https://www.cazypedia.org/index.php?title=Glycoside_Hydrolase_Family_1&feed=atom&action=history
Glycoside Hydrolase Family 1 - Revision history
2024-03-28T19:54:50Z
Revision history for this page on the wiki
MediaWiki 1.35.10
https://www.cazypedia.org/index.php?title=Glycoside_Hydrolase_Family_1&diff=7911&oldid=prev
Spencer Williams at 01:10, 28 November 2012
2012-11-28T01:10:20Z
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<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>== Catalytic Residues ==</div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>== Catalytic Residues ==</div></td></tr>
<tr><td class='diff-marker'>−</td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div>The [[catalytic nucleophile]] was first identified in the ''Agrobacterium'' sp. β-glucosidase as Glu358 in the sequence YIT'''<u>E</u>'''NG through trapping of the 2-deoxy-2-fluoroglucosyl-enzyme [[intermediate]] and subsequent peptide mapping <cite>8</cite>. The [[general acid/base]] catalyst was first identified as Glu170 in this same enzyme through detailed mechanistic analysis of mutants at that position, which included azide rescue experiments <cite>9</cite>. Family GH1 enzymes, as is typical of [http://www.cazy.org/fam/acc_GH.html#table Clan GH-A], have an asparagine residue preceding the [[general acid/base]] catalyst in a typical NEP sequence. The asparagine engages in important hydrogen bonding interactions with the substrate 2-hydroxyl. Interestingly, the plant myrosinases cleave thioglycosides bearing an anionic aglycone (glucosinolates), and have evolved an active site in which the acid/base glutamate is replaced by glutamine. Substrates are sufficiently reactive not to require the acid catalyst, while the role of base catalyst is played by exogenous ascorbate, which binds to the glycosyl enzyme <cite>13</cite>.</div></td><td class='diff-marker'>+</td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div>The [[catalytic nucleophile]] was first identified in the ''Agrobacterium'' sp. β-glucosidase as Glu358 in the sequence YIT'''<u>E</u>'''NG through trapping of the 2-deoxy-2-fluoroglucosyl-enzyme [[intermediate]] and subsequent peptide mapping <cite>8</cite>. The [[general acid/base]] catalyst was first identified as Glu170 in this same enzyme through detailed mechanistic analysis of mutants at that position, which included azide rescue experiments <cite>9</cite>. Family GH1 enzymes, as is typical of [http://www.cazy.org/fam/acc_GH.html#table Clan GH-A], have an asparagine residue preceding the [[general acid/base]] catalyst in a typical NEP sequence. The asparagine engages in important hydrogen bonding interactions with the substrate 2-hydroxyl. Interestingly, the plant myrosinases cleave thioglycosides bearing an anionic aglycone (glucosinolates), and have evolved an active site in which the acid/base glutamate is replaced by glutamine. Substrates are sufficiently reactive not to require the acid catalyst, while the role of base catalyst is played by exogenous ascorbate, which binds to the glycosyl enzyme <cite>13</cite><ins class="diffchange diffchange-inline">. For a related example see the mannose-1-phosphate-6-mannoside cleaving α-mannosidases of family [[GH92]], which also lack an enzymic [[general acid]] residue</ins>.</div></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>== Three-dimensional structures ==</div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>== Three-dimensional structures ==</div></td></tr>
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Spencer Williams
https://www.cazypedia.org/index.php?title=Glycoside_Hydrolase_Family_1&diff=7498&oldid=prev
Harry Brumer: updated CAZyDBlink
2012-09-10T16:30:29Z
<p>updated CAZyDBlink</p>
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Harry Brumer
https://www.cazypedia.org/index.php?title=Glycoside_Hydrolase_Family_1&diff=6994&oldid=prev
Spencer Williams at 23:03, 22 November 2011
2011-11-22T23:03:01Z
<p></p>
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<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>== Three-dimensional structures ==</div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>== Three-dimensional structures ==</div></td></tr>
