Glycoside Hydrolase Family 95 - Revision history

Harry Brumer: Text replacement - "\^\^\^(.*)\^\^\^" to "$1"

2021-12-18T21:16:07Z

Text replacement - "\^\^\^(.*)\^\^\^" to "$1"

Spencer Williams at 23:18, 11 May 2016

2016-05-11T23:18:24Z

Spencer Williams: /* Three-dimensional structures */

2016-05-11T23:18:00Z

Three-dimensional structures

Spencer Williams at 23:17, 11 May 2016

2016-05-11T23:17:00Z

Spencer Williams at 11:31, 12 May 2011

2011-05-12T11:31:12Z

Takane Katayama at 00:28, 9 May 2011

2011-05-09T00:28:58Z

Shinya Fushinobu at 15:57, 4 May 2011

2011-05-04T15:57:02Z

Harry Brumer: added EC link, minor text improvements

2011-05-04T09:33:45Z

added EC link, minor text improvements

Takane Katayama at 08:37, 3 May 2011

2011-05-03T08:37:40Z

Takane Katayama at 08:31, 3 May 2011

2011-05-03T08:31:51Z

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 <!-- RESPONSIBLE CURATORS: Please replace the {{UnderConstruction}} tag below with {{CuratorApproved}} when the page is ready for wider public consumption -->
 {{CuratorApproved}}
-* [[Author]]: ^^^Takane Katayama^^^, ^^^Spencer Williams^^^
+* [[Author]]: [[User:Takane Katayama|Takane Katayama]], [[User:Spencer Williams|Spencer Williams]]
-* [[Responsible Curator]]:  ^^^Takane Katayama^^^
+* [[Responsible Curator]]:  [[User:Takane Katayama|Takane Katayama]]
 ----

@@ Line 1: / Line 1: @@
 <!-- RESPONSIBLE CURATORS: Please replace the {{UnderConstruction}} tag below with {{CuratorApproved}} when the page is ready for wider public consumption -->
 {{CuratorApproved}}
-* [[Author]]: ^^^Takane Katayama^^^
+* [[Author]]: ^^^Takane Katayama^^^, ^^^Spencer Williams^^^
 * [[Responsible Curator]]:  ^^^Takane Katayama^^^
 ----

@@ Line 40: / Line 40: @@
 == Three-dimensional structures ==
-The first solved 3D structure was of the catalytic domain (aa. 577-1474 of 1959) of ''Bb''AfcA (PDB ID [{{PDBlink}}2eab 2eab] WT in apo form, PDB ID [{{PDBlink}}2eac 2eac] WT in compex with deoxyfuconojirimycin, PDB ID [{{PDBlink}}2ead 2ead] E566A in complex with 2'-fucosyllactose, PDB ID [{{PDBlink}}2eae 2eae] D766A in complex with fucose and lactose) <cite>Nagae2007</cite>. The catalytic domain adopts an (&alpha;/&alpha;)<sub>6</sub>-barrel fold that is quite similar to those of [[clan]] GH-L ([[GH15]], [[GH65]], and [[GH125]]) and [[GH94]]. The members of [[clan]] GH-L and GH95 act on &alpha;-linkages, whereas [[GH94]] acts on &beta;-linkage. An X-ray structure of a ''Bacteroides ovatus'' &alpha;-L-galactosidase in complex with L-galactose highlighted Thr370 as a key residue interacting with the 6-hydroxyl group, which is present as His in 1,2-&alpha;-L-fucosidases such as ''Bb'', and which may determine specificity for L-galactose versus L-fucose <cite>Rogowski2015</cite>.
+The first solved 3D structure was of the catalytic domain (aa. 577-1474 of 1959) of ''Bb''AfcA (PDB ID [{{PDBlink}}2eab 2eab] WT in apo form, PDB ID [{{PDBlink}}2eac 2eac] WT in compex with deoxyfuconojirimycin, PDB ID [{{PDBlink}}2ead 2ead] E566A in complex with 2'-fucosyllactose, PDB ID [{{PDBlink}}2eae 2eae] D766A in complex with fucose and lactose) <cite>Nagae2007</cite>. The catalytic domain adopts an (&alpha;/&alpha;)<sub>6</sub>-barrel fold that is quite similar to those of [[clan]] GH-L ([[GH15]], [[GH65]], and [[GH125]]) and [[GH94]]. The members of [[clan]] GH-L and GH95 act on &alpha;-linkages, whereas [[GH94]] acts on &beta;-linkage. An X-ray structure of a ''Bacteroides ovatus'' &alpha;-L-galactosidase in complex with L-galactose highlighted Thr370 as a key residue interacting with the 6-hydroxyl group, which is a His residue in 1,2-&alpha;-L-fucosidases such as ''Bb'', and which may determine specificity for L-galactose versus L-fucose <cite>Rogowski2015</cite>.
 == Family Firsts ==
 ;First stereochemistry determination:1,2-&alpha;-L-Fucosidase from ''Bifidobacterium bifidum'', determined by <sup>1</sup>H-NMR using 2'-fucosyllactose as a substrate <cite>Katayama2004</cite>.

