Carbohydrate Binding Module Family 1 - Revision history

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

2021-12-18T21:14:12Z

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

Harry Brumer: /* Family Firsts */

2018-01-18T17:03:06Z

Family Firsts

Elizabeth Ficko-Blean: /* Family Firsts */

2018-01-18T13:33:59Z

Family Firsts

Harry Brumer: /* Ligand specificities */

2018-01-10T18:13:34Z

Ligand specificities

Harry Gilbert: /* Ligand specificities */

2018-01-10T17:48:27Z

Ligand specificities

Harry Gilbert: /* References */

2018-01-10T17:47:42Z

References

Harry Gilbert: /* Ligand specificities */

2018-01-10T17:44:54Z

Ligand specificities

Elizabeth Ficko-Blean: /* Family Firsts */

2017-11-27T08:20:28Z

Family Firsts

Markus Linder at 03:37, 27 November 2017

2017-11-27T03:37:37Z

Harry Brumer: repositioned figure

2017-11-27T01:17:07Z

repositioned figure

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-* [[Author]]:  ^^^Markus Linder^^^
+* [[Author]]:  [[User:Markus Linder|Markus Linder]]
-* [[Responsible Curator]]:  ^^^Markus Linder^^^
+* [[Responsible Curator]]:  [[User:Markus Linder|Markus Linder]]
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 == Family Firsts ==
-;First Identified
+;First Identified: Family 1 CBMs were found first in studies on the ''Trichoderma reesei'' Cel7A enzyme (then called cellobiohydrolase I, CBHI) using papain for fragmentation. These studies revealed that Cel7A had a “bifunctional” organization with one part binding strongly to cellulose and the other part containing the catalytic machinery <cite>vantilbeurgh1986</cite>. It was noted that sequences homologous to the smaller cellulose binding polypeptide sequence was found in many fungal cellulases and that a synthetic analogue functioned identically to the native fragments produced by proteolysis <cite>Johansson1989</cite>.
-Family 1 CBMs were found first in studies on the ''Trichoderma reesei'' Cel7A enzyme (then called cellobiohydrolase I, CBHI) using papain for fragmentation. These studies revealed that Cel7A had a “bifunctional” organization with one part binding strongly to cellulose and the other part containing the catalytic machinery <cite>vantilbeurgh1986</cite>. It was noted that sequences homologous to the smaller cellulose binding polypeptide sequence was found in many fungal cellulases and that a synthetic analogue functioned identically to the native fragments produced by proteolysis <cite>Johansson1989</cite>.
+;First Structural Characterization: The synthetic version of the ''Trichoderma reesei'' Cel7A cellulose binding domain was analysed by NMR and it was the first CBM1 structure determined <cite>#Kraulis1989</cite>. With the structure determined the research then led to a number of structure-function studies identifying the amino acids responsible for binding <cite>Linder1995</cite> and changing of binding properties by protein engineering <cite>Linder1999</cite>.
 == References ==

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 == Family Firsts ==
-Family 1 CBMs were found first in studies on the ''Trichoderma reesei'' Cel7A enzyme (then called cellobiohydrolase I, CBHI) using papain for fragmentation. These studies revealed that Cel7A had a “bifunctional” organization with one part binding strongly to cellulose and the other part containing the catalytic machinery <cite>vantilbeurgh1986</cite>. It was noted that sequences homologous to the smaller cellulose binding polypeptide sequence was found in many fungal cellulases and that a synthetic analogue functioned identically to the native fragments produces by proteolysis <cite>Johansson1989</cite>. The synthetic version of the cellulose binding domain was then analysed by NMR and its structure was determined <cite>#Kraulis1989</cite>. With the structure determined the research then led to a number of structure-function studies identifying the amino acids responsible for binding <cite>Linder1995</cite> and changing of binding properties by protein engineering <cite>Linder1999</cite>.
 == References ==