<tr><td class='diff-marker'>−</td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div>Three-dimensional structures are available for a large number of Family 1 enzymes, the first solved being that of the white clover (''Trifolium repens'') cyanogenic β-glucosidase <cite>12</cite>. As members of Clan GH-A they have a classical (&alpha;/&beta;)<sub>8</sub> TIM barrel fold with the two key active site glutamic acids being approximately 200 residues apart in sequence and located at the C-terminal ends of β-strands 4 (acid/base) and 7 (nucleophile) <cite>10</cite>.</div></td><td class='diff-marker'>+</td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div>Three-dimensional structures are available for a large number of Family 1 enzymes, the first solved being that of the white clover (''Trifolium repens'') cyanogenic β-glucosidase <cite>12</cite>. As members of <ins class="diffchange diffchange-inline">[[</ins>Clan<ins class="diffchange diffchange-inline">]] </ins>GH-A they have a classical (&alpha;/&beta;)<sub>8</sub> TIM barrel fold with the two key active site glutamic acids being approximately 200 residues apart in sequence and located at the C-terminal ends of β-strands 4 (acid/base) and 7 (nucleophile) <cite>10</cite>.</div></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>== "Family Firsts" ==</div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>== "Family Firsts" ==</div></td></tr>
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Spencer Williams
https://www.cazypedia.org/index.php?title=Glycoside_Hydrolase_Family_1&diff=6993&oldid=prev
Spencer Williams at 22:01, 22 November 2011
2011-11-22T22:01:26Z
<p></p>
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<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>;First sterochemistry determination: ''Agrobacterium'' sp. (formerly ''Alcaligenes faecalis'') β-glucosidase by NMR <cite>2</cite></div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>;First sterochemistry determination: ''Agrobacterium'' sp. (formerly ''Alcaligenes faecalis'') β-glucosidase by NMR <cite>2</cite></div></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>;First [[catalytic nucleophile]] identification: ''Agrobacterium'' sp. (formerly ''Alcaligenes faecalis'') β-glucosidase by 2-fluoroglucose labeling <cite>8</cite></div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>;First [[catalytic nucleophile]] identification: ''Agrobacterium'' sp. (formerly ''Alcaligenes faecalis'') β-glucosidase by 2-fluoroglucose labeling <cite>8</cite></div></td></tr>
<tr><td class='diff-marker'>−</td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div>;First [[general acid/base]] residue identification: ''Agrobacterium'' sp. (formerly ''Alcaligenes faecalis'') β-glucosidase by rescue kinetics with mutants <del class="diffchange diffchange-inline">(</del><cite>9</cite></div></td><td class='diff-marker'>+</td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div>;First [[general acid/base]] residue identification: ''Agrobacterium'' sp. (formerly ''Alcaligenes faecalis'') β-glucosidase by rescue kinetics with mutants <cite>9</cite></div></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>;First 3-D structure of a GH1 enzyme: White clover (''Trifolium repens'') cyanogenic β-glucosidase <cite>12</cite></div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>;First 3-D structure of a GH1 enzyme: White clover (''Trifolium repens'') cyanogenic β-glucosidase <cite>12</cite></div></td></tr>
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Spencer Williams
https://www.cazypedia.org/index.php?title=Glycoside_Hydrolase_Family_1&diff=6992&oldid=prev
Spencer Williams at 21:52, 22 November 2011
2011-11-22T21:52:15Z
<p></p>
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<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>== Substrate specificities ==</div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>== Substrate specificities ==</div></td></tr>
<tr><td class='diff-marker'>−</td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div>The most common known enzymatic activities for [[glycoside hydrolases]] in this family<del class="diffchange diffchange-inline">, at the current time, </del>are β-glucosidases and β-galactosidases: indeed typically both activities are found within the same active site, often with similar ''k''<sub>cat</sub> values, but with substantially higher ''K''<sub>m</sub> values for the galactosides. However, other commonly found activities are 6-phospho-β-glucosidase and 6-phospho-β-galactosidase, β-mannosidase, β-D-fucosidase and β-glucuronidase. Family GH1 enzymes are found across a broad spectrum of life forms. Enzymes of medical interest include the human lactase/phlorizin hydrolase whose deficiency leads to lactose intolerance. In plants Family GH1 enzymes are often involved in the processing of glycosylated aromatics such as saponins and some plant hormones stored in inactive glycosylated forms. Indeed some have been identified as plant oncogenes due to aberrant control of auxin levels. Some plants also use Family GH1 enzymes as part of their defense system in order to release toxic aglycons, the most known examples being ''Trifolium repens'' β-glucosidase and ''Sinapis alba'' myrosinase, which respectively hydrolyse linamarin and glucosinolates. One of the work horses of glycosidase enzymology, the almond emulsin β-glucosidase, even though not fully sequenced, is deduced to belong to Family GH1 by limited sequence analysis <cite>1</cite>.