@@ Line 29: / Line 29: @@
 == Substrate specificities ==
-[[Glycoside hydrolases]] of GH95 are exclusively 1,2-&alpha;-L-fucosidases (EC [{{EClink}}3.2.1.63 3.2.1.63]) that hydrolyze Fuc&alpha;1-2Gal linkages attached at the non-reducing ends of oligosaccharides <cite>Katayama2004 Altmann2008</cite>.  Such structures are found in human milk oligosaccharides (2'-fucosyllactose; Fuc&alpha;1-2Gal&beta;1-4Glc) and blood group glycoconjugates (ABO and Lewis antigens) and are also found as branching residues on the plant polysaccharide xyloglucan (see below) <cite>Altmann2008</cite>.  An 1,2-&alpha;-L-fucosidase from [http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?id=1681 ''Bifidobacterium bifidum''] (''Bb''AfcA) cannot hydrolyze the fucosyl linkage when the Gal residue is further modified, i.e. the enzyme does not act on blood group A- and B-trisaccharides (see <cite>Liu2007</cite> for structures). 3-Fucosyllactose, Gal&beta;1-4(Fuc&alpha;1-3)Glc, is slightly hydrolyzed by the ''Bb''AfcA.  1,2-&alpha;-L-Fucosidases from [http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?id=3702 ''Arabidopsis thaliana''] and [http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?id=4690''Lilium longiflorum''] (lily) can liberate L-fucose from xyloglucan fragment XXFG [Xyl&alpha;1-6Glc&beta;1-4(Xyl&alpha;1-6)Glc&beta;1-4(Fuc&alpha;1-2Gal&beta;1-2Xyl&alpha;1-6)Glc&beta;1-4Glc] as well as 2'-fucosyllactose, but does not liberate L-fucose from 3-fucosyllactose. Both ''Bb''AfcA and the plant enzymes do not act on other linkages and artificial substrates such as 4'-nitrophenyl-&alpha;-L-fucoside.
+[[Glycoside hydrolases]] of GH95 includes 1,2-&alpha;-L-fucosidases (EC [{{EClink}}3.2.1.63 3.2.1.63]) that hydrolyze &alpha;-Fuc-1,2-Gal linkages attached at the non-reducing ends of oligosaccharides <cite>Katayama2004 Altmann2008</cite>, and 1,2-&alpha;-L-galactosidases that hydrolyze L-galactoside linkages in arabinoxylans <cite>Rogowski2015</cite>.  &alpha;-Fuc-1,2-Gal linkages are found in human milk oligosaccharides (2'-fucosyllactose; Fuc&alpha;1-2Gal&beta;1-4Glc) and blood group glycoconjugates (ABO and Lewis antigens) and are also found as branching residues on the plant polysaccharide xyloglucan (see below) <cite>Altmann2008</cite>.  &alpha;-L-Gal-1,2-Xyl linkages are present on side branches on corn glucuronoarabinoxylan <cite>Rogowski2015</cite>. An 1,2-&alpha;-L-fucosidase from [http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?id=1681 ''Bifidobacterium bifidum''] (''Bb''AfcA) cannot hydrolyze the fucosyl linkage when the Gal residue is further modified, i.e. the enzyme does not act on blood group A- and B-trisaccharides (see <cite>Liu2007</cite> for structures). 