in a psychrophilic cellulase from the Antarctic bacterium
The cold-adapted cellulase CelG has been purified from the culture supernatant of the Antarctic bacterium Pseudoalteromonas haloplanktis and the gene coding for this enzyme has been cloned, sequenced and expressed in Escherichia coli. This cellulase is composed of three structurally and functionally...
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ftciteseerx:oai:CiteSeerX.psu:10.1.1.320.293 2023-05-15T13:34:03+02:00 in a psychrophilic cellulase from the Antarctic bacterium Geneviève Garsoux Josette Lamotte Charles Gerday Georges Feller The Pennsylvania State University CiteSeerX Archives application/pdf http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.320.293 http://www2.ulg.ac.be/biochlab/pdf/pub/BiochemJ_2004.pdf en eng http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.320.293 http://www2.ulg.ac.be/biochlab/pdf/pub/BiochemJ_2004.pdf Metadata may be used without restrictions as long as the oai identifier remains attached to it. http://www2.ulg.ac.be/biochlab/pdf/pub/BiochemJ_2004.pdf Key words carbohydrate-binding module cellulase extremophile glycoside hydrolase Pseudoalteromonas haloplanktis text ftciteseerx 2016-09-04T00:18:17Z The cold-adapted cellulase CelG has been purified from the culture supernatant of the Antarctic bacterium Pseudoalteromonas haloplanktis and the gene coding for this enzyme has been cloned, sequenced and expressed in Escherichia coli. This cellulase is composed of three structurally and functionally distinct regions: an N-terminal catalytic domain belonging to glycosidase family 5 and a C-terminal cellulose-binding domain belonging to carbohydrate-binding module family 5. The linker of 107 residues connecting both domains is one of the longest found in cellulases, and optimizes substrate accessibility to the catalytic domain by drastically increasing the surface of cellulose available to a bound enzyme molecule. The psychrophilic enzyme is closely related to the cellulase Cel5 from Erwinia chrysanthemi. Both k cat and k cat/K m values at 4 ◦ C for the psychrophilic cellulase are similar to the values for Cel5 at 30–35 ◦ C, suggesting temperature adaptation of the kinetic parameters. The thermodynamic parameters of activation of CelG suggest a heat-labile, relatively disordered active site with low substrate affinity, in agreement with the experimental data. The structure of CelG has been constructed by homology modelling with a molecule of cellotetraose docked into the active site. No structural alteration related to cold-activity can be found in the catalytic cleft, whereas several structural factors in the overall structure can explain the weak thermal stability, suggesting that the loss of stability provides the required active-site mobility at low temperatures. Text Antarc* Antarctic Unknown Antarctic The Antarctic |
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English |
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Key words carbohydrate-binding module cellulase extremophile glycoside hydrolase Pseudoalteromonas haloplanktis |
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Key words carbohydrate-binding module cellulase extremophile glycoside hydrolase Pseudoalteromonas haloplanktis Geneviève Garsoux Josette Lamotte Charles Gerday Georges Feller in a psychrophilic cellulase from the Antarctic bacterium |
topic_facet |
Key words carbohydrate-binding module cellulase extremophile glycoside hydrolase Pseudoalteromonas haloplanktis |
description |
The cold-adapted cellulase CelG has been purified from the culture supernatant of the Antarctic bacterium Pseudoalteromonas haloplanktis and the gene coding for this enzyme has been cloned, sequenced and expressed in Escherichia coli. This cellulase is composed of three structurally and functionally distinct regions: an N-terminal catalytic domain belonging to glycosidase family 5 and a C-terminal cellulose-binding domain belonging to carbohydrate-binding module family 5. The linker of 107 residues connecting both domains is one of the longest found in cellulases, and optimizes substrate accessibility to the catalytic domain by drastically increasing the surface of cellulose available to a bound enzyme molecule. The psychrophilic enzyme is closely related to the cellulase Cel5 from Erwinia chrysanthemi. Both k cat and k cat/K m values at 4 ◦ C for the psychrophilic cellulase are similar to the values for Cel5 at 30–35 ◦ C, suggesting temperature adaptation of the kinetic parameters. The thermodynamic parameters of activation of CelG suggest a heat-labile, relatively disordered active site with low substrate affinity, in agreement with the experimental data. The structure of CelG has been constructed by homology modelling with a molecule of cellotetraose docked into the active site. No structural alteration related to cold-activity can be found in the catalytic cleft, whereas several structural factors in the overall structure can explain the weak thermal stability, suggesting that the loss of stability provides the required active-site mobility at low temperatures. |
author2 |
The Pennsylvania State University CiteSeerX Archives |
format |
Text |
author |
Geneviève Garsoux Josette Lamotte Charles Gerday Georges Feller |
author_facet |
Geneviève Garsoux Josette Lamotte Charles Gerday Georges Feller |
author_sort |
Geneviève Garsoux |
title |
in a psychrophilic cellulase from the Antarctic bacterium |
title_short |
in a psychrophilic cellulase from the Antarctic bacterium |
title_full |
in a psychrophilic cellulase from the Antarctic bacterium |
title_fullStr |
in a psychrophilic cellulase from the Antarctic bacterium |
title_full_unstemmed |
in a psychrophilic cellulase from the Antarctic bacterium |
title_sort |
in a psychrophilic cellulase from the antarctic bacterium |
url |
http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.320.293 http://www2.ulg.ac.be/biochlab/pdf/pub/BiochemJ_2004.pdf |
geographic |
Antarctic The Antarctic |
geographic_facet |
Antarctic The Antarctic |
genre |
Antarc* Antarctic |
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Antarc* Antarctic |
op_source |
http://www2.ulg.ac.be/biochlab/pdf/pub/BiochemJ_2004.pdf |
op_relation |
http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.320.293 http://www2.ulg.ac.be/biochlab/pdf/pub/BiochemJ_2004.pdf |
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Metadata may be used without restrictions as long as the oai identifier remains attached to it. |
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