</div></td><td class='diff-marker'>+</td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div>The most common known enzymatic activities for [[glycoside hydrolases]] in this family are β-glucosidases and β-galactosidases: indeed typically both activities are found within the same active site, often with similar ''k''<sub>cat</sub> values, but with substantially higher ''K''<sub>m</sub> values for the galactosides. However, other commonly found activities are 6-phospho-β-glucosidase and 6-phospho-β-galactosidase, β-mannosidase, β-D-fucosidase and β-glucuronidase. Family GH1 enzymes are found across a broad spectrum of life forms. Enzymes of medical interest include the human lactase/phlorizin hydrolase whose deficiency leads to lactose intolerance. In plants Family GH1 enzymes are often involved in the processing of glycosylated aromatics such as saponins and some plant hormones stored in inactive glycosylated forms. Indeed some have been identified as plant oncogenes due to aberrant control of auxin levels. Some plants also use Family GH1 enzymes as part of their defense system in order to release toxic aglycons, the most known examples being ''Trifolium repens'' β-glucosidase and ''Sinapis alba'' myrosinase, which respectively hydrolyse linamarin and glucosinolates. One of the work horses of glycosidase enzymology, the almond emulsin β-glucosidase, even though not fully sequenced, is deduced to belong to Family GH1 by limited sequence analysis <cite>1</cite>.</div></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>== Kinetics and Mechanism ==</div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>== Kinetics and Mechanism ==</div></td></tr>
</table>
Spencer Williams
https://www.cazypedia.org/index.php?title=Glycoside_Hydrolase_Family_1&diff=2855&oldid=prev
Harry Brumer at 13:51, 8 November 2009
2009-11-08T13:51:56Z
<p></p>
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<td colspan="2" style="background-color: #fff; color: #202122; text-align: center;">Revision as of 13:51, 8 November 2009</td>
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<tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins style="font-weight: bold; text-decoration: none;">{{CuratorApproved}}</ins></div></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>* [[Author]]: [[User:Withers|Stephen Withers]]</div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>* [[Author]]: [[User:Withers|Stephen Withers]]</div></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>* [[Responsible Curator]]: [[User:Withers|Stephen Withers]]</div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>* [[Responsible Curator]]: [[User:Withers|Stephen Withers]]</div></td></tr>
</table>
Harry Brumer
https://www.cazypedia.org/index.php?title=Glycoside_Hydrolase_Family_1&diff=1835&oldid=prev
Spencer Williams: /* "Family Firsts" */
2009-09-01T02:06:40Z
<p><span dir="auto"><span class="autocomment">"Family Firsts"</span></span></p>
<table class="diff diff-contentalign-left diff-editfont-monospace" data-mw="interface">
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<td colspan="2" style="background-color: #fff; color: #202122; text-align: center;">Revision as of 02:06, 1 September 2009</td>
</tr><tr><td colspan="2" class="diff-lineno" id="mw-diff-left-l38" >Line 38:</td>
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<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>== "Family Firsts" ==</div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>== "Family Firsts" ==</div></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>;First sterochemistry determination: ''Agrobacterium'' sp. (formerly ''Alcaligenes faecalis'') β-glucosidase by NMR <cite>2</cite></div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>;First sterochemistry determination: ''Agrobacterium'' sp. (formerly ''Alcaligenes faecalis'') β-glucosidase by NMR <cite>2</cite></div></td></tr>
<tr><td class='diff-marker'>−</td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div>;First catalytic nucleophile identification: ''Agrobacterium'' sp. (formerly ''Alcaligenes faecalis'') β-glucosidase by 2-fluoroglucose labeling <cite>8</cite></div></td><td class='diff-marker'>+</td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div>;First <ins class="diffchange diffchange-inline">[[</ins>catalytic nucleophile<ins class="diffchange diffchange-inline">]] </ins>identification: ''Agrobacterium'' sp. (formerly ''Alcaligenes faecalis'') β-glucosidase by 2-fluoroglucose labeling <cite>8</cite></div></td></tr>