3-Fucosyllactose, Gal&beta;1-4(Fuc&alpha;1-3)Glc, is slightly hydrolyzed by the ''Bb''AfcA.  1,2-&alpha;-L-Fucosidases from [http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?id=3702 ''Arabidopsis thaliana''] and [http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?id=4690''Lilium longiflorum''] (lily) can liberate L-fucose from xyloglucan fragment XXFG [Xyl&alpha;1-6Glc&beta;1-4(Xyl&alpha;1-6)Glc&beta;1-4(Fuc&alpha;1-2Gal&beta;1-2Xyl&alpha;1-6)Glc&beta;1-4Glc] as well as 2'-fucosyllactose, but does not liberate L-fucose from 3-fucosyllactose. Both ''Bb''AfcA and the plant enzymes do not act on other linkages and artificial substrates such as 4'-nitrophenyl-&alpha;-L-fucoside.
 == Kinetics and Mechanism ==
@@ Line 40: / Line 40: @@
 == Three-dimensional structures ==
-The first solved 3D structure was of the catalytic domain (aa. 577-1474 of 1959) of ''Bb''AfcA (PDB ID [{{PDBlink}}2eab 2eab] WT in apo form, PDB ID [{{PDBlink}}2eac 2eac] WT in compex with deoxyfuconojirimycin, PDB ID [{{PDBlink}}2ead 2ead] E566A in complex with 2'-fucosyllactose, PDB ID [{{PDBlink}}2eae 2eae] D766A in complex with fucose and lactose) <cite>Nagae2007</cite>. The catalytic domain adopts an (&alpha;/&alpha;)<sub>6</sub>-barrel fold that is quite similar to those of [[clan]] GH-L ([[GH15]], [[GH65]], and [[GH125]]) and [[GH94]]. The members of [[clan]] GH-L and GH95 act on &alpha;-linkages, whereas [[GH94]] acts on &beta;-linkage.
+The first solved 3D structure was of the catalytic domain (aa. 577-1474 of 1959) of ''Bb''AfcA (PDB ID [{{PDBlink}}2eab 2eab] WT in apo form, PDB ID [{{PDBlink}}2eac 2eac] WT in compex with deoxyfuconojirimycin, PDB ID [{{PDBlink}}2ead 2ead] E566A in complex with 2'-fucosyllactose, PDB ID [{{PDBlink}}2eae 2eae] D766A in complex with fucose and lactose) <cite>Nagae2007</cite>. The catalytic domain adopts an (&alpha;/&alpha;)<sub>6</sub>-barrel fold that is quite similar to those of [[clan]] GH-L ([[GH15]], [[GH65]], and [[GH125]]) and [[GH94]]. The members of [[clan]] GH-L and GH95 act on &alpha;-linkages, whereas [[GH94]] acts on &beta;-linkage. An X-ray structure of a ''Bacteroides ovatus'' &alpha;-L-galactosidase in complex with L-galactose highlighted Thr370 as a key residue interacting with the 6-hydroxyl group, which is present as His in 1,2-&alpha;-L-fucosidases such as ''Bb'', and which may determine specificity for L-galactose versus L-fucose <cite>Rogowski2015</cite>.
 == Family Firsts ==
 ;First stereochemistry determination:1,2-&alpha;-L-Fucosidase from ''Bifidobacterium bifidum'', determined by <sup>1</sup>H-NMR using 2'-fucosyllactose as a substrate <cite>Katayama2004</cite>.
@@ Line 55: / Line 54: @@
 #Nagae2007 pmid=17459873
 #Liu2007 pmid=17401360
 </biblio>
 [[Category:Glycoside Hydrolase Families|GH095]]

