11:00Z

Magali Remaud-Simeon:

800x600 Normal 0 21 false false false FR X-NONE X-NONE MicrosoftInternetExplorer4

Magali Remaud-Simeon graduated from the National Institute of Applied Science of Toulouse in 1985 and received her PhD in 1988. Then she was as Post-Doctotal Fellow at the University of Pensylvania where she worked with Prof D. Graves in the department of Chemical and Biomolecular Engineering. From 1990 to 2000, she was an associate professor at the Institute of Technology of the University of Toulouse in the department of Applied Biology. She joined the group of Biocatalysis of Prof. P. MONSAN at the "laboratoire d'Ingénierie des systèmes et des procédés" in 1994. Since 2001, she is a professor at the National Institute of Applied Science of Toulouse. As the head of the Enzyme Molecular Engineering and Catalysis group since 2001, she focuses her research activities on enzyme engineering for white biotechnology, green chemistry, Food/Feed industries and synthetic biology. Her areas of interest cover enzyme structure/activity relationship studies, kinetic resolution, evolution combining both rational and combinatorial approaches, and applications to the synthesis of new polysaccharides, oligosaccharides, glycoonjugates, esters and enantiopure compounds. She has been working on glucansucrases from GH family 70 and 13 since 1985. With her collaborators, she has investigated the mechanism of dextran, alternan and amylose biosynthesis by dextransucrase, alternansucrase and amylosucrase, respectively. Her work is currently focused on the search and generation of enzymes displaying new specificities and improved properties towards unnatural substrates.

E-mail: magali.remaud@insa-toulouse.fr http://www.lisbp.insa-toulouse.fr

Glucansucrases from GH 70 Family
Normal 0 21 false false false FR X-NONE X-NONE

André I, Potocki-Véronèse G, Morel S, Monsan P, Remaud-Siméon M. 2010. Sucrose-acting transglucosidases for biocatalysis. Top. Curr. Chem. carbohydrates in sustainable development II. Eds Rauter AP, Vogel P, Queneau Y. Vol. 294, pp 25-48 PMID:21626747

Normal 0 21 false false false FR X-NONE X-NONE

Fabre E, Bozonnet S, Arcache A, Willemot RM, Vignon M, Monsan P, Remaud-Simeon, M. Role of the two catalytic domains of DSR-E dextransucrase and their involvement in the formation of highly alpha-1,2 branched dextran. J Bacteriol 2005 Jan; 187(1) 296-303. doi: 10.1128/JB.187.1.296-303.2005 PMID:15601714

Normal 0 21 false false false FR X-NONE X-NONE

Moulis C, Joucla G, Harrison D, Fabre E, Potocki-Veronese G, Monsan P, Remaud-Simeon M. Understanding the polymerization mechanism of glycoside-hydrolase family 70 glucansucrases. J Biol. Chem 2006 Oct 20; 281 (42) 31254-31267. DOI: 10.1074/jbc.M604850200 PMID:16864576

Brison Y, Pijning T, Malbert Y, Fabre E, Morel S, Potocki-Veronese G, Monsan P, Tranier S, Remaud-Simeon M, Dijkstra BW. Functional and Structural Characterization of alpha-(1 -> 2) Branching Sucrase Derived from DSR-E Glucansucrase. J Biol Chem 2012 March 9; 287(11) 7915-7924. doi: 10.1074/jbc.M111.305078 PMID:22262856

Glucansucrases from GH13 Family
Normal 0 21 false false false FR X-NONE X-NONE

Guérin F, Barbe S., Pizzut-Serin S, Potocki-Véronèse G, Guieysse D, Guillet V, Monsan P, Mourey L, Remaud-Simeon M, André I and Tranier S.. Structural investigation of the thermostability and product specificity of amylosucrase from the bacterium Deinococcus geothermalis. J. Biol Chem 2012; 287(9):6642-6654

Champion E, André I, Moulis C, Boutet J, Descroix K, Morel S, Monsan P, Mulard LA, Remaud-Simeon M. 2009a. Design of alpha-transglucosidases of controlled specificity for programmed chemoenzymatic synthesis of antigenic oligosaccharides. J Am Chem Soc 2009; 131(21):7379-89

Albenne C, Skov LK, Mirza O, Gajhede M, Feller G, D’Amico S, Andre G, Potocki-Véronèse G, Van Der Veen B, Monsan P, Remaud-Simeon M. Molecular basis of the amylose-like polymer formation catalysed by Neisseria polysaccharea amylosucrase. J Biol Chem 2004; 279, 726-734.
Normal 0 21 false false false FR X-NONE X-NONE

User:Magali Remaud-Simeon

2012-08-21T12:37:30Z

Magali Remaud-Simeon: Created page with " 800x600 Normal 0 21 false false false FR X-NONE X-NONE MicrosoftInternetExplorer4 Magali Remaud-Siméon graduated fro..."

800x600 Normal 0 21 false false false FR X-NONE X-NONE MicrosoftInternetExplorer4

Magali Remaud-Siméon graduated from the National Institute of Applied Science of Toulouse in 1985 and received her PhD in 1988. Then she was as Post-Doctotal Fellow at the University of Pensylvania where she worked with Prof D. Graves in the department of Chemical and Biomolecular Engineering. From 1990 to 2000, she was an associate professor at the Institute of Technology of the University of Toulouse in the department of Applied Biology. Since 2001, she is a professor at the National Institute of Applied Science of Toulouse. As the head of the Enzyme Molecular Engineering and Catalysis group since 2001, she focuses her research activities on enzyme engineering for white biotechnology, green chemistry, Food/Feed industries and synthetic biology. Her areas of interest cover enzyme structure/activity relationship studies, kinetic resolution, evolution combining both rational and combinatorial approaches, and applications to the synthesis of new polysaccharides, oligosaccharides, glycoonjugates, esters and enantiopure compounds. She has been working on glucansucrases from GH family 70 and 13 since 1985. With her collaborators, she has elucidated the mechanism of dextran, alternan and amylose biosynthesis by dextransucrase, alternansucrase and amylosucrase, respectively. Her work is currently focused on the search and generation of enzymes displaying new specificities and improved properties towards unnatural substrate.