<tr><td class='diff-marker'>−</td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div>;First general acid/base residue identification: ''Agrobacterium'' sp. (formerly ''Alcaligenes faecalis'') β-glucosidase by rescue kinetics with mutants (<cite>9</cite></div></td><td class='diff-marker'>+</td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div>;First <ins class="diffchange diffchange-inline">[[</ins>general acid/base<ins class="diffchange diffchange-inline">]] </ins>residue identification: ''Agrobacterium'' sp. (formerly ''Alcaligenes faecalis'') β-glucosidase by rescue kinetics with mutants (<cite>9</cite></div></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>;First 3-D structure of a GH1 enzyme: White clover (''Trifolium repens'') cyanogenic β-glucosidase <cite>12</cite></div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>;First 3-D structure of a GH1 enzyme: White clover (''Trifolium repens'') cyanogenic β-glucosidase <cite>12</cite></div></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td></tr>
</table>
Spencer Williams
https://www.cazypedia.org/index.php?title=Glycoside_Hydrolase_Family_1&diff=1832&oldid=prev
Spencer Williams at 02:04, 1 September 2009
2009-09-01T02:04:10Z
<p></p>
<table class="diff diff-contentalign-left diff-editfont-monospace" data-mw="interface">
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<td colspan="2" style="background-color: #fff; color: #202122; text-align: center;">Revision as of 02:04, 1 September 2009</td>
</tr><tr><td colspan="2" class="diff-lineno" id="mw-diff-left-l25" >Line 25:</td>
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<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>== Substrate specificities ==</div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>== Substrate specificities ==</div></td></tr>
<tr><td class='diff-marker'>−</td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div>The most common known enzymatic activities for [[glycoside hydrolases]] in this family, at the current time, are <del class="diffchange diffchange-inline">those of </del>β-glucosidases and β-galactosidases: indeed typically both activities are found within the same active site, often with similar ''k''<sub>cat</sub> values, but with substantially higher ''K''<sub>m</sub> values for the galactosides. However, other commonly found activities are 6-phospho-β-glucosidase and 6-phospho-β-galactosidase, β-mannosidase, β-D-fucosidase and β-glucuronidase. Family GH1 enzymes are found across a broad spectrum of life forms. Enzymes of medical interest include the human lactase/phlorizin hydrolase whose deficiency leads to lactose intolerance. In plants Family GH1 enzymes are often involved in the processing of glycosylated aromatics such as saponins and some plant hormones stored in inactive glycosylated forms. Indeed some have been identified as plant oncogenes due to aberrant control of auxin levels. Some plants also use Family GH1 enzymes as part of their defense system in order to release toxic aglycons, the most known examples being ''Trifolium repens'' β-glucosidase and ''Sinapis alba'' myrosinase, which respectively hydrolyse linamarin and glucosinolates. One of the work horses of glycosidase enzymology, the almond emulsin β-glucosidase, even though not fully sequenced, is deduced to belong to Family GH1 by limited sequence analysis <cite>1</cite>.</div></td><td class='diff-marker'>+</td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div>The most common known enzymatic activities for [[glycoside hydrolases]] in this family, at the current time, are β-glucosidases and β-galactosidases: indeed typically both activities are found within the same active site, often with similar ''k''<sub>cat</sub> values, but with substantially higher ''K''<sub>m</sub> values for the galactosides. However, other commonly found activities are 6-phospho-β-glucosidase and 6-phospho-β-galactosidase, β-mannosidase, β-D-fucosidase and β-glucuronidase. Family GH1 enzymes are found across a broad spectrum of life forms. Enzymes of medical interest include the human lactase/phlorizin hydrolase whose deficiency leads to lactose intolerance. In plants Family GH1 enzymes are often involved in the processing of glycosylated aromatics such as saponins and some plant hormones stored in inactive glycosylated forms. Indeed some have been identified as plant oncogenes due to aberrant control of auxin levels. Some plants also use Family GH1 enzymes as part of their defense system in order to release toxic aglycons, the most known examples being ''Trifolium repens'' β-glucosidase and ''Sinapis alba'' myrosinase, which respectively hydrolyse linamarin and glucosinolates. One of the work horses of glycosidase enzymology, the almond emulsin β-glucosidase, even though not fully sequenced, is deduced to belong to Family GH1 by limited sequence analysis <cite>1</cite>.</div></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>== Kinetics and Mechanism ==</div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>== Kinetics and Mechanism ==</div></td></tr>