@@ Line 29: / Line 29: @@
 == Substrate specificities ==
-This family exclusively contains 1,2-&alpha;-L-fucosidases (EC [{{EClink}}3.2.1.63 3.2.1.63]) that hydrolyze Fuc&alpha;1-2Gal linkages attached at the non-reducing ends of oligosaccharides <cite>Katayama2004 Altmann2008</cite>.  Such structures are found in human milk oligosaccharides (2'-fucosyllactose; Fuc&alpha;1-2Gal&beta;1-4Glc) and blood group glycoconjugates (ABO and Lewis antigens) and are also found as branching residues on the plant polysaccharide xyloglucan (see below) <cite>Altmann2008</cite>.  An 1,2-&alpha;-L-fucosidase from [http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?id=1681 ''Bifidobacterium bifidum''] (''Bb''AfcA) cannot hydrolyze the fucosyl linkage when the Gal residue is further modified, i.e. the enzyme does not act on blood group A- and B-trisaccharides (see <cite>Liu2007</cite> for structures). 3-Fucosyllactose, Gal&beta;1-4(Fuc&alpha;1-3)Glc, is slightly hydrolyzed by the ''Bb''AfcA.  1,2-&alpha;-L-Fucosidases from [http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?id=3702 ''Arabidopsis thaliana''] and [http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?id=4690''Lilium longiflorum''] (lily) can liberate L-fucose from xyloglucan fragment XXFG [Xyl&alpha;1-6Glc&beta;1-4(Xyl&alpha;1-6)Glc&beta;1-4(Fuc&alpha;1-2Gal&beta;1-2Xyl&alpha;1-6)Glc&beta;1-4Glc] as well as 2'-fucosyllactose, but does not liberate L-fucose from 3-fucosyllactose. Both ''Bb''AfcA and the plant enzymes do not act on other linkages and artificial substrates such as 4'-nitrophenyl-&alpha;-L-fucoside.
+[[Glycoside hydrolases]] of GH95 are exclusively 1,2-&alpha;-L-fucosidases (EC [{{EClink}}3.2.1.63 3.2.1.63]) that hydrolyze Fuc&alpha;1-2Gal linkages attached at the non-reducing ends of oligosaccharides <cite>Katayama2004 Altmann2008</cite>.  Such structures are found in human milk oligosaccharides (2'-fucosyllactose; Fuc&alpha;1-2Gal&beta;1-4Glc) and blood group glycoconjugates (ABO and Lewis antigens) and are also found as branching residues on the plant polysaccharide xyloglucan (see below) <cite>Altmann2008</cite>.  An 1,2-&alpha;-L-fucosidase from [http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?id=1681 ''Bifidobacterium bifidum''] (''Bb''AfcA) cannot hydrolyze the fucosyl linkage when the Gal residue is further modified, i.e. the enzyme does not act on blood group A- and B-trisaccharides (see <cite>Liu2007</cite> for structures). 3-Fucosyllactose, Gal&beta;1-4(Fuc&alpha;1-3)Glc, is slightly hydrolyzed by the ''Bb''AfcA.  1,2-&alpha;-L-Fucosidases from [http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?id=3702 ''Arabidopsis thaliana''] and [http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?id=4690''Lilium longiflorum''] (lily) can liberate L-fucose from xyloglucan fragment XXFG [Xyl&alpha;1-6Glc&beta;1-4(Xyl&alpha;1-6)Glc&beta;1-4(Fuc&alpha;1-2Gal&beta;1-2Xyl&alpha;1-6)Glc&beta;1-4Glc] as well as 2'-fucosyllactose, but does not liberate L-fucose from 3-fucosyllactose. Both ''Bb''AfcA and the plant enzymes do not act on other linkages and artificial substrates such as 4'-nitrophenyl-&alpha;-L-fucoside.
 == Kinetics and Mechanism ==
@@ Line 36: / Line 36: @@
 == Catalytic Residues ==
-GH95 enzymes are considered to employ a unique reaction mechanism, in which Asp-activated Asn acts as a general-base catalyst while the role of the general-acid catalyst is played by a canonical carboxylic residue, Glu. In ''Bb''AfcA, Glu566 and Asn423 have been identified as the general-acid and -base residues, respectively <cite>Nagae2007</cite>. Glu566 is hydrogen-bonded with Asn421, and this hydrogen bond is thought to be important in orienting the side chain of Glu566 toward the oxygen atom (O2) of the departing Gal. Asn423 is activated by the neighboring Asp766, and consequently activates a nucleophilic water molecule. This model (carboxylic acid-mediated activation of amido group) bears analogy to the substrate-assisted catalysis mechanism employed by members of [[GH18]], [[GH20]], and [[GH85]].