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 == Ligand specificities ==
-The family 1 CBMs are found mainly in fungal enzymes <cite>Varnai2014,Martinez2015</cite>. Early work showed that family 1 CBMs bind to cellulose <cite>Johansson1989</cite> and that some, but not all, family 1 CBMs bind to chitin as well <cite>Linder1996</cite>. There is also a contribution of CBMs in binding to lignin, but this binding was shown to be non-specific as it was easily blocked by surfactants <cite>Palonen2004</cite>. The site of binding of a CBM1 to crystalline cellulose was determined by transmission electron microscopy of gold labelled CBM1 fused to modified protein A. The data showed that the CBM1 bound to the 110 face of Valonia cellulose <cite>Lehtio2003</cite>  Based on NMR measurements it was shown that family 1 CBMs could bind to cellohexaose, but not to shorter cellotriose and cellobiose <cite>Mattinen1997</cite>.
+The family 1 CBMs are found mainly in fungal enzymes <cite>Varnai2014,Martinez2015</cite>. Early work showed that family 1 CBMs bind to cellulose <cite>Johansson1989</cite> and that some, but not all, family 1 CBMs bind to chitin as well <cite>Linder1996</cite>. There is also a contribution of CBMs in binding to lignin, but this binding was shown to be non-specific as it was easily blocked by surfactants <cite>Palonen2004</cite>. The site of binding of a CBM1 to crystalline cellulose was determined by transmission electron microscopy of gold labelled CBM1 fused to modified Protein A. The data showed that the CBM1 bound to the 110 face of Valonia cellulose <cite>Lehtio2003</cite>  Based on NMR measurements it was shown that family 1 CBMs could bind to cellohexaose, but not to shorter cellotriose and cellobiose <cite>Mattinen1997</cite>.
 == Structural Features ==

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 == Ligand specificities ==
-The family 1 CBMs are found mainly in fungal enzymes <cite>Varnai2014,Martinez2015</cite>. Early work showed that family 1 CBMs bind to cellulose <cite>Johansson1989</cite> and that some, but not all, family 1 CBMs bind to chitin as well <cite>Linder1996</cite>. There is also a contribution of CBMs in binding to lignin, but this binding was shown to be non-specific as it was easily blocked by surfactants <cite>Palonen2004</cite>. The site of binding of a CBM1 to crystalline cellulose was determined by transmission electron microscopy of gold labelled CBM1 fused to modified protein A. The data showed that the CBM1 bound to the 110 face of Valonia cellulose <cite>Lehtio,2003</cite>  Based on NMR measurements it was shown that family 1 CBMs could bind to cellohexaose, but not to shorter cellotriose and cellobiose <cite>Mattinen1997</cite>.
+The family 1 CBMs are found mainly in fungal enzymes <cite>Varnai2014,Martinez2015</cite>. Early work showed that family 1 CBMs bind to cellulose <cite>Johansson1989</cite> and that some, but not all, family 1 CBMs bind to chitin as well <cite>Linder1996</cite>. There is also a contribution of CBMs in binding to lignin, but this binding was shown to be non-specific as it was easily blocked by surfactants <cite>Palonen2004</cite>. The site of binding of a CBM1 to crystalline cellulose was determined by transmission electron microscopy of gold labelled CBM1 fused to modified protein A. The data showed that the CBM1 bound to the 110 face of Valonia cellulose <cite>Lehtio2003</cite>  Based on NMR measurements it was shown that family 1 CBMs could bind to cellohexaose, but not to shorter cellotriose and cellobiose <cite>Mattinen1997</cite>.
 == Structural Features ==

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 #Linder1996 pmid=8702902
 #Palonen2004 pmid=14687972
 #Mattinen1997 pmid=9175871
 #Kraulis1989 pmid=2554967

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 The family 1 CBMs are found mainly in fungal enzymes <cite>Varnai2014,Martinez2015</cite>. Early work showed that family 1 CBMs bind to cellulose <cite>Johansson1989</cite> and that some, but not all, family 1 CBMs bind to chitin as well <cite>Linder1996</cite>. There is also a contribution of CBMs in binding to lignin, but this binding was shown to be non-specific as it was easily blocked by surfactants <cite>Palonen2004</cite>. Based on NMR measurements it was shown that family 1 CBMs could bind to cellohexaose, but not to shorter cellotriose and cellobiose <cite>Mattinen1997</cite>.
 [[File:CBM 1.png|thumb|300px|right|'''Figure 1.''' ''Top.'' A backbone trace of the ''T.reesei'' Cel7A CBM showing residues that have been identified as important for the interaction with cellulose. ''Below.'' The structure flipped 90 degrees to show how the aromatic residues align with pyronose rings in a cellulose molecule.]]
 Structurally the family 1 CBMs are distinct from other families. They are relatively small, only about 35 amino acids and have two or three disulphide bridges that stabilize their fold <cite>Kraulis1989</cite>. This type of fold is called a cystine knot and is also found in a family of toxins, called conotoxins produced by cone shells <cite>Norton1989</cite>. This structure is rigid and on the CBM there are three aromatic residues (tyrosines or tryptophans) that align so that their spacing is the same as every second pyranose ring on cellulose. Together with some hydrogen bond forming side chains this triad of aromatic residues form a binding face that docks onto the cellulose surface. It has also been shown using synthesised peptides that carbohydrates added to the CBMs affect their binding properties <cite>Happs2015</cite>.