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<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>== Catalytic Residues ==</div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>== Catalytic Residues ==</div></td></tr>
<tr><td class='diff-marker'>−</td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div>The catalytic nucleophile was first identified in the ''Agrobacterium'' sp. β-glucosidase as Glu358 in the sequence YIT'''<u>E</u>'''NG through trapping of the 2-deoxy-2-fluoroglucosyl-enzyme [[intermediate]] and subsequent peptide mapping <cite>8</cite>. The acid/base catalyst was first identified as Glu170 in this same enzyme through detailed mechanistic analysis of mutants at that position, which included azide rescue experiments <cite>9</cite>. Family GH1 enzymes, as is typical of [http://www.cazy.org/fam/acc_GH.html#table Clan GH-A], have an asparagine residue preceding the acid/base catalyst in a typical NEP sequence. The asparagine engages in important hydrogen bonding interactions with the substrate 2-hydroxyl. Interestingly, the plant myrosinases cleave thioglycosides bearing an anionic aglycone (glucosinolates), and have evolved an active site in which the acid/base glutamate is replaced by glutamine. Substrates are sufficiently reactive not to require the acid catalyst, while the role of base catalyst is played by exogenous ascorbate, which binds to the glycosyl enzyme <cite>13</cite>.</div></td><td class='diff-marker'>+</td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div>The <ins class="diffchange diffchange-inline">[[</ins>catalytic nucleophile<ins class="diffchange diffchange-inline">]] </ins>was first identified in the ''Agrobacterium'' sp. β-glucosidase as Glu358 in the sequence YIT'''<u>E</u>'''NG through trapping of the 2-deoxy-2-fluoroglucosyl-enzyme [[intermediate]] and subsequent peptide mapping <cite>8</cite>. The <ins class="diffchange diffchange-inline">[[general </ins>acid/base<ins class="diffchange diffchange-inline">]] </ins>catalyst was first identified as Glu170 in this same enzyme through detailed mechanistic analysis of mutants at that position, which included azide rescue experiments <cite>9</cite>. Family GH1 enzymes, as is typical of [http://www.cazy.org/fam/acc_GH.html#table Clan GH-A], have an asparagine residue preceding the <ins class="diffchange diffchange-inline">[[general </ins>acid/base<ins class="diffchange diffchange-inline">]] </ins>catalyst in a typical NEP sequence. The asparagine engages in important hydrogen bonding interactions with the substrate 2-hydroxyl. Interestingly, the plant myrosinases cleave thioglycosides bearing an anionic aglycone (glucosinolates), and have evolved an active site in which the acid/base glutamate is replaced by glutamine. Substrates are sufficiently reactive not to require the acid catalyst, while the role of base catalyst is played by exogenous ascorbate, which binds to the glycosyl enzyme <cite>13</cite>.</div></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>== Three-dimensional structures ==</div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>== Three-dimensional structures ==</div></td></tr>
</table>
Spencer Williams
https://www.cazypedia.org/index.php?title=Glycoside_Hydrolase_Family_1&diff=1777&oldid=prev
Spencer Williams at 08:27, 30 August 2009
2009-08-30T08:27:08Z
<p></p>
<table class="diff diff-contentalign-left diff-editfont-monospace" data-mw="interface">
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<td colspan="2" style="background-color: #fff; color: #202122; text-align: center;">Revision as of 08:27, 30 August 2009</td>
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<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>== Kinetics and Mechanism ==</div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>== Kinetics and Mechanism ==</div></td></tr>