+GH95 enzymes are considered to employ a unique reaction mechanism, in which Asp-activated Asn acts as a [[general base]] catalyst while the role of the [[general acid]] catalyst is played by a canonical carboxylic residue, Glu. In ''Bb''AfcA, Glu566 and Asn423 have been identified as the [[general acid]] and [[general base]] residues, respectively <cite>Nagae2007</cite>. Glu566 is hydrogen-bonded with Asn421, and this hydrogen bond is thought to be important in orienting the side chain of Glu566 toward the oxygen atom (O2) of the departing Gal. Asn423 is activated by the neighboring Asp766, and consequently activates a nucleophilic water molecule. This model (carboxylic acid-mediated activation of amido group) bears some analogy to the [[neighboring group participation]] mechanism employed by members of [[GH18]], [[GH20]], [[GH25]], [[GH56]], [[GH84]] and [[GH85]].
 These four residues are invariable in the members of this family, and substitution with alanine or glycine diminishes activities by 1,000- to 10,000-fold<cite>Nagae2007</cite>.
 == Three-dimensional structures ==
-The first solved 3-D structure was the catalytic domain (aa. 577-1474 of 1959) of ''Bb''AfcA (PDB ID [{{PDBlink}}2eab 2eab] WT in apo form, PDB ID [{{PDBlink}}2eac 2eac] WT in compex with deoxyfuconojirimycin, PDB ID [{{PDBlink}}2ead 2ead] E566A in complex with 2'-fucosyllactose, PDB ID [{{PDBlink}}2eae 2eae] D766A in complex with fucose and lactose) <cite>Nagae2007</cite>. The catalytic domain adopts an (&alpha;/&alpha;)<sub>6</sub>-barrel fold that is quite similar to those of [[clan]] GH-L ([[GH15]], [[GH65]], and [[GH125]]) and [[GH94]]. The members of [[Clan]] GH-L and GH95 act on &alpha;-linkages, whereas [[GH94]] acts on &beta;-linkage.
+The first solved 3D structure was of the catalytic domain (aa. 577-1474 of 1959) of ''Bb''AfcA (PDB ID [{{PDBlink}}2eab 2eab] WT in apo form, PDB ID [{{PDBlink}}2eac 2eac] WT in compex with deoxyfuconojirimycin, PDB ID [{{PDBlink}}2ead 2ead] E566A in complex with 2'-fucosyllactose, PDB ID [{{PDBlink}}2eae 2eae] D766A in complex with fucose and lactose) <cite>Nagae2007</cite>. The catalytic domain adopts an (&alpha;/&alpha;)<sub>6</sub>-barrel fold that is quite similar to those of [[clan]] GH-L ([[GH15]], [[GH65]], and [[GH125]]) and [[GH94]]. The members of [[clan]] GH-L and GH95 act on &alpha;-linkages, whereas [[GH94]] acts on &beta;-linkage.
 == Family Firsts ==
 ;First stereochemistry determination:1,2-&alpha;-L-Fucosidase from ''Bifidobacterium bifidum'', determined by <sup>1</sup>H-NMR using 2'-fucosyllactose as a substrate <cite>Katayama2004</cite>.
 ;First molecular cloning:1,2-&alpha;-L-Fucosidase from ''Bifidobacterium bifidum'', by expression cloning using a genomic library conctructed in ''Escherichia coli'' <cite>Katayama2004</cite>.
-;First catalytic base identification:1,2-&alpha;-L-Fucosidase from ''Bifidobacterium bifidum'', by kinetic analysis and chemical rescue of the mutants <cite>Nagae2007</cite>.
+;First [[general base]] residue identification:1,2-&alpha;-L-Fucosidase from ''Bifidobacterium bifidum'', by kinetic analysis and chemical rescue of the mutants <cite>Nagae2007</cite>.
-;First catalytic acid residue identification:1,2-&alpha;-L-Fucosidase from ''Bifidobacterium bifidum'', by kinetic analysis of the mutant <cite>Nagae2007</cite>.
+;First [[general acid]] residue identification:1,2-&alpha;-L-Fucosidase from ''Bifidobacterium bifidum'', by kinetic analysis of the mutant <cite>Nagae2007</cite>.
 ;First 3-D structure:The catalytic domain of 1,2-&alpha;-L-fucosidase from ''Bifidobacterium bifidum'', wild-type enzyme in apo-form, wild-type enzyme in complex with deoxyfuconojirimycin, E566A in complex with 2'-fucosyllactose, D766A in complex with fucose and lactose <cite>Nagae2007</cite>.