<tr><td class='diff-marker'>−</td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div>Family GH1 β-glycosidases are [[retaining]] enzymes, as first shown by NMR <cite>2</cite> and follow a <del class="diffchange diffchange-inline">classical </del>[[Koshland double-displacement mechanism]]. Enzymes that have been well-studied kinetically include the almond emulsin enzyme, for which a particularly nice and important set of studies on rate-limiting steps and inhibition was reported in the mid 1980’s <cite>3 4</cite> and the ''Agrobacterium'' sp. β-glucosidase which has been the subject of a series of kinetic evaluations, including detailed steady state <cite>5 6</cite> and pre-steady state kinetic analyses in which the roles of each substrate hydroxyl in catalysis have also been carefully probed <cite>7</cite>.</div></td><td class='diff-marker'>+</td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div>Family GH1 β-glycosidases are [[retaining]] enzymes, as first shown by NMR <cite>2</cite> and follow a [[<ins class="diffchange diffchange-inline">classical </ins>Koshland double-displacement mechanism]]. Enzymes that have been well-studied kinetically include the almond emulsin enzyme, for which a particularly nice and important set of studies on rate-limiting steps and inhibition was reported in the mid 1980’s <cite>3 4</cite> and the ''Agrobacterium'' sp. β-glucosidase which has been the subject of a series of kinetic evaluations, including detailed steady state <cite>5 6</cite> and pre-steady state kinetic analyses in which the roles of each substrate hydroxyl in catalysis have also been carefully probed <cite>7</cite>.</div></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>== Catalytic Residues ==</div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>== Catalytic Residues ==</div></td></tr>
</table>
Spencer Williams
https://www.cazypedia.org/index.php?title=Glycoside_Hydrolase_Family_1&diff=1763&oldid=prev
Spencer Williams at 02:22, 27 August 2009
2009-08-27T02:22:45Z
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<td colspan="2" style="background-color: #fff; color: #202122; text-align: center;">Revision as of 02:22, 27 August 2009</td>
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<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>== Catalytic Residues ==</div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>== Catalytic Residues ==</div></td></tr>
<tr><td class='diff-marker'>−</td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div>The catalytic nucleophile was first identified in the ''Agrobacterium'' sp. β-glucosidase as Glu358 in the sequence YIT'''<u>E</u>'''NG through trapping of the 2-deoxy-2-fluoroglucosyl-enzyme intermediate and subsequent peptide mapping <cite>8</cite>. The acid/base catalyst was first identified as Glu170 in this same enzyme through detailed mechanistic analysis of mutants at that position, which included azide rescue experiments <cite>9</cite>. Family GH1 enzymes, as is typical of [http://www.cazy.org/fam/acc_GH.html#table Clan GH-A], have an asparagine residue preceding the acid/base catalyst in a typical NEP sequence. The asparagine engages in important hydrogen bonding interactions with the substrate 2-hydroxyl. Interestingly, the plant myrosinases cleave thioglycosides bearing an anionic aglycone (glucosinolates), and have evolved an active site in which the acid/base glutamate is replaced by glutamine. Substrates are sufficiently reactive not to require the acid catalyst, while the role of base catalyst is played by exogenous ascorbate, which binds to the glycosyl enzyme <cite>13</cite>.</div></td><td class='diff-marker'>+</td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div>The catalytic nucleophile was first identified in the ''Agrobacterium'' sp. β-glucosidase as Glu358 in the sequence YIT'''<u>E</u>'''NG through trapping of the 2-deoxy-2-fluoroglucosyl-enzyme <ins class="diffchange diffchange-inline">[[</ins>intermediate<ins class="diffchange diffchange-inline">]] </ins>and subsequent peptide mapping <cite>8</cite>. The acid/base catalyst was first identified as Glu170 in this same enzyme through detailed mechanistic analysis of mutants at that position, which included azide rescue experiments <cite>9</cite>. Family GH1 enzymes, as is typical of [http://www.cazy.org/fam/acc_GH.html#table Clan GH-A], have an asparagine residue preceding the acid/base catalyst in a typical NEP sequence. The asparagine engages in important hydrogen bonding interactions with the substrate 2-hydroxyl. Interestingly, the plant myrosinases cleave thioglycosides bearing an anionic aglycone (glucosinolates), and have evolved an active site in which the acid/base glutamate is replaced by glutamine. Substrates are sufficiently reactive not to require the acid catalyst, while the role of base catalyst is played by exogenous ascorbate, which binds to the glycosyl enzyme <cite>13</cite>.</div></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>== Three-dimensional structures ==</div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>== Three-dimensional structures ==</div></td></tr>
</table>
Spencer Williams