@@ Line 29: / Line 29: @@
 == Substrate specificities ==
-This family exclusively contains 1,2-&alpha;-L-fucosidases (EC 3.2.1.63) that hydrolyze Fuc&alpha;1-2Gal linkages attached at the non-reducing ends of oligosaccharides <cite>Katayama2004 Altmann2008</cite>.  Such structures are found in human milk oligosaccharides (2'-fucosyllactose; Fuc&alpha;1-2Gal&beta;1-4Glc) and blood group glycoconjugates (ABO and Lewis antigens) and are also found as branching residues on the plant polysaccharide xyloglucan (see below) <cite>Altmann2008</cite>.  1,2-&alpha;-L-Fucosidase from ''Bifidobacterium bifidum'' (''Bb''AfcA) cannot hydrolyze the fucosyl linkage when the Gal residue is further modified, i.e. the enzyme do not act on blood group A- and B-trisaccharides. 3-Fucosyllactose, Gal&beta;1-4(Fuc&alpha;1-3)Glc, is slightly hydrolyzed by the enzyme.  1,2-&alpha;-L-Fucosidases from ''Arabidopsis thaliana'' and ''Lilium longiflorum''(lily) can liberate L-fucose from xyloglucan fragment XXFG [Xyl&alpha;1-6Glc&beta;1-4(Xyl&alpha;1-6)Glc&beta;1-4(Fuc&alpha;1-2Gal&beta;1-2Xyl&alpha;1-6)Glc&beta;1-4Glc] as well as 2'-fucosyllactose, but does not liberate L-fucose from 3-fucosyllactose. Both ''Bb''AfcA and the plant enzymes do not act on the other linkages and artificial substrates such as pNP-Fuc.
+This family exclusively contains 1,2-&alpha;-L-fucosidases (EC [{{EClink}}3.2.1.63 3.2.1.63]) that hydrolyze Fuc&alpha;1-2Gal linkages attached at the non-reducing ends of oligosaccharides <cite>Katayama2004 Altmann2008</cite>.  Such structures are found in human milk oligosaccharides (2'-fucosyllactose; Fuc&alpha;1-2Gal&beta;1-4Glc) and blood group glycoconjugates (ABO and Lewis antigens) and are also found as branching residues on the plant polysaccharide xyloglucan (see below) <cite>Altmann2008</cite>.  An 1,2-&alpha;-L-fucosidase from ''Bifidobacterium bifidum'' (''Bb''AfcA) cannot hydrolyze the fucosyl linkage when the Gal residue is further modified, i.e. the enzyme does not act on blood group A- and B-trisaccharides (see <cite>Liu2007</cite> for structures). 3-Fucosyllactose, Gal&beta;1-4(Fuc&alpha;1-3)Glc, is slightly hydrolyzed by the ''Bb''AfcA.  1,2-&alpha;-L-Fucosidases from ''Arabidopsis thaliana'' and ''Lilium longiflorum''(lily) can liberate L-fucose from xyloglucan fragment XXFG [Xyl&alpha;1-6Glc&beta;1-4(Xyl&alpha;1-6)Glc&beta;1-4(Fuc&alpha;1-2Gal&beta;1-2Xyl&alpha;1-6)Glc&beta;1-4Glc] as well as 2'-fucosyllactose, but does not liberate L-fucose from 3-fucosyllactose. Both ''Bb''AfcA and the plant enzymes do not act on other linkages and artificial substrates such as 4'-nitrophenyl-&alpha;-L-fucoside.
 == Kinetics and Mechanism ==
-Hydrolysis catalyzed by this family of the enzymes proceeds via an inverting mechanism, as first shown by Katayama et al. <cite>Katayama2004</cite>.
+Hydrolysis catalyzed by this family of the enzymes proceeds via an [[inverting]] mechanism, as first shown by Katayama et al. using <sup>1</sup>H-NMR <cite>Katayama2004</cite>.
 The best characterized member of this family is the 1,2-&alpha;-L-fucosidase from ''Bifidobacterium bifidum'' (''Bb''AfcA). The ''k''<sub>cat</sub> and ''K''<sub>m</sub> values of ''Bb''AfcA for 2'-fucosyllactose, Fuc&alpha;1-2Gal&beta;1-4Glc, were determined to be 0.091 mM and 160 s-1, respectively <cite>Katayama2004</cite>.
 == Catalytic Residues ==
-GH95 enzymes are considered to employ a unique reaction mechanism, in which Asp-activated Asn acts as a base residue while the role of an acid residue is played by a canonical carboxylic residue Glu. In ''Bb''AfcA, Glu566 and Asn423 are identified to be the general acid and base residues, respectively<cite>Nagae2007</cite>. Glu566 is hydrogen-bonded with Asn421, and this hydrogen bond is thought to be important for the side chain of Glu566 to be suitable oriented towards the oxygen atom (O2) of the leaving Gal. Asn423 is activated by the neighboring Asp766, and consequently activates a nucleophilic water molecule. This model (carboxylic acid-mediated activation of amido group) invokes the substrate-assisted catalysis employed by GH18, 20, and 85.
+GH95 enzymes are considered to employ a unique reaction mechanism, in which Asp-activated Asn acts as a general-base catalyst while the role of the general-acid catalyst is played by a canonical carboxylic residue, Glu. In ''Bb''AfcA, Glu566 and Asn423 have been identified as the general-acid and -base residues, respectively<cite>Nagae2007</cite>. Glu566 is hydrogen-bonded with Asn421, and this hydrogen bond is thought to be important in orienting the side chain of Glu566 toward the oxygen atom (O2) of the departing Gal. Asn423 is activated by the neighboring Asp766, and consequently activates a nucleophilic water molecule. This model (carboxylic acid-mediated activation of amido group) bears analogy to the substrate-assisted catalysis mechanism employed by members of [[GH18]], [[GH20]], and [[GH85]].
-The four residues are invariable in the members of this family, and the substitution of alanine or glycine diminished the activities by 1,000- to 10,000-fold<cite>Nagae2007</cite>.
+These four residues are invariable in the members of this family, and substitution with alanine or glycine diminishes activities by 1,000- to 10,000-fold<cite>Nagae2007</cite>.
 == Three-dimensional structures ==
@@ Line 43: / Line 43: @@
 == Family Firsts ==
-;First stereochemistry determination:1,2-&alpha;-L-Fucosidase from ''Bifidobacterium bifidum'', determined by 1H-NMR using 2'-fucosyllactose as a substrate.<cite>Katayama2004</cite>.
+;First stereochemistry determination:1,2-&alpha;-L-Fucosidase from ''Bifidobacterium bifidum'', determined by <sup>1</sup>H-NMR using 2'-fucosyllactose as a substrate.<cite>Katayama2004</cite>.
 ;First molecular cloning:1,2-&alpha;-L-Fucosidase from ''Bifidobacterium bifidum'', by expression cloning using a genomic library conctructed in ''Escherichia coli''<cite>Katayama2004</cite>.
 ;First catalytic base identification:1,2-&alpha;-L-Fucosidase from ''Bifidobacterium bifidum'', kinetic analysis and chemical rescue of the mutants <cite>Nagae2007</cite>.
@@ Line 54: / Line 54: @@
 #Altmann2008 pmid=18495185
 #Nagae2007 pmid=17459873
 </biblio>
 [[Category:Glycoside Hydrolase Families|GH095]]